Conservation Practices on Cultivated Cropland - A Comparison of CEAP I and CEAP II Survey Data and Modeling

Conservation
Effects
Assessment
Project
March 2022

Conservation Practices on
Cultivated Cropland
A Comparison of CEAP I and CEAP II
Survey Data and Modeling

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Cover Photo: Lynn Betts, NRCS. Conservation tillage system that leaves at least 30 percent of the soil
covered after planting with last year's crop residue. North-central Iowa. Residue adequately controls
erosion by both wind and water on this soil type. Photo ID NRCS IA99102

CEAP National Report:
Conservation Practices on Cultivated
Cropland
EXECUTIVE SUMMARY
The U.S. Department of Agriculture’s (USDA) Natural Resources Conservation Service (NRCS)
evaluates conservation trends and effects on cultivated cropland through the multiagency
Conservation Effects Assessment Project (CEAP), a sampling and modeling approach using
natural resource data and farmer surveys. The first set of farmer surveys was conducted in 2003–
06 (CEAP I) with reports released from 2010 through 2014. Now, comparison data from farmer
surveys conducted in 2013–16 (CEAP II) make it possible to estimate conservation adoption and
effects between the CEAP survey periods.
The agricultural landscape is dynamic, shaped by policy, technology, and natural resource
drivers among others, which together affect farmer decisions and conservation trends. Between
the CEAP surveys, increased demand and higher prices for commodities encouraged production
expansion in nearly all regions of the country. A warming climate, longer growing season, and
advances in seed technology and higher yielding crop varieties drove cropping pattern shifts,
most notably in the northern and southern plains, where corn and soybean production replaced
wheat and other close-grown crops with lower average nutrient needs, and fallow periods.
The agricultural landscape continued to shift between the two survey periods. Demand for
commodities increased, particularly corn and soybeans, and higher prices encouraged production
expansion. A warming climate, longer growing season, and seed technology advances extended
the northern boundaries of corn and soybean production, where they replaced crops such as
wheat and other close-grown crops with significantly lower average nutrient needs and fallow
periods.
During the decade:
● Farmers increasingly adopted advanced technology, including enhanced-efficiency fertilizers and
variable-rate fertilization to improve efficiency and benefit rural economies and the environment.

● More efficient conservation tillage systems, particularly no-till, became the dominant form of
tillage, reducing erosion and fuel use.

● Use of structural practices increased, largely in combination with conservation tillage as farmers

integrated multiple conservation treatments to gain efficiencies.
Conservation crop rotation and cover crop use increased, as did the use of high-biomass crops in
rotation.
● Irrigators shifted toward more efficient pressure-based systems, and improved water management
strategies decreased per-acre water application rates.
●

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Conservation Effects Assessment Project

As a result, CEAP estimates:
● Average annual water (sheet and rill) and wind erosion dropped by 70 million and 94 million
tons, respectively, and edge-of-field sediment loss declined by 74 million tons.

● Nearly 26 million additional acres of cultivated cropland were gaining soil carbon, and by CEAP

II carbon gains on all cultivated cropland increased by over 8.8 million tons per year.
Nitrogen and phosphorus losses through surface pathways declined by 3 and 6 percent,
respectively. However, subsurface nitrogen and soluble phosphorus losses increased by 13 and 11
percent, respectively.
● Per-acre irrigation application rates dropped by 19 percent and national withdrawals by 7 millionacre-feet.
● Average annual fuel use dropped by 110 million gallons of diesel fuel equivalents, avoiding
associated greenhouse gas emissions of nearly 1.2 million tons of carbon dioxide equivalents.
●

While gains were made, shifts in crops, cropping patterns, and tillage systems outpaced nutrient
application research and guidance and industry capacity to deliver and apply nutrients efficiently.
Consequently, subsurface losses of nitrogen and soluble phosphorus increased with the
expansion of crops with higher nutrient demand and conservation tillage systems, which promote
water infiltration and subsurface flow. Transitioning to conservation tillage systems, particularly
no-till, requires nutrient method and form adjustments to incorporate nutrients that previously
may have been tilled into the soil under conventional systems.
Recognizing the variability in conservation treatment needs within fields and addressing soil
health and nutrient management as a system is critical to achieving the full benefits of advanced
technology, tillage efficiency, and conservation measures. For example, in each CEAP survey
period, a small proportion of acres accounted for most nutrient and sediment losses; in CEAP II,
73 percent of the subsurface nitrogen losses came from 28 percent of the acres, generally
smaller, vulnerable areas within larger fields.
A systems approach to conservation recognizes in-field variability and the connectivity of natural
resources, and that conservation measures designed to benefit one resource also may affect
another, potentially negatively. For example, in a watershed in which soluble phosphorus is a
resource concern, nutrient incorporation may be needed to reduce potential soluble losses, but it
also may reduce the maximum soil carbon benefits of strict no-till. Conservation planning
assesses the agri-environmental system to identify and develop workable solutions that fit the
operation, the land, and the resource need in balance with local natural resource priorities.

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TABLE OF CONTENTS
EXECUTIVE SUMMARY .......................................................................................................................................... i
INTRODUCTION.................................................................................................................................................... 1
CEAP Production Regions .................................................................................................................................................. 1
A Changing Agricultural Landscape ................................................................................................................................... 5
Farms and Ownership .................................................................................................................................................. 5
Cropping Patterns......................................................................................................................................................... 6
Prevailing Weather....................................................................................................................................................... 6
Production Technology ................................................................................................................................................ 7

HOW DID THE USE OF CONSERVATION PRACTICES CHANGE BETWEEN THE CEAP SURVEYS? .............................. 10
Structural Practices and Conservation Tillage ................................................................................................................. 10
Structural Practices plus Conservation Tillage ........................................................................................................... 10
Structural Practices .................................................................................................................................................... 11
Conservation Tillage ................................................................................................................................................... 14
Structural Practices and Conservation Tillage on Vulnerable Cropland ..................................................................... 17
Cultivated Cropland with No Structural Practices or Conservation Tillage ................................................................ 21
Conservation Crop Rotations and Cover Crops ............................................................................................................... 22
Conservation Crop Rotations ..................................................................................................................................... 22
Cover Crops ................................................................................................................................................................ 25
Irrigation .......................................................................................................................................................................... 27
Water Sources ............................................................................................................................................................ 29
Application Methods .................................................................................................................................................. 30
Application Efficiency ................................................................................................................................................. 33
Application Amount ................................................................................................................................................... 34
Nutrient Management..................................................................................................................................................... 35
Rate ............................................................................................................................................................................ 37
Method....................................................................................................................................................................... 37
Timing......................................................................................................................................................................... 39
Manure Application Trends ............................................................................................................................................. 41

HOW DID CONSERVATION ADOPTION AFFECT RESOURCE CONCERNS? .............................................................. 46
Erosion............................................................................................................................................................................. 46
Sheet and Rill Erosion................................................................................................................................................. 47
Wind Erosion .............................................................................................................................................................. 49
Sediment.......................................................................................................................................................................... 53
Surface Nitrogen.............................................................................................................................................................. 56
Sediment-Transported Phosphorus................................................................................................................................. 59
Subsurface Nitrogen ........................................................................................................................................................ 62
Soluble Phosphorus ......................................................................................................................................................... 64
Soil Carbon....................................................................................................................................................................... 67
Resource Concerns Summary .......................................................................................................................................... 71

HOW DID SEDIMENT AND NUTRIENT MANAGEMENT CHANGE?......................................................................... 73
Sediment.......................................................................................................................................................................... 73
Sediment Management by Tillage System ................................................................................................................. 74
Sediment Management on Vulnerable Acres ............................................................................................................ 77
Nitrogen........................................................................................................................................................................... 78
Nitrogen Management by Tillage System .................................................................................................................. 79
Nitrogen Management on Vulnerable Acres.............................................................................................................. 82
Phosphorus...................................................................................................................................................................... 83
Phosphorus Management by Tillage System ............................................................................................................. 84
Phosphorus Management on Vulnerable Acres......................................................................................................... 87

HOW DID THE CONSERVATION CONDITION IN THE CEAP SURVEYS COMPARE TO ALTERNATIVE TREATMENT
LEVELS?.............................................................................................................................................................. 89

Erosion Control and Nutrient Management (ENM)......................................................................................................... 89
Comparing Change in Cultivated Cropland Conservation Treatment Levels in CEAP Surveys ........................................ 91
Erosion Control and Nutrient Management Treatment (ENM) Effects by Treatment Need........................................... 92
How Did Conservation in CEAP I and CEAP II Compare to ENM? .................................................................................... 94
Erosion and Sediment ................................................................................................................................................ 95

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Conservation Effects Assessment Project
Nitrogen ..................................................................................................................................................................... 97
Phosphorus................................................................................................................................................................. 98
Soil Carbon ................................................................................................................................................................. 99
Summary .................................................................................................................................................................. 100

SUMMARY AND AGENCY ACTIONS................................................................................................................... 101
APPENDIX 1. OVERVIEW OF THE CEAP SAMPLING AND MODELING APPROACH ............................................... 103
APPENDIX 2. REGIONAL TABLES ....................................................................................................................... 106
APPENDIX 3. MANAGEMENT LEVELS CRITERIA ................................................................................................. 163

Tables
Table 1. Structural Practices, Conservation Tillage, and Both on Cultivated Cropland, CEAP I and CEAP II .................................... 10
Table 2. Structural Practice Adoption, CEAP I and CEAP II............................................................................................................... 13
Table 3. Tillage Groups and Classes, CEAP I and CEAP II ................................................................................................................. 14
Table 4. Highly Erodible Cropland by Treatment Group, CEAP I and CEAP II ................................................................................... 18
Table 5. Cultivated Cropland with High and Moderately High Runoff (SVI) Ratings by Treatment Group, CEAP I and CEAP II....... 20
Table 6. Cultivated Cropland with No Structural Practices or Conservation Tillage, CEAP I and CEAP II ........................................ 21
Table 7. Cultivated Cropland by Crop Rotation Group, CEAP II........................................................................................................ 23
Table 8. Cultivated Cropland by Crop Rotation Group and Tillage Group, CEAP II .......................................................................... 24
Table 9. Use of Cover Crops in Major Crop Rotation Groups, CEAP II.............................................................................................. 25
Table 10. Cover Crops and Conservation Crop Rotations by Major Crop Rotation Group, CEAP II .................................................. 26
Table 11. Cover Crop Use by Region, CEAP II ................................................................................................................................... 26
Table 12. Total Cropland, Irrigated Cropland, and Change in Irrigated Acres, CEAP I and CEAP II, Nationally and by Region........ 27
Table 13. Irrigation Water Applications, Total Water Applied, and Change in Water Applications, CEAP I to CEAP II, by Region.. 35
Table 14. Nutrients Applied on Cultivated Cropland, CEAP I and CEAP II ........................................................................................ 37
Table 15. Cultivated Cropland with Nutrients Applied by Type and Incorporation, CEAP I and CEAP II .......................................... 39
Table 16. Average Annual Nutrient Application Rates—Manured and Commercial Only............................................................... 42
Table 17. Cultivated Cropland with Manure Applied, by Source, CEAP I and CEAP II ...................................................................... 45
Table 18. Sheet and Rill Erosion by Threshold, CEAP I and CEAP II .................................................................................................. 47
Table 19. Cultivated Cropland with Sheet and Rill Erosion above T by Soil Vulnerability Runoff and Rainfall, CEAP II ................... 49
Table 20. Wind Erosion by Threshold, CEAP I and CEAP II ............................................................................................................... 51
Table 21. Cultivated Cropland with Wind Erosion above T by Soil Vulnerability Wind and Rainfall, CEAP II................................... 53
Table 22. Sediment Loss by Threshold, CEAP I and CEAP II.............................................................................................................. 55
Table 23. Cultivated Cropland Exceeding the Sediment Threshold by Soil Vulnerability Index Runoff and Rainfall, CEAP II........... 55
Table 24. Surface Nitrogen Loss by Threshold, CEAP I and CEAP II.................................................................................................. 56
Table 25. Cultivated Cropland Exceeding Surface Nitrogen Threshold by SVI Runoff and Rainfall, CEAP II .................................... 58
Table 26. Sediment-Transported Phosphorus Loss by Threshold, CEAP I and CEAP II ..................................................................... 59
Table 27. Cultivated Cropland Exceeding Sediment-Transported Phosphorus Threshold by SVI Runoff and Rainfall, CEAP II ........ 61
Table 28. Subsurface Nitrogen Loss by Threshold, CEAP I and CEAP II ............................................................................................ 62
Table 29. Cultivated Cropland Exceeding Subsurface Nitrogen Threshold by SVI Leaching (SVI-L) and Rainfall, CEAP II ................ 64
Table 30. Soluble Phosphorus Loss by Threshold, CEAP I and CEAP II.............................................................................................. 65
Table 31. Cultivated Cropland Exceeding Soluble Phosphorus Threshold by SVI Runoff and Rainfall, CEAP II ................................ 67
Table 32. Cultivated Cropland Exceeding the Soil Carbon Threshold by SVI Runoff and Rainfall, CEAP II ....................................... 70
Table 33. Nitrogen and Phosphorus Loss by Carbon Trend and Nutrient Management Level ........................................................ 70
Table 34. Cultivated Cropland Exceeding Resource Concern Thresholds by Survey......................................................................... 71
Table 35. Percent Regional Acres Exceeding by Threshold, CEAP II * .............................................................................................. 72
Table 36. Sediment Management Levels on Cultivated Cropland, CEAP I and CEAP II .................................................................... 74
Table 37. Sediment Management on Cultivated Cropland by Tillage System and CEAP Survey ..................................................... 76
Table 38. Sediment Management Levels by Soil Vulnerability Index Runoff (SVI-R), CEAP I and CEAP II ........................................ 77
Table 39. Nitrogen Management Levels on Cultivated Cropland, CEAP I and CEAP II..................................................................... 78
Table 40. Nitrogen Management on Cultivated Cropland by Tillage System and CEAP Survey ...................................................... 81
Table 41. Nitrogen Management Levels by Soil Vulnerability Index Leaching, CEAP I and CEAP II ................................................. 82
Table 42. Phosphorus Management Levels on Cultivated Cropland, CEAP I and CEAP II ................................................................ 83
Table 43. Phosphorus Management on Cultivated Cropland by Tillage System and CEAP Survey.................................................. 86
Table 44. Phosphorus Management on Cultivated Cropland by Soil Vulnerability Index Runoff (SVI-R) Rating, CEAP I and CEAP II
......................................................................................................................................................................................................... 87
Table 45. Estimated Percent of Cultivated Cropland Acres Meeting Resource Concern Thresholds under ENM, by Region........... 90
Table 46. Cultivated Cropland by Conservation Treatment Level, CEAP I and CEAP II..................................................................... 92
Table 47. Losses on Cultivated Cropland by Treatment Level and Resource Concern, CEAP II ........................................................ 92

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Table 48. Estimated Loss Reduction from CEAP II Baseline, by Loss Type and Treatment Level...................................................... 93
Table 49. Estimated Effects of ENM Treatment on Cultivated Cropland by Resource Concern and Treatment Need..................... 94
Table 50. Progress toward ENM by Resource Concern, CEAP I and CEAP II..................................................................................... 95

Figures
Figure 1. Change in Cropland Acreage by Region, CEAP I to CEAP II * .............................................................................................. 2
Figure 2. CEAP Production Regions, Cropland Concentration, and Annual Average Precipitation.................................................... 3
Figure 3. Change in Acreage of Selected Crops by Region and 12-Digit Hydrologic Unit, 2003–15 .................................................. 8
Figure 4. Cultivated Cropland by Treatment Group, CEAP I and CEAP II.......................................................................................... 11
Figure 5. Cultivated Cropland by Treatment Group and Region, CEAP I and CEAP II....................................................................... 12
Figure 6. Structural Practices by Group, CEAP I and CEAP II ............................................................................................................ 13
Figure 7. Cultivated Cropland by Tillage Class, CEAP I and CEAP II.................................................................................................. 15
Figure 8. HEL Cultivated Cropland by Treatment Group and Region, CEAP I and CEAP II................................................................ 19
Figure 9. Cultivated Cropland with High and Moderately High SVI Runoff Rating by Treatment Group, CEAP I and CEAP II ......... 20
Figure 10. Cultivated Cropland with No Structural Practices or Conservation Tillage by Region, CEAP I and CEAP II ..................... 21
Figure 11. Percent of Cultivated Cropland with Conservation Crop Rotations by Biomass Index (BI) Level and Region, CEAP I and
CEAP II ............................................................................................................................................................................................. 24
Figure 12. Cultivated Cropland by Combinations of Conservation Crop Rotations and Tillage, CEAP II .......................................... 24
Figure 13. Cultivated Cropland with Cover Crops, CEAP I and CEAP II ............................................................................................. 25
Figure 14. Cover Crop Use on Cultivated Cropland by Region, CEAP II ............................................................................................ 27
Figure 15. Acres of Irrigation on Cropland and Pastureland, 2017.................................................................................................. 28
Figure 16. Change in Irrigated Cropland by Region, CEAP I to CEAP II*........................................................................................... 29
Figure 17. Sources of Water for Irrigated Cropland, CEAP I and CEAP II ......................................................................................... 29
Figure 18. Water Sources for Irrigated Cropland, Nationally and by Region, CEAP I and CEAP II ................................................... 31
Figure 19. Irrigation Water Application Technology, Nationally and by Region, CEAP I and CEAP II .............................................. 31
Figure 20. National Irrigation Water Application Systems on Cropland, CEAP I and CEAP II........................................................... 32
Figure 21. Most Prevalent Regional Irrigation Water Application Systems on Cropland, CEAP I and CEAP II ................................. 32
Figure 22. VISE Efficiency Scores in CEAP I and CEAP II and Most Prevalent Technology in CEAP II, by Region .............................. 33
Figure 23. Irrigated Acreage Distribution of VISE Efficiencies by VISE Grouping and Region, CEAP I and CEAP II........................... 34
Figure 24. Change in Nitrogen and Phosphorus Application Rates by Region, CEAP II minus CEAP I.............................................. 37
Figure 25. Change in Incorporation Extent and Region, CEAP II minus CEAP I ................................................................................ 40
Figure 26. Total Applied Nutrients by Timing and Incorporation, CEAP I and CEAP II ..................................................................... 41
Figure 27. Nitrogen and Phosphorus Applied Load and Losses from Cultivated Cropland Receiving Manure Nutrients, CEAP II ... 43
Figure 28. Nitrogen and Phosphorus Applied to Manured Acres by Source and Region, CEAP II .................................................... 44
Figure 29. Seasonal Application of Manure Nutrients by Method, CEAP I and CEAP II ................................................................... 44
Figure 30. Sheet and Rill Erosion on Cultivated Cropland Relative to Threshold, CEAP I and CEAP II.............................................. 48
Figure 31. Cultivated Cropland Exceeding Sheet and Rill Erosion Threshold by SVI-R and CEAP Survey ......................................... 49
Figure 32. Wind Erosion on Cultivated Cropland Relative to Threshold, CEAP I and CEAP II ........................................................... 52
Figure 33. Cultivated Cropland Exceeding Wind Erosion Threshold by SVI-W and CEAP Survey ..................................................... 53
Figure 34. Cultivated Cropland and Sediment Load Relative to Sediment Threshold (Acres and Tons), CEAP I and CEAP II ........... 54
Figure 35. Cultivated Cropland Exceeding the Sediment Threshold by Region and SVI-R, CEAP I and CEAP II ................................ 56
Figure 36. Cultivated Cropland Relative to Surface Nitrogen Loss Threshold (Acres and Tons), CEAP I and CEAP II ....................... 57
Figure 37. Cultivated Cropland Exceeding the Surface Nitrogen Threshold by SVI-R and CEAP Survey........................................... 58
Figure 38. Cultivated Cropland Relative to Sediment-Transported Phosphorus Loss Threshold (Acres and Tons), CEAP I and CEAP
II....................................................................................................................................................................................................... 60
Figure 39. Cultivated Cropland Exceeding Sediment-Transported Phosphorus Threshold by Region and SVI-R, CEAP I and CEAP II
......................................................................................................................................................................................................... 61
Figure 40. Cultivated Cropland Relative to Subsurface Nitrogen Loss Threshold (Acres and Tons), CEAP II.................................... 63
Figure 41. Cultivated Cropland Exceeding Subsurface Nitrogen Threshold by SVI-L and CEAP Survey............................................ 64
Figure 42. Cultivated Cropland Relative to Soluble Phosphorus Loss Threshold (Acres and Tons), CEAP I and CEAP II ................... 66
Figure 43. Cultivated Cropland Exceeding Soluble Phosphorus Threshold by Region and SVI-R, CEAP I and CEAP II ...................... 67
Figure 44. Cultivated Cropland by Carbon Trend, CEAP I and CEAP II.............................................................................................. 68
Figure 45. Carbon Change by Region, CEAP I and CEAP II ............................................................................................................... 68
Figure 46. Carbon Trends by Tillage Class, CEAP II .......................................................................................................................... 69
Figure 47. Cultivated Cropland Exceeding the Carbon Threshold by Region and SVI-R, CEAP I and CEAP II.................................... 70
Figure 48. Cultivated Cropland by Sediment Management Level, CEAP I and CEAP II..................................................................... 74
Figure 49. Sediment Management Levels on Cultivated Cropland by Region, CEAP I and CEAP II .................................................. 75
Figure 50. Cultivated Cropland by Sediment Management Level and Tillage System, CEAP II minus CEAP I .................................. 76

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Figure 51. Change in Sediment Management on Cultivated Cropland by SVI-R, CEAP II minus CEAP I ........................................... 78
Figure 52. Cultivated Cropland by Nitrogen Management Level, CEAP I and CEAP II ..................................................................... 79
Figure 53. Nitrogen Management Levels on Cultivated Cropland, CEAP I and CEAP II.................................................................... 80
Figure 54. Nitrogen Management Level by Tillage System, CEAP II minus CEAP I........................................................................... 81
Figure 55. Change in Nitrogen Management on Cultivated Cropland by SVI-L, CEAP II minus CEAP I ............................................ 83
Figure 56. Cultivated Cropland by Phosphorus Management Level, CEAP I and CEAP II................................................................. 84
Figure 57. Phosphorus Management on Cultivated Cropland by Region, CEAP I and CEAP II ......................................................... 85
Figure 58. Cultivated Cropland by Phosphorus Management Level and Tillage System, CEAP II minus CEAP I .............................. 86
Figure 59. Change in Phosphorus Management on Cultivated Cropland by SVI-R, CEAP II minus CEAP I ....................................... 88
Figure 60. Erosion and Sediment Progress Toward ENM, CEAP I and CEAP II ................................................................................. 96
Figure 61. Progress toward Erosion and Sediment ENM by Loss Pathway and Region, CEAP II...................................................... 96
Figure 62. Surface and Subsurface Nitrogen Progress Toward ENM, CEAP I and CEAP II................................................................ 97
Figure 63. Progress toward Nitrogen ENM by Loss Pathway and Region, CEAP II .......................................................................... 98
Figure 64. Total and Soluble Phosphorus Progress toward ENM, CEAP I and CEAP II ..................................................................... 98
Figure 65. Progress toward Phosphorus ENM by Loss Pathway and Region, CEAP II...................................................................... 99
Figure 66. Soil Carbon Progress toward ENM, CEAP I and CEAP II................................................................................................... 99
Figure 67. Progress toward Soil Carbon ENM by Region, CEAP II .................................................................................................. 100

Boxes
Box 1. Structural Practice Groups and Types of Practices................................................................................................................ 13
Box 2. Tillage Effects on Fuel Consumption and Greenhouse Gas Emissions................................................................................... 16
Box 3. Soil Vulnerability Indexes ...................................................................................................................................................... 18
Box 4. Advances in Nutrient Technology ......................................................................................................................................... 36
Box 5. Soil Testing for Nutrient Management ................................................................................................................................. 38
Box 6. Controlling Erosion on Highly Erodible Land (HEL)................................................................................................................ 50
Box 7. Cover Crop Benefits............................................................................................................................................................... 69
Box 8. Treatment Needs at the Field Level ...................................................................................................................................... 72

CEAP National Report:
Conservation Practices on Cultivated
Cropland
INTRODUCTION
The U.S. Department of Agriculture’s (USDA) N atural Resources Conservation Service (NRCS)
evaluates conservation trends and effects on cultivated cropland through the multiagency
Conservation Effects Assessment Project (CEAP) , a sampling and modeling approach drawing
on natural resource data and farmer surveys (appendix 1) . The farmer surveys are conducted
jointly by USDA’s NRCS and National Agricultural Statistics Service (NASS). T he first surveys
were completed in 2003–06 (CEAP I), w ith basinwide reports released from 2010 through 2014.
Now, comparison data from the second set of farmer surveys (2013–16; CEAP II) m ake it
possible to evaluate change over a decade.
CEAP is intended to contribute to the science base for managing the agricultural landscape for
environmental quality. Findings are intended to help guide conservation policy and program
development and help conservationists, farmers, and ranchers in their conservation decisions.
The purpose of this report is to present the CEAP I and CEAP II data on conservation practices
applied on cultivated cropland at national and in some cases regional levels, estimates of the
effects of these practices, and how conservation activity may have changed over the decade. The
data reflect only the presence or absence of the practice; they do not indicate if the practice is
pre-existing and maintained, reconstructed, or newly installed.

CEAP Production Regions
Estimates in this report are presented for 11 CEAP production regions, which reflect prevalent
land use, cropping systems, climate, soil characteristics, and conservation practice use. The first
CEAP reports (CEAP I) pre sented results by regions representing the major drainage basins in
the United States (Water Resource Regions). The CEAP II regions reduce the variability in
cropping systems, conservation and production practices, and resource concerns found in the
CEAP I regions. The rules of analysis were unchanged between the CEAP survey periods, but
the CEAP I sample points were reaggregated into the new regions presented in this report. For
some regions with small amounts of cultivated cropland or where production systems and natural
resource factors affect the opportunity or need for adoption of these practices, slight changes
cannot be reliably estimated.
Over the decade between the two CEAP survey periods, there was a small net gain in cultivated
cropland of more than 2 million acres, primarily coming from pastureland and cropland exiting

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Conservation Effects Assessment Project

the Conservation Reserve Program (CRP).1 Five regions gained almost 7.5 million cultivated
cropland acres, while six regions lost about 5.3 million acres combined (fig. 1). By CEAP II,
three regions (North Central and Midwest, Southern and Central Plains, and Northern Plains)
accounted for three-fourths of all U.S. cultivated cropland (fig. 2; appendix 2, table A-1).
Figure 1. Change in Cropland Acreage by Region, CEAP I to CEAP II

Note: Number in parentheses indicates acreage change as a percent of the region’s CEAP I cultivated cropland level.

The following provides generalized overviews of production and natural resource factors for
each CEAP region to give context for the trends presented in this report.
California Coastal: Cultivated cropland accounts for 3.9 million acres, less than 10 percent of
the region’s total land area and about 1 percent of all cultivated cropland in the United States.
Cultivated cropland is concentrated in the level to gently rolling valleys, which have lower
vulnerability to wind and water erosion. With its dry Mediterranean climate, water management
and irrigation practices are higher priorities than erosion control within fields or at their edges.
Production on cultivated cropland is dominated by high-value crops such as rice, fruits, and
vegetables. Production practices, pest and disease control measures, and industry requirements
for the fresh market reduce producers’ ability to adopt conservation tillage on a continuous basis.

1
See tables 6 and 7 of U.S. Department of Agriculture. 2020. Summary Report: 2017 National Resources Inventory, Natural
Resources Conservation Service, Washington, DC, and Center for Survey Statistics and Methodology, Iowa State University,
Ames, Iowa. https://www.nrcs.usda.gov/sites/default/files/2022-10/2017NRISummary_Final.pdf

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Figure 2. CEAP Production Regions, Cropland Concentration, and Annual Average Precipitation

Note: The dot density shows concentrations of cultivated cropland within the region while the shading reflects the precipitation.

Southwest: Cultivated cropland accounts for nearly 3.2 million acres, or less than 1 percent of
the region’s total land area and less than 1 percent of all cultivated cropland in the United
States. With an arid climate, water erosion vulnerability is low, while water management and
irrigation practices are higher conservation priorities. Less than 10 percent of cultivated cropland
acres have high or moderately high runoff risk when rains occur. Wind erosion is the primary
erosion concern. High-tillage crops such as cotton, root crops, and vegetables along with land
levelling and land shaping for irrigation limit adoption of continuous conservation tillage.
Northwest: Cultivated cropland accounts for 13.4 million acres, but less than 5 percent of the
region’s total land area and about 4 percent of all cultivated cropland in the United States. The
region has a largely semiarid to arid climate that minimizes the need for water-induced erosion
control. Wind erosion poses more of an erosion challenge. The significant increase in
conservation tillage between the two CEAP survey periods is the primary wind-erosion-control
measure. Wheat and other close-grown crops dominate cultivated cropland production and
provide opportunities for the adoption of conservation tillage. Portions of the region where
acreage is irrigated and root crops such as potatoes are produced have limited opportunities for
continuous conservation tillage.
Northern Plains: Cultivated cropland accounts for 51.1 million acres, or about 27 percent of
the region’s total land area and about 16 percent of all cultivated cropland in the United States.

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Conservation Effects Assessment Project

The region’s semiarid to subhumid climate, coupled with the fact that only about a fourth of the
acres have high or moderately high runoff risk, reduces need for extensive structural practice
adoption. In contrast, 44 percent of acres have a high or moderately high wind erosion risk, but
the dominance of close-grown crops and conservation tillage provides significant control.
Southern and Central Plains: Cultivated cropland accounts for 62.7 million acres, or about 28
percent of the region’s total land area and about 20 percent of all cultivated cropland in the
United States. With periods of seasonal drought and high-energy convective storms often
producing high-intensity rainfall and flash floods, regional water quantity concerns need to be
balanced with vegetated structural practices for wind and water erosion control. In the semiarid
parts of the region, use of seasonal conservation tillage (e.g., crop rotations with small grains
providing seasonal erosion control) is the primary wind erosion control method, while in the
higher rainfall areas, structural conservation practice options are needed. The significant cotton
acreage characterized by intense tillage, partially to control pests (e.g., boll weevil), reduces the
viability of continuous conservation tillage in the southern part of the region. However, rotations
with corn and small grains provide some seasonal tillage system flexibility. The northern part of
the region is dominated by small grains conducive to conservation tillage adoption, although root
crop (e.g., sugar beets) production here is also associated with intense tillage.
North Central and Midwest: Cultivated cropland accounts for about 123.3 million acres, or
about 44 percent of the region’s total land area and about 39 percent of all cultivated cropland
in the United States. The region’s high-rainfall climate and the intensity of agricultural
production drives higher adoption of one or more structural practices and conservation tillage to
address multiple resource concerns. The sloping landscapes in the region may require more than
one structural practice supported by conservation tillage, while conservation tillage alone may be
adequate to control erosion in the lower lying areas, which tend to be drained and more prone to
subsurface losses. The size and concentration of agriculture in this region significantly influences
many of the national trends in adoption of structural practices and conservation tillage adoption.
South Central: Cultivated cropland accounts for 5.1 million acres, or less than 5 percent of the
region’s total land area and about 2 percent of all cultivated cropland in the United States. The
generally sloping landscapes and humid, high-rainfall climate drives adoption of one or more
structural conservation measures to control runoff. Cotton production in the region also reduces
the opportunities for conservation tillage, resulting in the need for more than one structural
practice on many acres to control erosion and sediment loss.
Lower Mississippi and Texas Gulf Coast: Cultivated cropland accounts for 20.9 million acres,
or nearly one-third of the region’s land area and about 7 percent of all cultivated cropland in
the United States. The humid and subtropical climate, nearly flat slopes with tile drainage, and
rolling loess hills adjacent to floodplains create conditions for excessive sediment loss and the
need for multiple structural practices and minimal tillage practices with high-residue crop
rotations. The prevalence of intense-tillage cotton and rice production reduces conservation
tillage opportunities and increases reliance on structural practices.
East Central: Cultivated cropland accounts for over 10.2 million acres, or about 17 percent of
the region’s land area and about 3 percent of all cultivated cropland in the United States. The

Conservation Practices on Cultivated Cropland

5

humid climate with rolling topography often requires adoption of structural practices along with
conservation tillage to control erosion and runoff. The high adoption of conservation tillage and
particularly no-till reflect the dominance of corn-soybean-wheat rotations in the region.
Atlantic and Gulf Coastal Plains: Cultivated cropland accounts for 13.8 million acres, just
under 10 percent of the region’s land area and about 4 percent of all cultivated cropland in the
United States. The humid, high-rainfall climate increases the need for edge-of-field structural
practices to reduce losses on the two-thirds of acres with high to moderately high leaching risk,
despite nearly level slopes. While less than 15 percent of acres have high or moderately high
runoff risk, multiple structural practices generally are needed because of the high rainfall. The
use of complex rotations with high-residue crops offset some effects associated with intense
tillage systems on cotton and peanut production in the region, but structural practices are often
necessary.
Northeast: Cultivated cropland accounts for almost 7.6 million acres, just under 7 percent of the
region’s land area and about 2 percent of all cultivated cropland in the United States. The
northern part of the region has little cropland, and what is there is typically corn for silage and
root and vegetable crops on hilly landscapes, which drives a need for multiple structural
practices especially when conservation tillage is not used. The humid climate, more intense
agriculture on hilly landscapes, and high proportion of acres receiving animal manures in the
southern part of the region benefit from combinations of structural practices with conservation
tillage.

A Changing Agricultural Landscape
Significant changes in agricultural management and production occurred over the decade in
response to a variety of factors and provide additional context for the trends presented in this
report. The changes are interrelated, manifesting in significant shifts in where crops are produced
because of expanded growing seasons, advances in technology, and market signals. Moreover,
the production environment continues to change; consider the current, historic drought
conditions in the West and the continuing evolution of agri-environmental policies.
Farms and Ownership
The long-term shift toward larger, more specialized farms is part of a complex set of structural
changes in agriculture. In the early 1980s, most cropland was operated by farms with less than
600 crop acres, today most cropland is on farms with at least 1,100 acres. Field crop operations
increasingly grow just two or three crops.2
Specialization also separated crop and livestock production, which continued to shift toward
larger, more geographically concentrated enterprises that produced no crops and relied on
purchased feed. The geographic separation of livestock from cropland drove a nutrient imbalance
between the two, reducing opportunities for manure nutrients to be used productively, and
creating incentives for overapplication of manure nutrients as a waste disposal solution. 3,4
https://www.ers.usda.gov/publications/pub-details/?pubid=45110
https://www.ers.usda.gov/publications/pub-details/?pubid=45110
4 https://www.ers.usda.gov/publications/pub-details/?pubid=44294
2
3

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Conservation Effects Assessment Project

Despite shifts toward larger, more specialized farms, family farms continue to dominate crop
agriculture. Family farms as a group accounted for 98 percent of farms and 86 percent of
production in 2019. Most family farms are small;5 they operate almost one half of all farmland
but account for only 22 percent of production. Large-scale family farms accounted for less than 3
percent of farms, 21 percent of farmland, but 44 percent of the value of production.6
While most of all U.S. farmland is owner-operated, more than half of cropland was rented in
2017, compared with just over 25 percent of pastureland. In general, rental activity is
concentrated in grain production areas; cash grains such as rice, corn, soybeans, wheat, and
cotton.7 Most rented acres are owned by non-operator landlords, often with little connection to
agriculture.
Cropping Patterns
Since the 1990s, U.S. farmers have been increasing corn and soybean acreage while decreasing
acreage of other widely grown crops, particularly wheat. The Federal Agriculture Improvement
and Reform (FAIR) Act of 1996 allowed farmers to change crops without loss of farm program
eligibility, helping to ensure that crop acreage decisions would be based on market signals rather
than farm program benefits. In the late 1990s, soybean acreage increased while wheat acreage
decreased, reflecting changes in the relative profitability of these crops.8
The shift accelerated in the late 2000s as increasing demand for feed and fuel and a spike in
export demand led to higher corn and soybean prices. Relative to wheat, corn prices were
particularly high, peaking at about 90 percent of wheat in 2010–12. Soybean prices were also
high relative to wheat during this period, peaking at 195 percent of wheat prices in 2009–10.
From 1992 to 2015, corn and soybeans increased from 41 percent to 54 percent of cultivated
cropland nationally. Corn and soybean acreage increased in the western Corn Belt (Missouri,
Iowa, Southwestern Minnesota, Eastern Nebraska, and Eastern South Dakota), the Great Plains
(Texas, Oklahoma, Kansas, North Dakota, and Western South Dakota), the Northern and
Northeastern states (Northwestern Minnesota, Wisconsin, Pennsylvania, and New York), and
many parts of the South (fig. 3;pages 8 and 9 appendix 2, table A-2). Wheat acreage declined
within traditional Corn Belt states (Ohio, Indiana, Illinois, Missouri, and Iowa) and along the
eastern edge of the Great Plains (Texas, Oklahoma, Kansas, Nebraska, and the Dakotas), while
increasing along the eastern seaboard and in some parts of Tennessee, Kentucky, and Alabama.
Cotton production declined or was unchanged in all major cotton producing regions.
Prevailing Weather
Changes in temperature and precipitation altered growing conditions, making areas to the west
and north of the traditional Corn Belt more favorable for corn and soybean production. In dryer
regions, the moisture conservation benefits of conservation tillage (especially no-till) may have
been important in expanding corn and soybean acreage. In the Great Plains and across the
The Farm Typology developed by USDA’s Economic Research Service identifies small family farms as those with less than
$350,000 in gross cash farm income.
6 https://www.ers.usda.gov/publications/pub-details/?pubid=100011
7 https://www.ers.usda.gov/publications/pub-details/?pubid=74675
8 Zulauf, Carl and Melissa R. Wright. 2001. “The Law of Unintended Consequences.” Choices, Second Quarter: 20–24.
5

Conservation Practices on Cultivated Cropland

7

northern tier of states, growing seasons were 9 to 10 days longer, on average, during 1991–2012
than during 1901–60.9 During similar time periods, in the eastern Great Plains, where lack of
moisture has been a barrier to corn and soybean production, overall precipitation has increased
by 10 to 20 percent. Further, the proportion of precipitation received in the heaviest 1 percent of
precipitation events increased by 42 percent in the Northern Plains and by 24 percent in the
Southern Plains.10 The increase in precipitation intensity may increase runoff, making some of
the additional moisture unavailable to crops as well as increasing the potential for loss of
sediment and nutrients from farm fields.
Production Technology
Advances in plant breeding technology, pest management, and other management techniques
have increased productivity and production efficiencies. For example:
●
●
●
●

Continuous improvement in corn genetics have contributed to steady increases in corn yields.
Shorter season corn varieties, which can be grown at higher latitudes and depend less on lateseason moisture, helped expand corn production west and north.
Drought-tolerant varieties reduced the risk of crop loss in mild drought conditions and have been
most widely used in states that experience relatively frequent periods of mild to moderate
drought.11
The availability of herbicide tolerant (HT) corn and soybeans simplified weed control with
reduced tillage, increasing the use of all types of conservation tillage.12

However, the rapid advances in crop genetics have outpaced research on fertilizer
recommendations, creating a lag that will tend to slow the realization of the environmental
benefits of these more efficient crop genetics.
The use of guidance systems on tractors, combines, and in other field operations has become
more commonplace, accompanied by variable-rate fertilizer application technology that matches
fertilizer rates to different soil zones and conditions within a field. Enhanced-efficiency
fertilizers (EEF) include additives and formulations designed to control and better time the
nutrient release of commercial fertilizers to meet crop demand and improve nutrient-use
efficiency. The technology has largely been focused on nitrogen with the aim of reducing losses
from ammonia volatilization and, after mineralization, to leaching, immobilization, and
denitrification. These technologies make the farm operation more efficient in its fertilizer use and
reduce potential losses.

Walsh, J., D. Wuebbles, K. Hayhoe, J. Kossin, K. Kunkel, G. Stephens, P. Thorne, R. Vose, M. Wehner, J. Willis, D. Anderson, S.
Doney, R. Feely, P. Hennon, V. Kharin, T. Knutson, F. Landerer, T. Lenton, J. Kennedy, and R. Somerville, 2014: Ch. 2: Our
Changing Climate. Climate Change Impacts in the United States: The Third National Climate Assessment, J. M. Melillo, Terese
(T.C.) Richmond, and G. W. Yohe, Eds., U.S. Global Change Research Program, 19-67.
10 Hayhoe, K., D.J. Wuebbles, D.R. Easterling, D.W. Fahey, S. Doherty, J. Kossin, W. Sweet, R. Vose, and M. Wehner, 2018: Our
Changing Climate. In Impacts, Risks, and Adaptation in the United States: Fourth National Climate Assessment, Volume II
[Reidmiller, D.R., C.W. Avery, D.R. Easterling, K.E. Kunkel, K.L.M. Lewis, T.K. Maycock, and B.C. Stewart (eds.)]. U.S. Global
Change Research Program, Washington, DC, USA, pp. 72–144.
11 McFadden, Jonathan, David Smith, Seth Wechsler, and Steven Wallander. 2019. “Development, Adoption, and Management
of Drought-Tolerant Corn in the United States.” USDA Economic Research Service, Economic Information Bulletin EIB-204,
November.
12 Perry, Edward D., Gian Carlo Moschini, and David A. Hennessy. 2016. “Testing for Complementarity: Glyphosate Tolerant
Soybeans and Conservation Tillage.” American Journal of Agricultural Economics 98 (3): 765–84.
9

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Conservation Effects Assessment Project

Figure 3. Change in Acreage of Selected Crops by Region and 12-Digit Hydrologic Unit, 2003–15

Conservation Practices on Cultivated Cropland
Figure 3. Change in Acreage of Selected Crops by Region and 12-Digit Hydrologic Unit, 2003–15—Cont.

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Conservation Effects Assessment Project

HOW DID THE USE OF CONSERVATION PRACTICES CHANGE
BETWEEN THE CEAP SURVEYS?
In the decade between the CEAP surveys, adoption of structural practices and conservation
tillage increased significantly, closely aligned with rising corn and soybean acreage.
Conservation crop rotations were used on a majority of cultivated cropland, and the use of cover
crops expanded. Irrigated cropland also increased, accompanied by efficiency gains that led to
reduced water use. Nutrient management was challenged to keep pace with tillage and cropping
changes and experienced some overall declines reflecting the complex interaction with
conservation tillage systems.

Structural Practices and Conservation Tillage
Farmer adoption of structural practices (e.g., terraces, grassed waterways, see box 1, page 13)
and conservation tillage, alone or in combination, increased by nearly 42 million acres
nationwide between the two CEAP surveys. By CEAP II, one or more of these conservation
practices were in place on over 81 percent of all cultivated cropland, up from 68 percent in
CEAP I (table 1; appendix 2, table A-3). Acres without conservation tillage or structural
practices declined significantly by 39.5 million acres to 19 percent of all cultivated cropland.
Table 1. Structural Practices, Conservation Tillage, and Both on Cultivated Cropland, CEAP I and CEAP II
CEAP I
Treatment Group

Acres
(1,000s)

Percent
of Acres

CEAP II
Acres
(1,000s)

Percent
of Acres

CEAP II minus
CEAP I *
Acres
(1,000s)

Percent
of Acres

Percent
Change in
Acres
Relative to
CEAP I

Structural Practices, Conservation
212,414
68
254,155
81
41,742
13
20
Tillage, or Both
Structural Practices plus Conservation
64,860
21
107,489
34
42,630
13
66
Tillage
Conservation Tillage Only
92,265
29
103,042
33
10,778
3
12
Structural Practices Only
55,289
18
43,623
14
-11,666
-4
-21
No Structural Practices or
100,651
32
61,148
19
-39,503
-13
-39
Conservation Tillage
National
313,065
100
315,303
100
2,238
* Ninety-five-percent confidence intervals were constructed for each survey period; overlap of the intervals was considered to
indicate no difference between the means. Unless noted, values fall within the 95-percent confidence interval.

Structural Practices plus Conservation Tillage
The greatest gains were made in the structural practices plus conservation tillage treatment
group, evidence that farmers were increasingly integrating conservation management and
structural treatments in a systems approach to improve results on their operations. By CEAP II,
the combined practices had increased by 66 percent and were in place on over 107 million acres,
or 34 percent of all cultivated cropland (fig. 4).

Conservation Practices on Cultivated Cropland

11

Figure 4. Cultivated Cropland by Treatment Group, CEAP I and CEAP II

Adoption of structural practices and conservation tillage was highly concentrated in the North
Central and Midwest and the Southern and Central Plains regions, which together accounted for
about 72 percent of the total increase (fig. 5). Nationally, structural practices integrated with
conservation tillage increased by 13 percentage points over the decade.
Structural Practices
Between CEAP I and CEAP II, an additional 31 million acres were benefited by structural
practices, largely in combination with conservation tillage as the use of structural practices alone
declined by 11.7 million acres (see box 1, page 13). By CEAP II, nearly half of all cultivated
cropland acres had one or more structural practices in place (table 2; appendix 2, table A-4).
Multiple structural practices accounted for 77 percent of the increase in adoption between CEAP
I and CEAP II as farmers applied supporting practices in a systems approach to reduce soil
erosion and related losses from cultivated cropland. More than half (56 percent) of the total
national increase occurred in the North Central and Midwest region, where an additional 17.3
million acres benefited from application of one or more structural practices.
Of the five structural practice groups used on cultivated cropland (box 1), field borders (at least
30 feet wide) experienced the largest acreage gain between the two survey periods as well as the
largest percent gain relative to CEAP I implementation levels (fig. 6). Overland flow and
concentrated flow control practices, however, maintained the largest footprint in both survey
periods, reflecting their long history as erosion-control tools on farm fields (see also appendix 2,
table A-5).

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Conservation Effects Assessment Project

Figure 5. Cultivated Cropland by Treatment Group and Region, CEAP I and CEAP II

Conservation Practices on Cultivated Cropland

13

Box 1. Structural Practice Groups and Types of Practices
Five structural practice groups were established based on their primary conservation objective to facilitate evaluating change
between the CEAP survey periods. The groups and example practices include:
● Field border—Strips of permanent vegetation (grasses, legumes, forbs, or shrubs) established on one or more sides of a
field
● Edge-of-field buffering and filtering—Riparian forest buffers, riparian herbaceous buffers, filter strips, critical area
planting
● Wind erosion control—Windbreaks or shelterbelts, herbaceous wind barriers, hedgerow plantings
● Concentrated flow control—Grassed waterways, grade stabilization structures, diversions, structures for water control
● Overland flow control—Terraces, contour buffer strips, contour farming, stripcropping, in-field vegetative barrier.

Table 2. Structural Practice Adoption, CEAP I and CEAP II
CEAP I
Cultivated Cropland with:

One or More Structural
Practices
One Type of Structural Practice
More than One Type of Structural
Practice

CEAP II

CEAP II - CEAP I
Percent
Change in
Acres
Percent
Acres
(1000s)
Relative to
CEAP I

Acres
(1000s)

Percent

Acres
(1000s)

Percent

120,149

38

151,113

48

30,964

10

26

68,485

22

75,619

24

7,134

2

10

51,664

17

75,494

24

23,830

7

46

Figure 6. Structural Practices by Group, CEAP I and CEAP II

Note: CEAP II bar notations reflect the percent increase in acreage relative to the CEAP I implementation level.

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Conservation Effects Assessment Project

Conservation Tillage
The change in conservation tillage was particularly striking. Compared to conventional tillage,
conservation tillage systems reduce soil disturbance, promote development of soil organic
matter, reduce potential for compaction, and increase soil moisture holding capacity and
infiltration, among other benefits. CEAP established five tillage classes based on average annual
Soil Tillage Intensity Rating (STIR) values,13 which were placed into two groups for analysis:
●

●

Conservation Tillage
o Reduced Tillage includes:
▪ Continuous Mulch Tillage: All crops in the rotation are produced under tillage
with STIR values for each crop between 20 and 80. Mulch tillage includes all
forms of conservation tillage that are not considered no-till.
▪ Seasonal No-Till: At least one crop is produced with no-till (STIR <20) and no
crop in the rotation is conventionally tilled (STIR>80).
o Continuous No-Till: All crops in the rotation are produced with tillage practices having
STIR values <20.
Conventional Tillage
o Continuous Conventional Tillage: All crops in the rotation are conventionally tilled
(STIR >80).
o Seasonal Conventional Tillage: At least one crop in the rotation is conventionally tilled
(STIR>80) and at least one crop is conservation tilled (STIR<80).

In the decade between the CEAP surveys, conservation tillage adoption increased by 53.4
million acres (table 3; appendix 2, table A-6). Eighty percent of this increase was in combination
with structural practices (see also table 1, page 10). By CEAP II, conservation tillage had
become the dominant form of tillage, used on over two-thirds of all cultivated cropland (67
percent). More than 41.5 million acres of the total increase was in continuous no-till, which
reached 33 percent of all cultivated cropland acres by CEAP II (fig. 7). As a result, farmers were
able to reduce annual average fuel consumption in tillage processes by 110 million gallons of
diesel fuel equivalents and avoid the associated annual greenhouse gas emissions by nearly 1.2
million tons of carbon dioxide equivalents (CO2-eq) by CEAP II (see box 2, page 16).
Table 3. Tillage Groups and Classes, CEAP I and CEAP II
Percent
Change in
Tillage Group / Tillage
Acres
Class
Acres
Acres
Acres
Relative to
Percent
Percent
Percent
(1,000s)
(1,000s)
(1,000s)
CEAP I
Conservation Tillage
157,124
50
210,532
67
53,408
17
34
Continuous Mulch
50,631
16
60,212
19
9,581
3
19
Seasonal No Till
44,941
14
47,211
15
2,271
1
5
Continuous No-Till
61,553
20
103,108
33
41,556
13
68
Conventional Tillage
155,941
50
104,771
33
-51,169
-17
-33
Continuous Conventional
62,922
20
42,052
13
-20,869
-7
-33
Seasonal Conventional
93,019
30
62,719
20
-30,300
-10
-33
* Ninety-five-percent confidence intervals were constructed for each survey period; overlap of the intervals was considered to
indicate no difference between the means. Unless noted, values meet the 95-percent confidence interval.
CEAP I

13

CEAP II

CEAP II minus
CEAP I *

STIR is a function of the type, frequency, and depth of tillage and calculates soil disturbance intensity for each
crop grown in a crop rotation. The higher the rating, the greater the soil disturbance and erosion potential.

Conservation Practices on Cultivated Cropland
Figure 7. Cultivated Cropland by Tillage Class, CEAP I and CEAP II

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Conservation Effects Assessment Project

Box 2. Tillage Effects on Fuel Consumption and Greenhouse Gas Emissions
Among the many benefits of conservation tillage systems as compared to conventional tillage are the reductions in the number
of field operations and associated soil disturbance, fuel consumption, and greenhouse gas emissions. Between CEAP I and CEAP
II, cultivated cropland increased by over 2 million acres, conservation tillage systems increased by over 53 million acres, and
conventional tillage systems declined by over 51 million acres. Correspondingly, fuel use grew in conservation tillage and
dropped in conventional tillage. The upshot is that by CEAP II, farmers were cultivating slightly more cropland while using less
fuel and producing fewer emissions; annual fuel consumption on all cultivated cropland declined by 110 million gallons of diesel
fuel equivalents and annual emissions declined by nearly 1.2 million tons of carbon dioxide equivalents (CO2-eq).
Fuel Use and Emissions by Tillage System, CEAP I to CEAP II
CEAP I (2003–06)
CEAP II (2013–16)
Total Fuel
Total Fuel
Tillage System
Consumption
Consumption
Acres\
Acres\
(Million gallons
(Million gallons
(Million)
(Million)
Diesel equiv.)
Diesel equiv.)

CEAP II minus CEAP I
Fuel
Consumption
(Million gallons
Diesel equiv.)

Emissions
Reductions
(Million tons
CO2 equiv)**

Continuous Conventional
62.9
340.0
42.1
226.0
-114.0
-1.3
Seasonal Conventional *
93.0
328.0
62.7
226.0
-102.0
-1.1
Reduced Tillage
95.5
266.0
107.4
298.0
32.0
0.4
Continuous No Till
61.6
114.0
103.1
188.0
74.0
0.8
Total
313.1
1,048.0
315.3
938.0
-110.0
-1.2
* Seasonal conventional is presented separately here because of differences in fuel consumption compared to continuous
conventional tillage.
** Based on 22.4 pounds of CO2-eq per gallon of diesel fuel equivalents.
Assuming uniform transition over the decade, the adoption of conservation tillage had an estimated cumulative effect of
reducing:
● Fuel consumption by up to 600 million gallons of diesel fuel equivalents, enough to meet the annual electricity
requirements of nearly 2.3 million average households in the United States.14
● Emissions by up to 6.6 million tons of CO2-eq., enough to offset the annual CO2-eq emissions of about 1.4 million
passenger cars, or nearly all the passenger cars registered in the state of Louisiana.15
● Fuel costs borne by farmers by up to $1.8 billion.16
These effects, however, mask the significant difference between conservation tillage and continuous conventional tillage in
terms of fuel use and emissions. If the nearly 273 million acres of cultivated cropland under conservation tillage and seasonal
conventional systems in CEAP II had been under continuous conventional tillage, it would have required an additional 763
million gallons of diesel fuel equivalents per year, and that additional fuel would have had associated emissions of roughly 8.5
million tons of CO2-eq. For context, the additional fuel is equal to the annual energy needed for over 2.8 million average
households in the United States.17 The associated CO2-eq emissions is equal to that of nearly 1.7 million passenger cars, or
slightly less than all the passenger cars in the state of Colorado. 18

As calculated by converting the estimated diesel fuel equivalents reduced to kilowatt hours. According to the U.S. Energy
Information Administration the average household electricity use is 10,649 kWh annually.
https://www.eia.gov/energyexplained/units-and-calculators/energy-conversion-calculators.php
15 Based on emissions from an average passenger vehicle, https://www.epa.gov/energy/greenhouse-gas-equivalenciescalculator. Number of passenger vehicles as reported in 2015 according to data from the Federal Highway Administration.
https://www.fhwa.dot.gov/policyinformation/statistics/2015/mv1.cfm
16 Based on an average price of $2.94 per gallon for diesel fuel between 2003 and 2016, as reported by the U.S. Energy
Information Administration. https://www.eia.gov/dnav/pet/pet_pri_gnd_dcus_nus_a.htm
17 As calculated by converting the estimated diesel fuel equivalents reduced to kilowatt hours. According to the U.S. Energy
Information Administration the average household electricity use is 10,649 kWh annually.
https://www.eia.gov/energyexplained/units-and-calculators/energy-conversion-calculators.php
18 Based on emissions from an average passenger vehicle, https://www.epa.gov/energy/greenhouse-gas-equivalenciescalculator. Number of passenger vehicles as reported in 2015 according to data from the Federal Highway Administration.
https://www.fhwa.dot.gov/policyinformation/statistics/2015/mv1.cfm
14

Conservation Practices on Cultivated Cropland

17

And farmers would have faced between $1.8 billion and $3 billion in additional fuel costs.19 Roughly 80 percent of that
additional fuel need would have been concentrated in three regions—North Central and Midwest, Northern Plains, and
Southern and Central Plains.
Estimated Annual Reduction in Fuel Use and Emissions by Conservation Tillage and Seasonal Conventional Tillage Systems as
Compared to Continuous Conventional Tillage, CEAP II
Cultivated Cropland
Tillage Type
Total Fuel
Average Fuel Use Avoided Emissions Avoided
Consumption
Fuel
(Million gallons
(Million tons CO2
Acres
Acres
Diesel equiv.)*
equiv) **
(Millions
(Percent (Million gallons Use/Acre
Diesel equiv.)
)
Continuous Conventional
42.1
13.4
226.0
5.4
Seasonal Conventional
62.7
19.9
226.0
3.6
112.6
1.3
Reduced Tillage
107.4
34.1
298.0
5.5
282.0
3.2
Continuous No Till
103.1
32.7
188.0
1.8
368.7
4.1
Total
315.3
100.0
938.0
16.3
763.3
8.5
* Potential annual reduction in fuel consumption as compared to a continuous conventional tillage system with STIR >80.
** Based on 22.4 pounds of CO2-eq per gallon of diesel fuel equivalents.

The Southern and Central Plains, characterized by winter wheat and other close-grown small
grains, accounted for 40 percent of the total increase in conservation tillage adoption. The North
Central and Midwest region (dominated by corn and soybean production) accounted for another
31 percent. Nationally, conservation tillage adoption increased by 17 percentage points between
the survey periods. That gain was exceeded in four regions, with the Southern and Central Plains
region being twice the national average.
Structural Practices and Conservation Tillage on Vulnerable Cropland
The cultivated cropland most vulnerable to excessive soil erosion (Highly Erodible Land [HEL])
and runoff (high and moderately high Soil Vulnerability Index [SVI] runoff) account for about
27 percent and 29 percent of all cultivated cropland, respectively (box 3). Conservation adoption
on these acres emphasized structural practices in combination with conservation tillage. In
addition, these vulnerable acres received a slightly higher proportion of treatment compared to
their less vulnerable counterparts. By CEAP II, structural practices or conservation tillage, or
both, were in place on 85 percent of HEL cultivated cropland and on over 90 percent of
cultivated cropland with high or moderately high runoff vulnerability, as compared to 81 percent
for all cultivated cropland.
Highly Erodible Land—The 1985 Farm Bill introduced policy to encourage conservation on
cropland deemed to be the most susceptible to excessive erosion (Highly Erodible Land [HEL])
by linking farm program eligibility to implementation of soil conservation measures. Between
CEAP I and CEAP II, adoption of structural practices plus conservation tillage on HEL increased
by 13.9 million acres (63 percent) (table 4, fig. 8; appendix 2, table A-7). Use of conservation
tillage without structural practices also increased by nearly 6.8 million acres (32 percent), while
use of structural practices alone declined by 4.9 million acres (35 percent). Adoption of these
practices increased by 12 percentage points over the decade, despite a 7.4-million-acre increase
in HEL under cultivation.

Based on average prices of $3.9 per gallon for diesel fuel in 2013 and $2.4 per gallon in 2016, as reported by the U.S. Energy
Information Administration. https://www.eia.gov/dnav/pet/pet_pri_gnd_dcus_nus_a.htm

19

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Conservation Effects Assessment Project

Box 3. Soil Vulnerability Indexes
NRCS developed Soil Vulnerability Indexes (SVI) in the 2000s to support conservation planning through rigorous assessment of
soil vulnerability to the forces of water (runoff, leaching) and wind. SVI uses current information on soil properties as well as
other aspects of vulnerability such as slope and drainage. Four ratings (low, moderate, moderately high, and high) are used to
categorize a soil’s potential vulnerability. The index is regionally relative; for example a high runoff rating in an arid region
would not have the same conservation need as a high runoff rating in a humid region. Examining cropland by potential
vulnerability offers an important tool for identifying conservation needs and supporting conservation planning from the field to
regional and national scales.
Between the CEAP surveys, cultivated cropland with moderately high and high runoff vulnerability increased by nearly 11
million acres. For cultivated cropland vulnerable to leaching, the only increase was in low vulnerability acres at nearly 12.5
million acres although it remained the smallest rating category. Cultivated cropland with moderately high wind vulnerability
increased by 4 million acres, while the rest of the rating categories declined.
Across the three vulnerability indexes, wind and runoff vulnerability have a similar distribution of acres among the rating
categories, with most acres having low vulnerability and least acres having high vulnerability. The distribution for leaching
vulnerability is nearly the opposite with most acres having a moderate or high rating. In CEAP II, nearly 30 percent of cultivated
cropland had high vulnerability to leaching as compared to 11 percent for runoff vulnerability and 1 percent for wind
vulnerability.
Cultivated Cropland by Soil Vulnerability Index Type and Rating, CEAP I and CEAP II

Table 4. Highly Erodible Cropland by Treatment Group, CEAP I and CEAP II
CEAP I
Treatment Group
Structural Practices, Conservation Tillage,
or Both
Structural Practices plus Conservation
Tillage
Conservation Tillage Only
Structural Practices Only
No Structural Practice(s) or Conservation
Tillage
National

Acres
(1000s)

CEAP II

CEAP II - CEAP I
Percent Acres
Percent HEL Relative to
CEAP I

Percent HEL

Acres
(1000s)

Percent
HEL

Acres
(1000s)

57,262

73

72,985

85

15,722

12

27

21,971

28

35,862

42

13,891

14

63

21,164
14,127

27
18

27,926
9,197

33
11

6,762
-4,930

6
-7

32
-35

21,155

27

12,800

15

-8,355

-12

-39

78,417

100

85,785

100

7,367

9

Conservation Practices on Cultivated Cropland
Figure 8. HEL Cultivated Cropland by Treatment Group and Region, CEAP I and CEAP II

19

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Conservation Effects Assessment Project

Cropland Vulnerable to Runoff—On the cultivated cropland most vulnerable to runoff (high
and moderately high SVI runoff categories), adoption of structural practices plus conservation tillage
increased by a combined 20.8 million acres between the CEAP surveys (table 5; appendix 2, table A-8).
By CEAP II, the combined practices on high and moderately high vulnerability acres increased by 81 and
74 percent, respectively (fig. 9). Use of conservation tillage alone increased by a small amount, about 1.3
million acres. Adoption of structural practices alone declined by 4.4 million acres.
Table 5. Cultivated Cropland with High and Moderately High Runoff (SVI) Ratings by Treatment Group,
CEAP I and CEAP II
CEAP I
Treatment Group
Structural Practices, Conservation
Tillage, or Both
High
Moderately High
Structural Practices plus Conservation
Tillage
High
Moderately High
Conservation Tillage Only
High
Moderately High
Structural Practices Only
High
Moderately High
No Structural Practices or
Conservation Tillage
High
Moderately High
National
High
Moderately High

CEAP II

CEAP II - CEAP I
Percent of Acres
Percent
Relative to
CEAP I

Acres
(1,000s)

Percent

Acres
(1,000s)

Percent

Acres
(1,000s)

23,453
42,250

86
79

31,340
52,114

93
90

7,887
9,864

7
11

34
23

11,605
15,497

43
29

20,974
26,898

63
46

9,370
11,401

20
17

81
74

6,706
16,268

25
30

6,877
17,436

21
30

171
1,169

-4
0

3
7

5,143
10,485

19
20

3,489
7,779

10
13

-1,654
-2,706

-9
-6

-32
-26

3,692
11,471

14
21

2,192
6,051

7
10

-1,500
-5,420

-7
-11

-41
-47

27,145
53,721

9
17

33,532
58,165

11
18

6,387
4,444

2
1

24
8

Figure 9. Cultivated Cropland with High and Moderately High SVI Runoff Rating by Treatment Group,
CEAP I and CEAP II

Conservation Practices on Cultivated Cropland

21

Cultivated Cropland with No Structural Practices or Conservation Tillage
As of CEAP II, some 61.1 million acres (19 percent) of cultivated cropland had neither structural
practices nor conservation tillage in place, down from 100.7 million acres (39 percent) in CEAP
I (fig. 10). Four regions (North Central and Midwest, Southern and Central Plains, Northern
Plains, and Lower Mississippi and Texas Gulf Coast) accounted for 74 percent of the cultivated
cropland without structural practices or conservation tillage.
Figure 10. Cultivated Cropland with No Structural Practices or Conservation Tillage by Region, CEAP I and
CEAP II

Conservation needs may be low on the acres without structural practices or conservation tillage,
or addressed through other measures (such as rotations or cover crops). However, treatment may
be particularly important on untreated acres highly vulnerable to erosion and/or runoff, or where
high rainfall intensifies potential soil losses. For example, of the total acreage lacking structural
practices or conservation tillage, 12.8 million acres were HEL and 8.2 million acres had high or
moderately high vulnerability to runoff (table 6).
Table 6. Cultivated Cropland with No Structural Practices or Conservation Tillage, CEAP I and CEAP II
CEAP I

CEAP II

CEAP II minus CEAP I

Percent
Change in
Acres
Relative to
CEAP I

Cultivated Cropland Group

Acres
(1,000s)

Percent
Acres

Acres
(1,000s)

Percent
Acres

Acres
(1,000s)

Percent
Acres

All Cultivated Cropland

100,651

32

61,148

19

-39,503

-13

-39

Highly Erodible Land
Percent of All Acres with No
Structural Practices or
Conservation Tillage
High and Moderately High
Runoff Vulnerability
Percent of All Acres with No
Structural Practices or
Conservation Tillage

21,155

27

12,800

15

-8,355

-12

-39

9

-6,920

-10

-46

21
15,163
15

21
19

8,243
13

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Conservation Effects Assessment Project

Conservation Crop Rotations and Cover Crops
Conservation crop rotations and cover crops have a common goal of reducing erosion through
covering or protecting the soil. A conservation crop rotation is a planned sequence of crops
grown on the same field over a period of time to achieve a conservation purpose, such as
reducing erosion or improving soil organic matter content. Cover crops are generally a grass,
small grain, or legume planted specifically to provide vegetative cover during the non-growing
season. Including cover crops, perennials, and winter annuals in a crop rotation provides yearround soil cover, and a variety of benefits such as promoting soil structure, taking up nutrients
that may otherwise be lost, and enhancing habitat for wildlife, including pollinators. Some
cropping systems and environments, however, are less conducive to the use of cover crops in
rotation, for example in arid or semiarid environments where additional water may be needed to
maintain productivity or where growing seasons are short. Technologies such as interseeding
before harvest can help to overcome challenges to late-season establishment of cover crops in
colder climates.
Conservation Crop Rotations
By CEAP II, nearly 70 percent of cultivated cropland acres had conservation crop rotations, up
from 66 percent in CEAP I, including 28 percent of all cultivated cropland acres having highbiomass conservation crop rotations (table 7; appendix 2, table A-9). For this report,
conservation crop rotations had to meet a biomass index score of 1.5 or higher; rotations with a
biomass index of 2.0 or higher were identified as high-biomass conservation crop rotations. 20 As
expected, high-biomass conservation crop rotations are concentrated in rotations with hay—84
percent of acres with hay in the rotation had high-biomass crop rotations—but only 16 percent of
acres with continuous row crop rotations were high-biomass conservation crop rotations.
About 31 percent of cultivated cropland acres (96.2 million acres) did not have a conservation
crop rotation in CEAP II. These acres, however, are not equally distributed among the four major
crop rotation groups. Only 11 percent of rotations that included hay were not in a conservation
crop rotation. In contrast, 51 percent of rotations with only close-grown crops were not in a
conservation crop rotation. While only 27 percent of rotations that included only continuous row
crops were not in a conservation crop rotation, that group accounted for over half of the total
acres without conservation crop rotations.
Of the 96 million acres without conservation crop rotations, 40 percent included an idle or fallow
year, which contributes little or no biomass to the rotation. These years were planned resting
periods to allow the soil to build up water or nutrient reserves or were idled because of external
conditions such as poor weather, natural disasters, or economic hardship. Ninety-eight percent
of rotations that included only close-grown crops and 69 percent of rotations that included hay
had an idle or fallow year in the rotation.

20

The biomass index assigns a score to each crop in a rotation based on the level of biomass produced (high, moderately high,
moderately low, low, and idle/fallow), and then averages these scores over the rotation to produce a single score.

Conservation Practices on Cultivated Cropland

23

Table 7. Cultivated Cropland by Crop Rotation Group, CEAP II
With Conservation Crop Rotations
Crop
Rotation
Group

Cultivated
Cropland
Acres
(1,000)

Percent

All*
Acres
(1,000s)

Percent

Without Conservation Crop
Rotations
With Idle or Fallow
High-Biomass**
All
in One or More
Rotation Years
Acres
Acres
Acres
Percent
Percent
Percent
(1,000s)
(1,000s)
(1,000s)

Hay With
20,787
7
18,459
89
17,503
84
Other Crops
Close-grown
15
23,077
49
20,287
43
Crops, No Hay 47,289
or Row Crops
Row and
21
44,689
68
19,650
30
Close-grown 65,719
Crops, No Hay
Continuous
181,509
58
132,865
73
29,223
16
Row Crops
All Cultivated
315,303
100
219,136
70
86,708
28
Cropland
* Acres with a crop rotation biomass index score greater than or equal to 1.5.
** Acres with a crop rotation biomass index score greater than or equal to 2.0.

2,328

11

1,599

69

24,212

51

23,631

98

21,030

32

8,517

41

48,644

27

4,183

9

96,167

31

37,986

40

All production regions except for the Northwest, South Central, and Southern and Central Plains
experienced an increase in conservation crop rotations between the CEAP surveys (fig. 11).
Specifically:
● Use of high biomass conservation crop rotations increased in all but four regions—Northern
Plains, Northwest, South Central, and Southern and Central Plains.
● Four regions—North Central and Midwest, Northeast, East Central, and South Central—
exceeded the national average of nearly 70 percent of cultivated cropland acres in conservation
crop rotations. The latter three also had 40 percent or more of their cultivated cropland in highbiomass conservation crop rotations.
● Three regions—California Coastal, Northern Plains, and Southern and Central Plains—were
below the CEAP II national average but still had more than half of their regional cultivated
cropland in conservation crop rotations.
● Half or fewer of the cultivated cropland acres in four regions—Atlantic and Gulf Coastal Plains,
Southwest, Lower Mississippi and Texas Gulf Coast, and Northwest—were in conservation crop
rotations.

Conservation crop rotations used in combination with conservation tillage can provide even
better protection against runoff and soil loss. Nearly half of all cultivated cropland acres have
combinations of conservation tillage and conservation crop rotations and another 21 percent have
conservation crop rotations but are conventionally tilled (fig 12).
Continuous row crops accounted for most cultivated cropland acres and most acres with
conservation crop rotations and conservation tillage (55 percent). Cultivated cropland with
continuous close-grown crops had the lowest percent of acres with conservation crop rotations
and conservation tillage (29 percent). The most common close-grown crop rotations were corn
and wheat, soybean and wheat, corn and soybean and wheat, rice and soybean, and wheat and
sorghum. Not surprisingly, hay with other crops in rotation, while the smallest share of cultivated
cropland (7 percent), had most acres meeting the definition of conservation crop rotation (88
percent) (table 8).

24

Conservation Effects Assessment Project

Figure 11. Percent of Cultivated Cropland with Conservation Crop Rotations by Biomass Index (BI) Level
and Region, CEAP I and CEAP II

Figure 12. Cultivated Cropland by Combinations of Conservation Crop Rotations and Tillage, CEAP II

Table 8. Cultivated Cropland by Crop Rotation Group and Tillage Group, CEAP II

Crop Rotation Group

Hay with other crops
Continuous Close-grown
crops, no hay or row crops
Row and close-grown crops,
no hay
Continuous Row crops,
no close-grown crops or hay
National

Cultivated
Cropland

Tillage Group
Conventional Tillage
Reduced Tillage
Continuous No-Till
Conservation Crop Rotation Status
With
Without
With
Without
With
Without

Acres
(1,000s)
20,787

45.3

3.9

22.6

2.6

20.8

4.8

47,289

19.6

17.1

12.7

11.5

16.5

22.7

65,719

22.4

11.9

18.7

8.8

26.8

11.4

181,509

18.1

12.0

31.9

8.2

23.2

6.6

315,303

21.0

12.2

25.6

8.4

22.8

9.9

Percent Crop Rotation Group Acres

Conservation Practices on Cultivated Cropland

25

Cover Crops
Between CEAP I and CEAP II, farmers’ use of cover crops increased from slightly over 2
million acres to nearly 19 million acres, yet cover crops were still used on only about 6 percent
of total cultivated cropland in CEAP II. Cover crop adoption between the two surveys was highly
concentrated in three regions—Atlantic and Gulf Coastal Plains, North Central and Midwest, and
Northern Plains—where 70 percent of the increase occurred (fig. 13).
Cover crops were more prevalent among continuous row crop rotations, which accounted for 58
percent of cultivated cropland acres but 68 percent of the acres with cover crops in one or more
years of the rotation (table 9). In CEAP II, about 7 percent of continuous row crop acres included
cover crops.
Nearly all acres with cover crops—94 percent—also had conservation crop rotations, in part due
to the biomass contribution of the cover crops (table 10). About 84 percent of the acres with
cover crops had high-biomass conservation crop rotations, which included high-biomass crops
such as hay (other than small-grain hay), grasses, grass seed, and wild rice. About 1.1 million
acres that included cover crops in the rotation did not meet the biomass index threshold (i.e.,
biomass index of 1.5 or greater) to be designated as a conservation crop rotation.
Figure 13. Cultivated Cropland with Cover Crops, CEAP I and CEAP II

Table 9. Use of Cover Crops in Major Crop Rotation Groups, CEAP II
Crop Rotation Group
National

Cultivated
Cropland

Cover
Crops

Acres (1,000s)
315,303
18,900
20,787
1,409

Average Crop
Years with
Cover Crops*

Group Acres Group Share
with Cover of All Cover
Crops
Crops
Percent
6.0
100.0
6.8
7.5

56
Hay with Other Crops
44
Continuous Close-grown Crops, No Hay or
47,289
654
45
1.4
3.5
Row Crops
Row and Close-grown Crops, No Hay
65,719
3,996
47
6.1
21.1
Continuous Row Crops
181,509
12,840
61
7.0
67.9
* For sample points with rotations that included cover crops, the number of years in the rotation that had cover crops was
divided by the number of years in the full rotation. This proportion was then averaged over all the sample points with cover crops
and reported here as an average percentage.

26

Conservation Effects Assessment Project

Table 10. Cover Crops and Conservation Crop Rotations by Major Crop Rotation Group, CEAP II
Crop Rotation Group
National
Hay with Other Crops
Close-grown Crops, No Hay or Row Crops
Row and Close-grown Crops, No Hay
Row crops, No Close-grown Crops or Hay

Cultivated
Cropland with
Cover Crops

Cover Crop Acres
with Conservation
Crop Rotation

Acres (1,000s)
18,900
1,409
654
3,996
12,840

Percent
94.2
94.0
83.6
93.1
95.1

Cover Crop Acres with
High-Biomass
Conservation Crop
Rotation
Percent
83.8
90.7
77.0
78.9
84.9

About 6 percent of cultivated cropland acres included cover crops in one or more years of the
rotation in CEAP II. Cover crop use in the Northeast, Atlantic and Gulf Coastal Plains, and East
Central regions was substantially higher than the national average, accounting for 30 percent of
acres with cover crops in the rotation while accounting for only 10 percent of all cultivated
cropland acres (table 11).
Table 11. Cover Crop Use by Region, CEAP II
Production Region
National
Atlantic and Gulf Coastal Plains
California Coastal
East Central
Lower Mississippi and Texas Gulf
Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest

Cultivated
Cropland

Cover
Crops

Acres (1,000s)
315,303
18,900
13,825
2,587
3,913
169
10,166
1,511

Regional
Cultivated
Cropland

Regional Share
of All Cover
Crop Acres

100
4
1
3

Regional
Acres with
Cover Crops
Percent
6
19
4
15

100
14
1
8

20,916

506

7

2

3

123,296
7,597
51,130
13,438
5,107
62,732
3,183

7,815
1,611
1,995
227
170
2,231
77

39
2
16
4
2
20
1

6
21
4
2
3
4
2

41
9
11
1
1
12
0

Cover crop use in the North Central and Midwest region was close to the national average with
about 6.3 percent of cultivated cropland with cover crops in rotation, although that region
accounted for 41 percent of all cultivated cropland acres with cover crops nationally (fig 14). All
other regions were below the national average. Humid and subhumid production regions
generally have adequate precipitation and infiltration to replenish soil water used by cover crops.
The low use of cover crops in certain production regions (California Coastal, Lower Mississippi
and Texas Gulf Coast, Northwest, South Central, and Southwest) reflects the arid or semi-arid
conditions or water intensive production systems (e.g., rice) where additional water is needed to
maintain productivity.21, 22, 23
Eash, L., Berrada, A.F., Russell, K. and Fonte, S.J., 2021. Cover Crop Impacts on Water Dynamics and Yields in Dryland Wheat
Systems on the Colorado Plateau. Agronomy, 11(6), p.1102.
22 Nielsen, D.C., Lyon, D.J., Hergert, G.W., Higgins, R.K., Calderón, F.J. and Vigil, M.F., 2015. Cover crop mixtures do not use
water differently than single-species plantings. Agronomy Journal, 107(3), pp.1025-1038.
23 Unger, P.W. and Vigil, M.F., 1998. Cover crop effects on soil water relationships. Journal of Soil and Water Conservation,
53(3), pp. 200-206.
21

Conservation Practices on Cultivated Cropland

27

Figure 14. Cover Crop Use on Cultivated Cropland by Region, CEAP II

Irrigation
About 49.7 million cropland acres were irrigated by CEAP II, an increase of 4.9 million acres
(11 percent) over the CEAP I level (table 12). Irrigated acres are concentrated where the practice
is either required for production because of low precipitation, where it enables more profitable
crops, where water supplies are available, and where producers view the capital expense as a
sound production investment (fig. 15). Over two-thirds of irrigated acreage is in three regions—
Southern and Central Plains (34 percent), Lower Mississippi and Texas Gulf Coast (23 percent),
and North Central and Midwest (10 percent).
Table 12. Total Cropland, Irrigated Cropland, and Change in Irrigated Acres, CEAP I and CEAP II,
Nationally and by Region
CEAP I
Total
Irrigated
Geographic Area
Cropland
Cropland Percent
Irrigated
Acres
Acres
(1,000s)
(1,000s)
National
313,065
44,802
14
Southern and Central Plains
64,337
15,564
24
Lower Mississippi and Texas Gulf Coast
21,816
8,970
41
North Central and Midwest
120,134
3,857
3
Northwest
14,010
5,156
37
California Coastal
4,447
3,775
85
Atlantic and Gulf Coastal Plains
14,395
2,127
15
Southwest
2,870
2,366
82
Northern Plains
48,420
1,776
4
South Central
6,135
930
15
East Central
9,312
195
2
Northeast
7,190
85
1
* Regions in table sorted by declining CEAP II irrigated cropland acres.

Total
Cropland
Acres
(1,000s)
315,303
62,732
20,916
123,296
13,438
3,913
13,825
3,183
51,130
5,107
10,166
7,597

CEAP II
Irrigated
Cropland
Acres
(1,000s)
49,711
16,778
11,651
5,218
4,554
3,193
2,902
2,571
1,762
672
233
177

Change in Acres
Percent
Irrigated
16
27
56
4
34
82
21
81
3
13
2
2

(1,000s)
4,909
1,214
2,681
1,362
-603
-583
775
205
-14
-259
38
92

Percent
11
8
30
35
-12
-15
36
9
-1
-28
19
109

28

Conservation Effects Assessment Project

Figure 15. Acres of Irrigation on Cropland and Pastureland, 2017

Change in irrigated cropland between the CEAP surveys varied by region. There were increases
in seven regions but declines in four—the Northern Plains, South Central, California Coastal,
and Northwest. The greatest increase in irrigated cropland occurred in the Lower Mississippi and
Texas Gulf Coast with over 2.6 million additional irrigated acres (fig. 16). Although the
Northeast more than doubled irrigated acres between the CEAP surveys, it still has the fewest
total irrigated acres (table 12, above). The Atlantic and Gulf Coastal Plains, North Central and
Midwest, and Lower Mississippi and Texas Gulf Coast all increased irrigated area by 30 percent
or more from CEAP I levels.
Irrigation intensity is greatest in areas with low rainfall in the growing season, or where crops
require either additional water or water at a different time than normal precipitation. Irrigation is
employed on 82 percent of the cropland acres in the California Coastal region and on 81 percent
in the Southwest region, both characterized by low rainfall. In the more humid Lower
Mississippi and Texas Gulf Coast region, about 56 percent of the cropland is irrigated due to the
crops grown (rice is 100-percent irrigated), low soil water holding capacity, and precipitation
timing (table 12, above).

Conservation Practices on Cultivated Cropland

29

Figure 16. Change in Irrigated Cropland by Region, CEAP I to CEAP II

Note: Number at the end of each bar reflects the percent change in irrigated acreage relative to CEAP I levels.

Water Sources
In CEAP II, about 77 percent of irrigated cropland acres were served by groundwater, 21 percent
by surface water, and the remaining 2 percent by the combined sources (fig. 17). Use of
groundwater increased by about 6 percent (over 6 million acres), and use of surface water and
combined sources declined by 4 percent (more than 900,000 acres) and 1 percent (400,000
acres), respectively, relative to CEAP I levels. While surface water sources are more susceptible
to drought shortages, groundwater sources may be challenged by aquifer declines and exhaustion
of the resource.
Figure 17. Sources of Water for Irrigated Cropland, CEAP I and CEAP II

30

Conservation Effects Assessment Project

Surface water was the predominant irrigation water source in the western United States
(California Coastal, Northwest, and Southwest regions) and the East Central region, while
groundwater sources dominated in the remaining seven regions. However, groundwater is an
important and growing share of irrigation water supplies in the western regions. In the Southwest
region, groundwater-supplied acres increased by 20 percentage points (18 points from
groundwater and 2 points from combined sources)—from 24 percent in CEAP I to 42 percent by
CEAP II. In the Northwest region groundwater-supplied acres increased by 14 percentage points
while surface water acres decreased by a similar share. The California Coastal region’s
dependence on groundwater grew by 11 percentage points, while surface-only irrigated acres
decreased by only 1 percentage point (fig. 18)
Application Methods
In the period between CEAP I and CEAP II there was a national shift toward irrigation pressure
application systems, increasing 12 percentage points to 66 percent, and accounting for 8.7
million acres. Most regions primarily use pressure systems, while three regions (California
Coastal, South Central, and Lower Mississippi and Texas Gulf Coast) primarily use gravity
application methods. The East Central and Northeast regions depend wholly on pressure-based
systems (fig. 19).
Between the two survey periods, every region except the South Central maintained or increased
the share of irrigated cropland served by pressure systems. Use of pressure systems in the
Atlantic and Gulf Coastal Plains region increased by 25 percentage points (1.3 million acres), in
the Northwest and Southwest regions by 19 percentage points (over 400,000 and 500,000 acres,
respectively), and in the California Coastal and Southern and Central Plains regions by 15
percentage points (400,000 acres and 3.4 million acres, respectively). The South Central region’s
decline in pressure systems was consistent with the overall irrigated cropland decline of 259,000
acres in the region.
Nationally, low-pressure center pivot systems were the most prevalent in CEAP I and CEAP II,
and the share of irrigated cropland area served by these systems increased from 30 percent to 37
percent (13.4 to 18.6 million acres) (fig. 20). Center pivot technology in its various forms (lowpressure spray, impact sprinklers, and on- or near-ground emitters) increased from 47 percent of
irrigated cropland acres in CEAP I to 54 percent of cropland acres in CEAP II. The most used
gravity irrigation technology was poly-pipe, which increased to 13 percent of cropped acres in
CEAP II, up from 8 percent in CEAP I. Poly-pipe systems are extensively used in the Lower
Mississippi and Texas Gulf Coast and South Central regions. The only other gravity distribution
system with a double-digit share was an open discharge system from a well, pipeline, gate, or
valve with 10 percent of acres in CEAP II, down from 12 percent in CEAP I.
The regions that rely on pressure systems were increasingly using low-pressure spray center
pivots (fig. 21). In the East Central region, the most common irrigation technology in CEAP II
was hand-move sprinklers, which are not suitable for all crops. In the Northeast the most
common irrigation technology in CEAP II was big gun sprinklers, which are relatively low-cost
and are versatile across crops and terrain, but not as efficient as other pressure options.

Conservation Practices on Cultivated Cropland

Figure 18. Water Sources for Irrigated Cropland, Nationally and by Region, CEAP I and CEAP II

Figure 19. Irrigation Water Application Technology, Nationally and by Region, CEAP I and CEAP II

31

32

Conservation Effects Assessment Project

Figure 20. National Irrigation Water Application Systems on Cropland, CEAP I and CEAP II

* Low-Flow irrigation includes drip, trickle, and micro-sprinklers
**Other pressure includes side roll or wheel move, solid or permanent and big gun each with less than 2 percent of acres.
*** Open discharge is water flowing from a pipe, well, gate, or valve with no flow control.
****Other gravity includes subirrigation, portal system from a lined ditch, and improved gated pipe (surge flow or cablegation)
each with no more than 1 percent of acres.

Figure 21. Most Prevalent Regional Irrigation Water Application Systems on Cropland, CEAP I and CEAP
II

Conservation Practices on Cultivated Cropland

33

Application Efficiency
Irrigation water efficiency is a measure of water inputs to production outputs and was estimated
by calculating the Virtual Irrigation System Efficiency (VISE).24 The higher the VISE score, the
more efficient the system. VISE is not a measured efficiency but is calculated from information
obtained from a farmer survey on the physical distribution system, water source and conveyance
method, and irrigator decisions on timing and amounts. Soil properties based on the field soil
type from National Resources Inventory (NRI) points were also considered in the efficiency
score.
The average VISE score increased from 62 percent to 76 percent from CEAP I to CEAP II. The
14-point (23-percent) improvement implies that irrigators needing to provide 12 inches of water
to meet plant consumptive needs could reduce water application by 3.6 inches or almost 20
percent. This potential reduction in water applied translates directly into reduced pumping costs
for groundwater and reduced surface water diversions to maintain the same acreage.
All regions increased their irrigation efficiencies between CEAP I and CEAP II (fig. 22). In
CEAP II, the Southern and Central Plains and North Central and Midwest regions had the
highest efficiency scores at 80 percent and the Northeast had the lowest at 70 percent. The
Figure 22. VISE Efficiency Scores in CEAP I and CEAP II and Most Prevalent Technology in CEAP II, by
Region

Because the calculation process considers the delivery loss inherent in 19 water application technologies, runoff from the
field (technology and management based) and deep percolation (soils, technology and management based), there can be a
wide range of estimated VISE efficiency scores within an individual application technology as well as across technologies.

24

34

Conservation Effects Assessment Project

greatest gain in average score was in the East Central region from 55 percent in CEAP I to 77
percent in CEAP II, in large part due to the shift to hand-move sprinklers. The smallest
efficiency gains were the 8-percent increase in the Southern and Central Plains (low-pressure
center pivot sprinklers in both periods) and the 10-percent increase in the Northeast (big gun
sprinkler in both periods). The four regions with the highest estimated efficiency scores all relied
on low-pressure center pivots as the most prevalent irrigation application technology.
Nationally, there was about a 30-percent decline in acres with lower VISE scores and about a 40
percent increase in acres with higher VISE scores. This pattern was repeated in all production
regions (fig. 23). The shift may have been technology based or management based, or by adding
irrigated acres on better suited soils, or more likely a combination of all efficiency drivers.
Figure 23. Irrigated Acreage Distribution of VISE Efficiencies by VISE Grouping and Region, CEAP I and
CEAP II

Application Amount
Total irrigation water applications on cropland declined nationally and in most regions despite
the increase in irrigated acres. In CEAP I the average irrigation water application was 19.2
inches per acre, declining to 15.6 inches per acre in CEAP II (table 13). Total irrigation water
applications declined 10 percent (from 71.7 million acre-feet to 64.6 million acre-feet), even
though irrigated acres increased by 11 percent (4.9 million acres).
Nationally, the average per-acre decline in water application was about 3.6 inches with the
Lower Mississippi and Texas Gulf Coast region having the greatest decline at 5.5 inches. Only
one region, the Northeast, increased average water application per acre and total water applied

Conservation Practices on Cultivated Cropland

35

from CEAP I to CEAP II; three regions (Southwest, North Central and Midwest, and Atlantic
and Gulf Coastal Plains), despite having less water applied per acre, gained enough irrigated
acres to increase total water applications as well. Two regions, Lower Mississippi and Texas
Gulf Coast and Atlantic and Gulf Coastal Plains, recorded more than 20-percent declines in peracre water applications. In the South Central region, total water applications declined by over 30
percent, due in large part to the nearly 30-percent decline in cultivated cropland acres.
Table 13. Irrigation Water Applications, Total Water Applied, and Change in Water Applications, CEAP I to
CEAP II, by Region
CEAP I
Geographic Area

Average
Water
Applied
Inches/
acre
19.2

Total
Water
Applied
1000
acre-feet
71,683

CEAP II
Average
Water
Applied
Inches/
acre
15.6

Total
Water
Applied
1000
acre-feet
64,624

National
Region*
Southern & Central
15.7
20,363
14
19,575
Plains
Lower Mississippi &
17,193
16,991
23
17.5
Texas Gulf Coast
12,773
9,631
California Coastal
40.6
36.2
9,325
6,907
Northwest
21.7
18.2
5,521
5,548
Southwest
28
25.9
North Central &
1,993
2,218
6.2
5.1
Midwest
1,924
1,542
Northern Plains
13
10.5
1,589
1,091
South Central
20.5
19.5
Atlantic & Gulf
940
1,016
5.3
4.2
Coastal Plains
East Central
4.4
72
3.7
72
20
52
Northeast
2.9
3.5
* Regions in table sorted by declining CEAP II total water application amounts.

Change CEAP I
to CEAP II
Average
Total
Water
Water
Applied
Applied
Inches/
1000
acre
acre-feet
-7,060
-3.6

Change from CEAP I
Average
Water
Applied

Total
Water
Applied

Percent

Percent

-19

-10

-1.7

-788

-11

-4

-5.5

-202

-24

-2

-4.4
-3.5
-2.1

-3,141
-2,418
28

-11
-16
-8

-25
-26
0

-1.1

225

-18

10

-2.5
-1

-382
-498

-19
-5

-21
-31

-1.1

76

-21

11

-0.7
0.6

0
31

-16
21

0
900

Nutrient Management
Nitrogen is essential for protein formation, and plants take up more of this nutrient than any
other. The second most required nutrient is phosphorus, essential for plants to use and store
energy. Some crops, such as corn, have high nitrogen demands, while others such as soybeans
meet their nitrogen demand through a process called biological nitrogen fixation.
Practices to manage nutrients include application rate, timing, method, and form or source. There
are many ways to combine these four components to maintain or enhance production and
minimize potential losses. Climate, soil, cropping system, and tillage influence the options
available to farmers (box 4).

36

Conservation Effects Assessment Project

Box 4. Advances in Nutrient Technology
Precision guidance systems allow for improved placement of nutrients and the ability to apply nutrients to actively growing
crops. Together, variable-rate technologies in combination with enhanced-efficiency fertilizers (EEFs) can better match nutrient
application rates to the differing needs of unique soil types within a field and their production potential, and reduce the impact
of early application by extending the release of nutrients and, for some forms, by reducing volatile losses.
Use of variable rate technology more than quadrupled between CEAP I and CEAP II. Gains were concentrated in the North
Central and Midwest region, accounting for 55 percent of the total increase. Only two regions, South Central and Southwest,
experienced small declines over the time period.
Variable Rate Technology Adoption by Region, CEAP I and CEAP II
CEAP I
Geographic Scope
Acres
Percent
(1,000s)
Acres
National
12,567
4
Region
Atlantic and Gulf Coastal Plains
515
4
California Coastal
192
5
East Central
277
3
Lower Mississippi and Texas Gulf Coast
493
3
North Central and Midwest
6,023
5
Northeast
160
2
Northern Plains
1,849
4
Northwest
1,022
8
South Central
335
6
Southern and Central Plains
1,597
3
Southwest
104
4

CEAP II
Acres
Percent
(1,000s)
Acres
51,215
16

CEAP II minus CEAP I
Acres
Percent
(1,000s)
Acres
38,648
12

2,632
296
1,038
3,885
27,632
426
7,575
2,302
330
5,034
66

2,117
104
761
3,392
21,610
266
5,726
1,280
-5
3,437
-38

19
8
10
19
22
6
15
17
6
8
2

15
3
7
16
17
3
11
10
1
5
-1

Between the survey periods, use of EEFs increased by over 6-fold and were in use on over one-fourth of all cultivated cropland
by CEAP II. All regions showed gains in EEF use, with the North Central and Midwest accounting for 55 percent of the total
increase.
Enhanced-Efficiency Fertilizer Adoption by Region, CEAP I and CEAP II
CEAP I
Geographic Scope
Acres
Percent
(1,000s)
Acres
National
11,734
4
Region
Atlantic and Gulf Coastal Plains
327
2
California Coastal
130
4
East Central
353
4
Lower Mississippi and Texas Gulf Coast
983
6
North Central and Midwest
8,301
7
Northeast
353
5
Northern Plains
355
1
Northwest
154
1
South Central
118
2
Southern and Central Plains
642
1
Southwest
17
1

CEAP II
Acres
Percent
(1,000s)
Acres
74,146
26

CEAP II minus CEAP I
Acres
Percent
(1,000s)
Acres
64,412
22

2,356
352
2,215
4,629
44,139
2,754
8,334
1,871
741
6,505
249

2,029
222
1,862
3,646
35,838
2,401
7,978
1,717
623
5,863
232

19
10
23
28
38
39
17
15
16
12
9

17
7
19
23
31
34
16
13
14
11
8

Conservation Practices on Cultivated Cropland

37

Rate
Nutrient application rates vary by crop and take into consideration all sources of essential
nutrients. Cultivated cropland acres on which a soil test was taken within the last 5 years
increased slightly over the decade, from 56 percent to 60 percent. Where manure was applied,
soil testing rates were at 77 percent (box 5). However, nutrient application rates on manured
acres still were substantially higher than rates on acres receiving only commercial fertilizers,
perhaps related to a lag in manure testing.
Nationally, application rates of nitrogen and phosphorus from all sources increased between the
CEAP surveys (table 14). Average nitrogen rates increased by 7 percent, from 73 to 78.5 lbs/a/y.
The largest increase occurred in the Northern Plains region at 16.6 lbs/a/y, over three times the
national average increase. The North Central and Midwest was the only other region with a rate
increase above the national average. The expansion of corn production in these two regions
drove the need for more nitrogen (fig. 24).
Phosphorus application rates increased by 15 percent, from 16.2 to 18.6 lbs/a/y. Five regions had
rate increases above the national average increase of 2.4 lbs/a/y. The largest rate increase
occurred in the Northern Plains region at 4.5 lbs/a/y.
Table 14. Nutrients Applied on Cultivated Cropland, CEAP I and CEAP II
Nutrient
Nitrogen
Phosphorus

Acres
Receiving
(1,000s)
294,384
268,472

CEAP I
Tons
Applied
(1,000s)
11,433
2,538

Rate
(lbs/a/y)
73
16.2

Acres
Receiving
(1,000s)
294,069
278,859

CEAP II
Tons
Applied
(1,000s)
12,263
2,930

Rate
(lbs/a/y)
78.5
18.6

CEAP II minus CEAP I
Acres
Tons
Rate
Receiving
Applied
(lbs/a/y)
(1,000s)
(1,000s)
-315
830
5.2
10,387
392
2.4

Figure 24. Change in Nitrogen and Phosphorus Application Rates by Region, CEAP II minus CEAP I

38

Conservation Effects Assessment Project

Box 5. Soil Testing for Nutrient Management
Testing soils for nitrate nitrogen, phosphorus, organic matter, potassium, pH, and soluble salts content provides essential
information for developing a sound nutrient management strategy and determining appropriate nutrient application rates to
promote healthy plant growth and minimize potential for nutrient losses. Between the CEAP surveys, the share of cultivated
cropland acres having had a soil test within the previous 5 years increased from 56 to 60 percent.
Soil Testing on Cultivated Cropland, CEAP I and CEAP II
Cultivated Cropland with Soil Test within
Previous 5 Years by Nutrient Type
Cultivated Cropland Acres with Soil Test
Commercial N and P and/or Manure
Commercial N and P Only
Manure with/without Commercial N and P
No Commercial N or P Applied

CEAP I
Acres
Acres
(1,000s)
Percent
174,086
56
171,626
57
154,143
56
17,483
65
2,460
20

CEAP II
Acres
Acres
(1,000s) Percent
189,222
60
187,332
62
163,679
60
23,653
77
1,890
14

CEAP II minus CEAP I
Acres
Acres
(1,000s)
Percent
15,136
4
15,706
5
9,536
4
6,169
12
-570
-5

Cultivated cropland acres receiving manure (with or without commercial fertilizers) were tested more frequently than those
receiving commercial fertilizers only. In CEAP II, 77 percent of manured acres had recent soil tests, compared to 60 percent of
acres receiving commercial fertilizer only.
Between CEAP I and CEAP II, soil testing rates on acres receiving only commercial fertilizer increased by 4 percentage points,
from 56 percent in CEAP I to 60 percent in CEAP II. In contrast, soil testing on acres receiving manure increased by 12
percentage points, suggesting growing awareness of the importance of soil testing when using manure nutrients. However, the
use of manure testing to understand manure nutrient content lagged at only 48 percent in CEAP II. Consequently, over half the
acres receiving manure lacked information to establish appropriate application rates to ensure meeting crop needs, while
minimizing potential for losses or soil phosphorus accumulation.
Most regions increased the number of cultivated cropland acres with recent soil tests in CEAP II. In the California Coastal,
Northeast, and Northwest regions, soil testing increased by 13 percentage points or more. The South Central region was alone
in experiencing a reduction in acres with a recent soil test. Six regions had soil testing rates higher than the national average (60
percent). The South Central, Southern and Central Plains, Southwest, and Lower Mississippi and Texas Gulf Coast were the only
regions with soil testing rates below 50 percent of their regional cultivated cropland acres.
Soil Testing* on Cultivated Cropland by Region, CEAP I and CEAP II
CEAP I
Geographic Scope
Acres
Acres
(1,000s)
Percent
National
174,086
56
Region
Atlantic and Gulf Coastal Plains
11,262
78
California Coastal
1,768
40
East Central
5,698
61
Lower Mississippi and Texas Gulf Coast
9,548
44
North Central and Midwest
78,583
65
Northeast
4,097
57
Northern Plains
26,106
54
Northwest
7,748
55
South Central
2,252
37
Southern and Central Plains
26,052
40
Southwest
972
34
* Soil test within the previous 5 years

CEAP II
Acres
Acres
(1,000s)
Percent
189,222
60
10,793
2,127
6,258
9,476
85,025
5,308
31,276
9,636
1,638
26,353
1,332

78
54
62
45
69
70
61
72
32
42
42

CEAP II minus CEAP I
Acres
Acres
(1,000s)
Percent
15,136
4
-469
359
560
-71
6,442
1,211
5,170
1,888
-614
301
360

<1
15
0
2
4
13
7
16
-5
2
8

Conservation Practices on Cultivated Cropland

39

Method
Nutrients are applied to fields in a variety of ways but can be divided between those that place
the nutrient on the soil surface and those that incorporate nutrients beneath the soil surface.
Knifing, injection, and other incorporation methods place nutrients in the root zone for growing
plants, which also reduces potential for nutrient loss via wind and rain. There are many reasons
that drive decisions on application method from the nutrient source (some manures are more
difficult to incorporate) to application timing (incorporating nutrients into a growing crop is
more difficult).
Between the two CEAP surveys, there was a clear trend away from nutrient incorporation on
cultivated cropland, and as a result increased opportunity for losses from fields. By CEAP II, 50
percent of nitrogen applied and 20 percent of phosphorus applied were not incorporated (table
15; appendix 2, tables A-10 and A-11). The acreage on which all nutrient applications were
incorporated declined for nitrogen (by 29 percent) and phosphorus (by 24 percent). In contrast,
the acres where none of the nutrient applications were incorporated increased for nitrogen (by 41
percent) and phosphorus (by 46 percent).
All regions experienced a similar pattern of a decrease in all applications incorporated and an
increase in applications with no incorporation for both nutrients (fig. 25). Three regions—North
Central and Midwest, Northern Plains, and Southern and Central Plains—accounted for 90
percent of the change in tons of nitrogen applied without incorporation. The North Central and
Midwest region alone accounted for nearly half of the change in tons of phosphorus applied
without incorporation.
Table 15. Cultivated Cropland with Nutrients Applied by Type and Incorporation, CEAP I and CEAP II
CEAP I
Incorporation Status

Acres
(1,000s)

Application Acres
All Incorporated
Some Incorporated
None Incorporated

294,384
152,265
101,346
40,773

Application Acres
All Incorporated
Some Incorporated
None Incorporated

268,472
133,376
99,392
35,704

Percent

Tons
(1,000s)

CEAP II
Percent

Acres
(1,000s)

Percent

Tons
(1,000s)

Percent

CEAP II minus CEAP I
Percent
Percent
Acres
Tons
Relative
Relative
(1,000s)
(1,000s)
to
to
CEAP I
CEAP I

Nitrogen
52
34
14

11,433
5,275
1,513
4,645

50
37
13

2,538
1,116
1,070
352

46
13
41

294,069
107,423
129,018
57,628

44
42
14

278,859
100,995
125,593
52,270

37
44
20

12,263
3,864
2,223
6,176

32
18
50

-315
-44,842
27,672
16,855

-29
27
41

830
-1,411
710
1,531

7
-27
47
33

2,930
923
1,418
589

32
48
20

10,387
-32,381
26,201
16,567

4
-24
26
46

393
-193
348
237

15
-17
33
67

Phosphorus
36
45
19

Timing
Nutrients may be applied before planting (pre-plant), at the time of planting (at-plant), or
following the emergence of the crop (post-plant). In general, nutrient uptake rates are highest
from early to mid-growing season, which is why at-plant and post-plant applications together
account for the largest share of applications. Post-plant applications occur when crops are
actively growing and have the greatest nutrient needs; however, incorporation is complicated by
the potential for plant damage. Pre-plant application avoids the challenge of applying fertilizer,
particularly manure, to a growing crop, but leaves nutrients exposed for a longer time before
uptake, increasing opportunities for losses.

40

Conservation Effects Assessment Project

Figure 25. Change in Incorporation Extent and Region, CEAP II minus CEAP I

Pre-plant (>21 days) applications that were not incorporated increased while incorporated
applications declined. By CEAP II, the increases in the unincorporated pre-plant load were
392,000 tons for nitrogen and 95,000 tons for phosphorus, while incorporated loads dropped by
172,000 tons for nitrogen and 46,000 tons for phosphorus.
Most nitrogen and phosphorus applications are at plant (application within 7 days of planting),
although there was a net decline in tons applied between the two CEAP surveys. Nitrogen
applied at plant and incorporated declined by 22 percent, while applications not incorporated
increased by 28 percent relative to CEAP I levels. Phosphorus applied at plant and incorporated
declined by 7 percent, and applications not incorporated increased by 22 percent relative to
CEAP I levels (fig. 26; appendix 2, tables A-12 and A-13).
The nutrients applied during the other three timing periods increased by nearly 1.5 million tons
of nitrogen and 372,000 tons of phosphorus. Most of the increase occurred post-plant and as
unincorporated applications of nitrogen and phosphorus, 61-percent and 169-percent increases
from CEAP I levels, respectively.

Conservation Practices on Cultivated Cropland

41

Figure 26. Total Applied Nutrients by Timing and Incorporation, CEAP I and CEAP II

Note: The increase in the unincorporated load relative to CEAP I levels is shown as a percent above the CEAP II values for each
application timing.

Technology advances, such as nitrogen inhibitors and precision guidance systems, increase
timing options; despite this, incorporation is still essential to reduce loss risk. Between the CEAP
survey periods, enhanced-efficiency fertilizers were used on an additional 64 million acres by
CEAP II or 26 percent of cultivated cropland (see also box 4, page 36). Farmers also increased
the use of variable rate technology (VRT), using it on an additional 38.6 million acres or 17
percent of all cultivated cropland by CEAP II.

Manure Application Trends
Between CEAP I and CEAP II, acres receiving manure nutrients increased substantially,
reflecting the continuing increase and consolidation in the sector. The significant increase in the
purchase of manure nutrients signaled a departure from viewing manure simply as a wastedisposal problem. While soil testing increased and manured acres had substantially higher testing
rates, increased application rates and load-to-loss disparities indicate continuing challenges.
Manure nutrients can be more mobile than commercial mineral nutrients as they may be less
dense and more soluble, although the fraction of manure nutrients in organic form may release

42

Conservation Effects Assessment Project

over time through mineralization. A combination of proper rates, timing, and application
methods is necessary to manage losses from all sources to meet defined threshold levels.
Cultivated cropland receiving manure increased by 14 percent to nearly 31 million acres in
CEAP II, roughly 10 percent of all cultivated cropland (table 16). Between CEAP I and CEAP II,
acres receiving only manure nutrients increased by 28 percent (908,000 acres) and acres
receiving manure and commercial fertilizer increased by 12 percent (2.8 million acres). In both
surveys, acres receiving manure had higher nitrogen and phosphorus application rates than those
receiving only commercial fertilizer—over 71 and 90 percent higher, respectively, in CEAP II.
Table 16. Average Annual Nutrient Application Rates—Manured and Commercial Only
Nutrient Source
Manure Acres
(with or without
Commercial)
Manure Only
Acres
Manure w/
Commercial
Commercial
Nitrogen without
Manure
Commercial
Phosphorus
without Manure

Cultivated Cropland
CEAP II
CEAP I CEAP II
minus
CEAP I
Acres (1,000s)

Nitrogen Application Rate
Phosphorus Application Rate
CEAP II
CEAP II
CEAP I CEAP II minus
CEAP I CEAP II
minus
CEAP I
CEAP I
Pounds/acre/year

27,013

30,727

3,713

136

140

5

39

38

-1

3,241

4,150

908

112

110

-2

42

40

-2

23,772

26,577

2,805

139

145

5

39

38

-1

267,371

263,343

-4,028

76

82

6

241,459

248,132

6,673

18

20

2

The top three regions for receiving manure were the North Central and Midwest at 16.3 million
acres, the Southern and Central Plains with 3.2 million acres, and the Northeast with 3.1 million
acres. While manured acres are a minor portion of the total acres in the North Central and
Midwest (13 percent) and Southern and Central Plains (5 percent) regions, they make up 41
percent of the cultivated cropland acres in the Northeast.
Because of higher application rates, manured acres received a disproportionate share of the total
nutrients applied in every region (fig. 27). Overall, the proportion of nitrogen losses equaled or
were below the applied load in 10 regions, while for phosphorus losses that was the case in only
five regions. In the North Central and Midwest region, the 13 percent of regional acres that
received manure accounted for 19 percent of the total applied nitrogen and 20 percent of the total
applied phosphorus, while nitrogen and phosphorus losses on these acres were 19 percent and 36
percent of the total regional losses, respectively. In the Northeast, the 41 percent of acres that
received manure accounted for 59 percent of total applied nitrogen and 62 percent of the total
applied phosphorus. While nitrogen losses were less than the applied load, they still made up
nearly half (47 percent) of the regional nitrogen losses; phosphorus losses at 68 percent exceed
the applied phosphorus load, making manure management one of the highest regional priorities.
The contrast in percent load and percent loss illustrates the regional challenges in managing
manure nutrients, particularly with respect to its commercial counterpart.

Conservation Practices on Cultivated Cropland

43

Figure 27. Nitrogen and Phosphorus Applied Load and Losses from Cultivated Cropland Receiving Manure
Nutrients, CEAP II

Acres receiving manure and commercial fertilizer have nutrient application rates nearly twice
that of acres receiving only commercial fertilizers, and almost a third higher than acres receiving
manure alone. In seven regions, commercial nitrogen accounts for 40 percent or more of the total
nitrogen applied on manured acres (fig. 28). Overall phosphorus application rates are lower, but
commercial phosphorus still accounts for 20 percent or more of the total phosphorus applied in
six regions. The use of manure testing to understand nutrient content was done on only 48
percent of the manured cropland in CEAP II; consequently, over half the acres receiving manure
lacked adequate information to establish appropriate application rates for crop needs, while
minimizing potential for losses or soil phosphorus accumulation. It is unclear why operators may
apply additional commercial fertilizer, which may not be necessary for crop production,
constitutes an additional production cost, and may increase potential loss risks. This suggests
there is a need to better understand manure nutrient content and availability for plant growth.
Between the CEAP surveys, winter application of manure declined, largely the portion that was
not incorporated, and reduced the amount of manure nutrients exposed to potential losses in that
season. Applications in the other three seasons—but particularly in spring and fall—increased
(fig. 29). Most of the total load is applied in spring and fall before and after the active growing
periods of most crops, when incorporation is critical to ensure that applied nutrients remain in
place.

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Conservation Effects Assessment Project

Figure 28. Nitrogen and Phosphorus Applied to Manured Acres by Source and Region, CEAP II

Figure 29. Seasonal Application of Manure Nutrients by Method, CEAP I and CEAP II

Conservation Practices on Cultivated Cropland

45

Spring is generally the wettest season, increasing the potential for nutrient losses. The total
spring load increased by 12 percent for nitrogen and 18 percent for phosphorus, and while the
incorporated applications increased, led by increases in dairy and swine manure injection, so also
did applications that were not incorporated. Fall applications also increased as did the
incorporated portion, particularly for nitrogen.
While the summer load and its unincorporated portion increased, applications are on actively
growing crops, which have lower loss potential even when broadcast without incorporation. U.S.
poultry production expanded over the 2011–20 period, as producers sought to meet increased
demand.25 The increased use of poultry manure (a solid form) with limited incorporation options
may explain some of the notable increase in unincorporated manure.
There was a significant change in the marketing and acceptance of manure as a nutrient source
between the CEAP survey periods, suggesting continuing opportunities for improving the use of
the resource. The most notable shift was the nearly threefold increase in acres applying
purchased manure. While manure applied on operations where it was produced still accounted
for most manured acres, that segment declined by 13 percent (2.5 million acres). Acres on which
users were compensated to receive and apply manure increased by nearly 900,000 acres (131
percent), indicating that livestock producers continue to seek ways to get manure on more acres
(table 17).
Table 17. Cultivated Cropland with Manure Applied, by Source, CEAP I and CEAP II
Source of Manure
On Operation
Off Operation
No Cost
Compensated
Purchased
Total

25

CEAP I

CEAP II

19,350
7,664
4,453
676
2,535
27,013

16,889
13,837
2,759
1,564
9,514
30,727

https://www.ers.usda.gov/topics/animal-products/poultry-eggs/sector-at-a-glance/

CEAP II CEAP I
Acres (1,000s)
-2,460
6,173
-1,694
888
6,979
3,713

Percent
Change
Relative to
CEAP I
-13
81
-38
131
275
14

46

Conservation Effects Assessment Project

HOW DID CONSERVATION ADOPTION AFFECT RESOURCE
CONCERNS?
Between the CEAP surveys, adoption of soil-conserving practices had a positive effect on
multiple cultivated cropland conditions—reducing erosion, increasing soil carbon, reducing
losses of sediment, and restricting some nutrient loss pathways. Loss thresholds were established
for each of these resource concerns to present an estimated conservation condition, assess
potential treatment needs, and provide context for potential future loss reductions.26 The
thresholds do not reflect or suggest conservation-related policy standards, and do not indicate
that any specific natural resource targets would be achieved if thresholds were met (e.g., water
quality standards). Meeting a threshold is not a static condition, as cultivated cropland may
experience periodic losses above or below a threshold under extreme conditions, such as
prolonged intense rainfall or drought.
Cultivated cropland meeting loss thresholds for erosion, sediment, surface nitrogen, and
sediment-transported phosphorus increased or remained stable, but declined for subsurface
nitrogen and soluble phosphorus between CEAP I and CEAP II. In both surveys, most of the
sediment, nitrogen, and phosphorus losses came from a small number of cultivated cropland
acres that exceeded specific loss thresholds. CEAP provides estimates of edge-of-field losses
through surface and subsurface pathways;27 however, the estimates do not suggest a particular
fate of transported materials (e.g., to water) or potential impact.

Erosion
Controlling soil erosion from water and wind is essential to maintaining soil health and
productivity and has been a longstanding conservation objective. Too much erosion on farm
fields creates challenges for sustaining soil productivity, while windborne soil or sediment
leaving a field can generate negative offsite impacts. Forms of water erosion on farm fields
include sheet and rill, ephemeral gully, and classic gully. Sheet and rill erosion is generally a
resource concern in higher rainfall areas and on steeper slopes. Wind erosion is primarily a
resource concern in arid and semiarid regions, although it can also be a problem in wetter regions
or on certain organic soils. Conservation practices such as conservation tillage, conservation crop
rotations, cover crops, and structural practices all help control erosion. In regions with low
rainfall, vegetative structural wind erosion control practices are constrained as they compete with
crops for limited water supplies.
The concept of soil loss tolerance is used to aid in understanding the potential effects of soil
erosion on soil productivity. The soil loss tolerance rate—“T”—reflects the estimate of annual
soil loss that can occur and still permit crop productivity to be sustained economically and
indefinitely on a given soil. The T value varies by soil, with deeper, uniform soils having higher
26

Threshold levels were derived through a series of forums with technical experts and refined by further
examination of model output to establish thresholds that were agronomically feasible and could be achieved with
existing production and conservation technology. Criteria used to establish these thresholds were refined for CEAP
II, so the CEAP I findings reported here will differ from those found in previous CEAP I reports.
27
Subsurface loss estimates include natural lateral drainage, deep drainage, and tile and ditch drains.

Conservation Practices on Cultivated Cropland

47

T values than shallow or previously eroded soils. Examining erosion levels relative to their T
value provides one way to assess whether fields are stable or declining.
Sheet and Rill Erosion
Between CEAP I and CEAP II, average annual sheet and rill erosion on cultivated cropland
dropped by over 76 million tons per year, a 13-percent reduction relative to CEAP I (table 18).
Rates declined from 1.9 tons per acre per year (t/a/y) to 1.7 tons t/a/y over the decade.
In CEAP I and CEAP II, most cultivated cropland acres met the threshold (soil T) at 89 percent
and 90 percent, respectively. As a result of the increase in conservation tillage and structural
practices, cultivated cropland meeting the threshold increased by over 6.5 million acres and
cultivated cropland exceeding the threshold dropped by 4.3 million acres, 12 percent from CEAP
I levels (table 18; appendix 2, table A-14).
Total sheet and rill erosion on cultivated cropland meeting the threshold dropped by 30.6 million
tons, an 11-percent reduction from CEAP I levels. Erosion on acres exceeding T dropped by 45.8
million tons, a 14-percent reduction from CEAP I levels. Most erosion continued to come from
the acres exceeding T; 55 percent of total sheet and rill erosion in both surveys came from
cultivated cropland eroding at rates above T although these acres accounted for only 11 and 10
percent of acres in CEAP I and CEAP II, respectively.
Table 18. Sheet and Rill Erosion by Threshold, CEAP I and CEAP II
CEAP I

Total
Meeting
Threshold
Exceeding
Threshold

Acres
(1,000s)

Percent

Tons
(1,000s)

313,065

100

277,546

89

35,519

11

CEAP II
Percent

Acres
(1,000s)

598,623

100

266,834

45

331,789

55

CEAP II minus CEAP I
Percent
Percent
Tons
Relative
Relative to
(1,000s)
to CEAP I
CEAP I
1
-76,360
-13

Percent

Tons
(1,000s)

Percent

Acres
(1,000s)

315,303

100

522,263

100

2,238

284,132

90

236,252

45

6,586

2

-30,583

-11

31,171

10

286,012

55

-4,348

-12

-45,777

-14

The North Central and Midwest region, with nearly 40 percent of all cultivated cropland,
accounted for over 50 percent of the total sheet and rill erosion in CEAP II. The East Central,
Lower Mississippi and Texas Gulf Coast, and Southern and Central Plains had the next highest
loads, and together accounted for 28 percent of total sheet and rill erosion (fig. 30).
Between the surveys, the national average sheet and rill erosion rate on all cultivated cropland
dropped by 0.2 t/a/y. The Northeast region experienced the largest reduction at 1 t/a/y, and rate
reductions in the North Central and Midwest and Southern and Central Plains regions were the
same as the national average. The East Central and South Central regions with their generally
sloping landscapes and humid, high rainfall climate had the highest average sheet and rill erosion
rates in CEAP II at 4.1 t/a/y.
Rainfall and inherent soil runoff vulnerability are the primary forces driving sheet and rill
erosion on cultivated cropland (box 6, page 50). Over 77 percent of the cultivated cropland with
sheet and rill erosion exceeding the threshold receives average annual rainfall of 35 inches or
more, and most of those acres have moderately high or high vulnerability to runoff (table 19).

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Conservation Effects Assessment Project

Figure 30. Sheet and Rill Erosion on Cultivated Cropland Relative to Threshold, CEAP I and CEAP II

Conservation Practices on Cultivated Cropland

49

Table 19. Cultivated Cropland with Sheet and Rill Erosion above T by Soil Vulnerability Runoff and
Rainfall, CEAP II
SVI Runoff
Rating
Low
Moderate
Moderately
High
High
National

< 15 inches
Acres
Percent
(1,000s)
of SVI
0
0
-

> 15 and < 25 inches
Acres
Percent
(1,000s)
of SVI
0
192
2

Average Annual Rainfall
> 25 and < 35 inches
> 35 and < 45 inches
Acres
Percent
Acres
Percent
(1,000s)
of SVI
(1,000s)
of SVI
465
1
474
1
328
5
1,011
9

> 45 inches
Acres
Percent
(1,000s)
of SVI
2,283
9
1,757
12

0

-

374

4

2,492

17

5,472

31

4,027

46

0
0

-

536
1,101

11
1

2,717
6,002

28
8

6,221
13,178

48
16

2,823
10,890

71
21

Between the CEAP surveys, cultivated cropland exceeding the sheet and rill threshold decreased
overall and in all vulnerability categories (fig. 31). However, most acres exceeding the threshold
remained in the high and moderately high vulnerability categories; 79 percent in CEAP II. While
most regions experienced a decline in high vulnerability acres exceeding the threshold, the South
Central and East Central regions experienced an increase. In three regions (East Central,
Northeast, and South Central), more than 20 percent of the regional cultivated cropland acres
exceed the sheet and rill threshold due to a mix of factors related to topography, annual rainfall,
and cropping systems.
Figure 31. Cultivated Cropland Exceeding Sheet and Rill Erosion Threshold by SVI-R and CEAP Survey

Wind Erosion
Between the two CEAP surveys, wind erosion dropped by nearly 94 million tons per year by
CEAP II, a 16-percent reduction relative to CEAP I. Rates dropped from an annual average of
1.9 t/a/y to 1.6 t/a/y.
Most cultivated cropland acres met the wind erosion threshold (soil T) at 88 percent in CEAP I
and 90 percent in CEAP II. Cultivated cropland meeting the wind erosion threshold increased by

50

Conservation Effects Assessment Project

Box 6. Controlling Erosion on Highly Erodible Land (HEL)
Between the CEAP surveys, major gains were made in controlling erosion on highly erodible land (HEL) cropland. Gains in
conservation tillage and structural practices on HEL helped to reduce losses, despite the overall increase in cultivation of HELdesignated cropland.
Sheet and rill erosion on HEL was reduced by over 39 million tons, 52 percent of the total sheet and rill erosion reduction
despite an increase in cultivation of 4.3 million acres. The average sheet and rill erosion rate on HEL dropped from 6.8 t/a/y to
5.1 t/a/y. Despite these gains, in CEAP II, HEL acres still accounted for 40 percent of total sheet and rill erosion while accounting
for only 13 percent of the acres.
Of the 41 million acres designated HEL for sheet and rill erosion in CEAP II, 40 percent were eroding above the tolerance rate
(T), down from 55 percent in CEAP I. The North Central and Midwest region alone accounted for 63 percent of HEL acres
eroding above T and 63 percent of the load from HEL. In CEAP II, four regions (Lower Mississippi and Texas Gulf, East Central,
Atlantic and Gulf Coastal Plains, and South Central regions) had over 50 percent of their respective regional HEL acres eroding
above T; these regions have high concentrations of low-residue crops (e.g., cotton and soybeans) and higher rainfall. Average
soil slopes on HEL cropland in the East Central region are among the highest of all regions.
Highly Erodible Cultivated Cropland Vulnerable to Sheet and Rill Erosion, CEAP I and CEAP II
CEAP I
CEAP II
HEL
NHEL
Total
HEL
NHEL
Total
Acres (1,000s)
37,017 276,048 313,065 41,392 273,911 315,303
Tons (1,000s)
250,734 347,889 598,623 211,319 310,944 522,263
Rate (t/a/y)
6.8
1.3
1.9
5.1
1.1
1.7
Percent Cultivated
12
88
13
87
Cropland Acres
Percent Tons Erosion
42
58
40
60

CEAP II minus CEAP I
HEL
NHEL
Total
4,375
-2,137
2,238
-39,415 -36,945 -76,360
-1.7
-0.1
-0.3
1.3

-1.3

-1.4

1.4

Losses on highly erodible land (HEL) cropland susceptible to wind erosion were reduced by nearly 22 million tons by CEAP II,
despite a 2.7-million-acre increase in cultivated acreage. The average wind erosion rate on HEL dropped from 5.3 t/a/y to 4.5
t/a/y. More remains to be done; although HEL cultivated cropland accounted for 14 percent of the acres, it generated 41
percent of wind erosion in CEAP II.
Of the 45.7 million acres designated HEL for wind erosion in CEAP II, 27 percent were eroding above the tolerance rate (T),
down from 37 percent in CEAP I. The Southern and Central Plains region alone accounted for 68 percent of HEL acres eroding
above T and 79 percent of the load from HEL. In CEAP II, two of the regions that are most susceptible to wind erosion (Southern
and Central Plains and Southwest regions) had over a third of their respective regional HEL acres eroding above T.
Highly Erodible Cultivated Cropland Vulnerable to Wind Erosion, CEAP I and CEAP II
CEAP I
CEAP II
HEL
NHEL
Total
HEL
NHEL
Total
Acres (1,000s)
42,908
270,156 313,065
45,665
269,638 315,303
Tons (1,000s)
228,677 374,928 603,605 206,914 302,826 509,740
Rate (t/a/y)
5.3
1.4
1.9
4.5
1.1
1.6
Percent Cultivated
14
86
14
86
Cropland Acres
Percent Tons Erosion
38
62
41
59

CEAP II minus CEAP I
HEL
NHEL
Total
2,757
-518
2,238
-21,763 -72,102 -93,865
-0.8
-0.3
-0.3
0.8

-0.8

2.7

-2.7

Conservation Practices on Cultivated Cropland

51

nearly 10 million acres between the surveys, while acres exceeding the threshold dropped by 7.6
million acres, 20 percent from CEAP I levels (table 20; appendix 2, table A-15).
Table 20. Wind Erosion by Threshold, CEAP I and CEAP II
CEAP I

Total
Meeting
Threshold
Exceeding
Threshold

Acres
(1,000s)

Percent

Tons
(1,000s)

313,065

100

274,431

88

38,634

12

CEAP II
Percent

Acres
(1,000s)

603,605

100

258,919

43

344,686

57

CEAP II minus CEAP I
Percent
Percent
Tons
Relative
Relative to
(1,000s)
to CEAP I
CEAP I
1
-93,865
-16

Percent

Tons
(1,000s)

Percent

Acres
(1,000s)

315,303

100

509,740

100

2,238

284,309

90

197,904

39

9,878

4

-61,015

-24

30,994

10

311,836

61

-7,640

-20

-32,850

-10

Most of the total reduction in tons of wind erosion on cultivated cropland came from acres
meeting the threshold, which dropped by 61 million tons, or 65 percent of the total. Wind erosion
from cultivated cropland exceeding the threshold dropped by 32.8 million tons (35 percent of the
total). By CEAP II, cultivated cropland with wind erosion exceeding the threshold accounted for
only 10 percent of acres in CEAP II, but generated 61 percent of the total wind erosion load (fig.
32).
The primary regions with wind erosion concerns are the Northern Plains, Northwest, Southern
and Central Plains, and Southwest. Of these, the Northern Plains and Southern and Central Plains
regions account for 36 percent of total cultivated cropland acres but 77 percent of total wind
erosion in CEAP II.
Between the surveys, the national average wind erosion rate on all cultivated cropland dropped
by 0.3 t/a/y. The Southwest region experienced the largest reduction at 2.4 t/a/y, and rate
reductions in the Northwest and Southern and Central Plains regions were greater than the
national average, at 0.8 and 0.7 t/a/y, respectively. Despite declines, the Northern Plains,
Northwest, Southern and Central Plains, and Southwest still had the highest average wind
erosion rates in CEAP II.
Inherent wind vulnerability and arid/semiarid conditions are the primary forces driving wind
erosion on cultivated cropland. Nearly 81 percent of the cultivated cropland with wind erosion
exceeding the threshold receives less than 25 inches of rainfall annually, and most of those acres
have moderately high or high wind vulnerability (table 21).
Between the CEAP surveys, cultivated cropland exceeding the wind threshold decreased overall
and in all vulnerability categories (fig. 33). However, most exceeding acres remained in the
moderately high and moderate vulnerability categories; 84 percent in CEAP II. While most
regions experienced a decline in moderately high vulnerability acres exceeding the threshold, the
Northern Plains and North Central and Midwest regions experienced an increase. In three regions
(Northern Plains, Southern and Central Plains, and Southwest), more than 20 percent of the
regional cultivated cropland acres exceeded the wind threshold due to a mix of factors related to
climate and cropping systems.

52

Conservation Effects Assessment Project

Figure 32. Wind Erosion on Cultivated Cropland Relative to Threshold, CEAP I and CEAP II

Conservation Practices on Cultivated Cropland

53

Table 21. Cultivated Cropland with Wind Erosion above T by Soil Vulnerability Wind and Rainfall, CEAP II
SVI Wind
Rating
Low
Moderate
Moderately
High
High
National

< 15 inches
Acres
Percent
(1,000s)
of SVI
0
0
24
7

> 15 and < 25 inches
Acres
Percent
(1,000s)
of SVI
0
0
8,915
17

Average Annual Rainfall
> 25 and < 35 inches > 35 and < 45 inches
Acres
Percent
Acres
Percent
(1,000s)
of SVI
(1,000s)
of SVI
1,721
3
632
1
1,303
11
0
-

> 45 inches
Acres
Percent
(1,000s)
of SVI
59
0
0
-

3,797

17

10,708

39

2,155

41

0

-

0

-

276
4,097

39
18

1,366
20,989

54
25

37
5,217

19
7

0
632

1

0
59

0

Figure 33. Cultivated Cropland Exceeding Wind Erosion Threshold by SVI-W and CEAP Survey

Sediment
Between CEAP I and CEAP II, total sediment losses dropped by 74 million tons (22 percent), as
farmers applied conservation measures on cultivated cropland and moved acres to higher
sediment management levels. Three regions (North Central and Midwest, Lower Mississippi and
Texas Gulf Coast, and Southern and Central Plains) accounted for 77 percent of the total
reduction. However, these three regions plus the East Central still accounted for 76 percent of the
total sediment load in CEAP II (fig. 34).
Average sediment loss on cultivated cropland dropped from 1.1 tons per acre per year to 0.9
t/a/y. The Northeast region experienced the largest reduction at 0.7 t/a/y, and rate reductions in
the Lower Mississippi and Texas Gulf Coast and North Central and Midwest regions also
exceeded the national average. The East Central and South Central regions—with their generally
sloping landscapes and humid, high rainfall climate—had the highest average sediment loss rates
in CEAP II at 2.4 and 2.6 t/a/y, respectively.
In both surveys, most cultivated cropland acres met the sediment threshold (2 t/a/y)—88 percent
in CEAP I and 91 percent in CEAP II (table 22). As cultivated cropland meeting the threshold
increased by 11 million acres over the decade, sediment loss on these acres declined by nearly
12.7 million tons.

54

Conservation Effects Assessment Project

Figure 34. Cultivated Cropland and Sediment Load Relative to Sediment Threshold (Acres and Tons), CEAP
I and CEAP II

Conservation Practices on Cultivated Cropland

55

Cultivated cropland exceeding the sediment threshold dropped by nearly 9 million acres, from 12
percent to 9 percent between CEAP I and CEAP II. The associated sediment load declined by
61.5 million tons, or 83 percent of the total reduction. However, cultivated cropland exceeding
the sediment threshold remains the largest source, with 9 percent of the acres delivering 68
percent of the total sediment load in CEAP II (table 22; appendix 2, table A-16).
Table 22. Sediment Loss by Threshold, CEAP I and CEAP II
CEAP I
Acres
(1,000s)

Percent

Tons
(1,000s)

Percent

Acres
(1,000s)

Percent

Tons
(1,000s)

Percent

100

337,635

100

315,303

100

263,455

100

CEAP II minus CEAP I
Percent
Percent
Relative
Relative
Acres
Tons
to
to
(1,000s)
(1,000s)
CEAP I
CEAP I
2,238
1
-74,181
-22

88

95,946

28

285,968

91

83,218

32

11,016

4

-12,728

-13

12

241,689

72

29,335

9

180,237

68

-8,778

-23

-61,452

-25

Total
313,065
Meeting
274,952
Threshold
Exceeding
38,113
Threshold

CEAP II

By CEAP II, three regions (North Central and Midwest, East Central, and Lower Mississippi and Texas
Gulf Coast) accounted for 74 percent of the total acres exceeding the sediment threshold and 73 percent
of the associated sediment losses.

Rainfall and inherent soil runoff vulnerability are the primary forces driving sediment loss from
cultivated cropland (see also box 3, page 18). Of the 29.3 million cultivated cropland acres
exceeding the sediment threshold in CEAP II, 22.2 million (76 percent) were in areas with more
than 35 inches of annual rainfall, and 15.2 million acres (69 percent) had moderately high and
high runoff vulnerability (table 23). Of all cultivated cropland acres with high runoff
vulnerability and more than 45 inches of rain annually (3.9 million acres), 65 percent (2.5 million
acres) exceeded the sediment loss threshold.
Table 23. Cultivated Cropland Exceeding the Sediment Threshold by Soil Vulnerability Index Runoff and
Rainfall, CEAP II
SVI Runoff
Rating
Low
Moderate
Moderately
High
High
National

< 15 inches

> 15 and < 25
inches
Acres
Percent
of SVI
(1,000s)
124
0
152
2

Average Annual Rainfall
> 25 and < 35
> 35 and < 45
inches
inches
Acres
Percent
Acres
Percent
of SVI
of SVI
(1,000s)
(1,000s)
344
1
407
1
296
4
913
8

Acres
(1,000s)
11
60

Percent
of SVI
0
2

36

0

201

2

2,498

17

3,749

21
128

1
1

785
1,262

16
2

2,595
5,733

27
8

5,507
10,576

> 45 inches
Acres
(1,000s)
3,181
2,487

Percent
of SVI
13
17

22

3,401

39

42
13

2,566
11,636

65
22

Between the CEAP surveys, cultivated cropland exceeding the sediment loss threshold decreased
overall and in all vulnerability categories (fig. 35). However, most acres exceeding the threshold
remained in the high and moderately high vulnerability categories; 73 percent in CEAP II. All
regions experienced a decline in moderately high vulnerability acres exceeding the threshold,
while only five regions experienced declines in all vulnerability categories (North Central and
Midwest, Northern Plains, Northeast, Northwest, and Southern and Central Plains). Four regions
(East Central, Lower Mississippi and Texas Gulf Coast, Northeast, and South Central) had more
than 20 percent of their regional cultivated cropland acres exceed the sediment threshold due to a
mix of factors related to climate and cropping systems.

56

Conservation Effects Assessment Project

Figure 35. Cultivated Cropland Exceeding the Sediment Threshold by Region and SVI-R, CEAP I and CEAP
II

Surface Nitrogen
Surface losses of nitrogen declined slightly between CEAP I and CEAP II, with only 11 percent
of cultivated cropland acres exceeding the threshold of 15 pounds per acre per year (lbs/a/y) in
both surveys (table 24; appendix 2, table A-17). In CEAP II, the 11 percent of acres exceeding
the threshold generated 48 percent of the total surface nitrogen loss. The majority (65 percent) of
the acres meeting the surface loss threshold were losing less than 5 lbs/a/y, helping to offset the
per-acre increase in losses on acres exceeding the threshold and resulting in the net reduction in
surface nitrogen loss.
Table 24. Surface Nitrogen Loss by Threshold, CEAP I and CEAP II
CEAP I

Total
Meeting
Threshold
Exceeding
Threshold

CEAP II

CEAP II minus CEAP I
Percent
Percent
Acres
Tons
Relative
Relative
(1,000s)
(1,000s)
to
to
CEAP I
CEAP I
2,238
1
-35
-3

Acres
(1,000s)

Percent

Tons
(1,000s)

Percent

Acres
(1,000s)

Percent

Tons
(1,000s)

Percent

313,065

100

1,073

100

315,303

100

1,038

100

277,981

89

621

58

281,357

89

541

52

3,376

1

-80

-13

35,084

11

452

42

33,946

11

497

48

-1,138

-3

45

10

While most regions experienced a decline in cultivated cropland exceeding the surface loss
threshold, the Northern Plains experienced an increase of more than 2.8 million such acres. Two
regions (North Central and Midwest and Southern and Central Plains) accounted for a 4-millionacre decline in cultivated cropland exceeding the surface nitrogen loss threshold (fig. 36).
Rainfall and inherent soil runoff vulnerability are the primary forces driving surface nitrogen loss
from cultivated cropland. Of the 33.9 million cultivated cropland acres exceeding the surface
nitrogen loss threshold in CEAP II, most were in areas receiving between 15 and 25 inches of
rainfall annually (table 25). Some 18.8 million (55 percent) were in areas receiving more than 25
inches of rainfall, down from 62 percent in CEAP I, while cultivated cropland receiving less than

Conservation Practices on Cultivated Cropland

57

Figure 36. Cultivated Cropland Relative to Surface Nitrogen Loss Threshold (Acres and Tons), CEAP I and
CEAP II

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Conservation Effects Assessment Project

Table 25. Cultivated Cropland Exceeding Surface Nitrogen Threshold by SVI Runoff and Rainfall, CEAP II
< 15 inches
SVI Runoff
Rating
Low
Moderate
Moderately
High
High
National

> 15 and < 25
inches
Acres
Percent
of SVI
(1,000s)
9,273
16
2,448
26

Average Annual Rainfall
> 25 and < 35
> 35 and < 45
inches
inches
Acres
Percent
Acres
Percent
of SVI
of SVI
(1,000s)
(1,000s)
2,561
6
380
1
667
9
674
6

Acres
(1,000s)
1,132
140

Percent
of SVI
11
6

294

4

855

9

1,998

14

2,165

8
1,574

0
7

1,025
13,601

21
16

1,883
7,108

20
10

3,161
6,380

> 45 inches
Acres
(1,000s)
521
930

Percent
of SVI
2
6

12

2,175

25

24
8

1,656
5,282

42
10

25 inches of rainfall and exceeding the surface nitrogen loss threshold increased by 15 percent.
Of all cultivated cropland acres with a high SVI-R and receiving more than 45 inches of rain
annually, 42 percent (1.7 million acres) exceeded the surface nitrogen threshold, reflecting the
difficulty in managing losses under these conditions.
Cultivated cropland exceeding the surface nitrogen threshold declined overall and in most
regions between CEAP I and CEAP II (fig. 37). Exceeding acres with high or moderately high
runoff vulnerability declined in all but the East Central, Northern Plains, Northeast, and South
Central. In the Northern Plains, the largest increase was in low vulnerability acres exceeding the
surface nitrogen loss threshold, reflecting the increase in nutrient application rates and decline in
nutrient incorporation in the region. In two regions (Northern Plains and South Central) more
than 20 percent of the regional cultivated cropland acres exceeded the surface nitrogen threshold
due to a mix of factors related to climate and cropping systems.
Figure 37. Cultivated Cropland Exceeding the Surface Nitrogen Threshold by SVI-R and CEAP Survey

Conservation Practices on Cultivated Cropland

59

Sediment-Transported Phosphorus
Sediment-transported phosphorus losses dropped by 14,000 tons between CEAP I and CEAP II,
as cultivated cropland acreage exceeding the loss threshold (greater than 3 lbs/a/y) decreased by
nearly 1.6 million acres (table 26; appendix 2, table A-18). The edge-of-field phosphorus losses
on acres exceeding the threshold, however, stayed relatively level, suggesting increases in peracre losses. By CEAP II, the 11 percent of acres exceeding the threshold accounted for 61
percent of the total sediment-transported loss. The 89 percent of acres meeting the threshold had
a 14-percent reduction in losses over the decade despite an increase of 3.8 million acres.
Table 26. Sediment-Transported Phosphorus Loss by Threshold, CEAP I and CEAP II
CEAP I
Acres
(1,000s)
Total
313,065
Meeting
277,854
Threshold
Exceeding
35,211
Threshold

CEAP II

CEAP II minus CEAP I
Percent
Percent
Relative
Relative
Acres
Tons
to
to
(1,000s)
(1,000s)
CEAP I
CEAP I
2,238
1
-14
-6

Percent

Tons
(1,000s)

Percent

Acres
(1,000s)

Percent

Tons
(1,000s)

Percent

100

227

100

315,303

100

213

100

89

97

43

281,673

89

83

39

3,819

1

-13

-14

11

130

57

33,630

11

129

61

-1,581

-4

-1

-1

Most regions experienced a decline in acres exceeding the sediment-transported phosphorus
threshold; the Northern Plains was a notable exception with an increase of 2 million acres. The
Southern and Central Plains region had the largest decline in cultivated cropland exceeding the
threshold, at 1.7 million acres. The region also experienced a net decline in cultivated cropland
over the decade. The North Central and Midwest region experienced the largest increase in
cultivated cropland meeting the threshold, gaining 4.2 million acres between the survey periods
(fig. 38).
Rainfall and inherent soil runoff vulnerability are the primary forces driving sedimenttransported phosphorus loss from cultivated cropland. Of the 33.6 million cultivated cropland
acres exceeding the loss threshold in CEAP II, most were in areas receiving more than 25 inches
of rainfall annually, nearly 26 million acres (77 percent) and of these most were in high and
moderately high vulnerability categories (65 percent) (table 27). Unexpected is the number of
low-runoff-vulnerability acres exceeding the threshold (33 percent of all cultivated cropland with
low runoff vulnerability), suggesting the effects of increased nutrient application rates and
reduction in nutrient incorporation. Of all cultivated cropland acres with a high SVI-R and
receiving more than 45 inches of rain annually, 55 percent (2.1 million acres) exceeded the
sediment-transported phosphorus threshold, reflecting the difficulty in managing losses under
these wet conditions.

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Conservation Effects Assessment Project

Figure 38. Cultivated Cropland Relative to Sediment-Transported Phosphorus Loss Threshold (Acres and
Tons), CEAP I and CEAP II

Conservation Practices on Cultivated Cropland

61

Table 27. Cultivated Cropland Exceeding Sediment-Transported Phosphorus Threshold by SVI Runoff and
Rainfall, CEAP II
SVI Runoff
Rating
Low
Moderate
Moderately
High
High
National

Average Annual Rainfall
> 15 and < 25
> 25 and < 35
> 35 and < 45
< 15 inches
> 45 inches
inches
inches
inches
Acres Percent of Acres Percent of Acres Percent of Acres Percent of Acres
Percent of
SVI
SVI
SVI
SVI
(1,000s)
(1,000s)
(1,000s)
(1,000s)
(1,000s)
SVI
833
8
4,227
7
2,160
5
2,152
5
1,929
8
25
1
734
8
449
6
791
7
1,559
11
399
38
1,295

5
2
6

635
775
6,372

6
16
8

2,572
2,158
7,339

18
23
10

2,946
4,104
9,992

17
31
12

2,949
2,195
8,633

Cultivated cropland exceeding the sediment-transported phosphorus threshold declined overall
and in most regions between CEAP I and CEAP II (fig. 39). Nationally, acres exceeding the
threshold with high runoff vulnerability remained relatively stable, acres with moderately high
and low vulnerability increased significantly, and acres with moderate vulnerability declined.
The Northern Plains and Southern Plains regions each had a significant increase in lowvulnerability acres exceeding the sediment-transported phosphorus loss threshold, reflecting the
increase in nutrient application rates and decline in nutrient incorporation in those regions. In
three regions (East Central, Northeast, and South Central) more than 20 percent of the regional
cultivated cropland acres exceeded the sediment-transported phosphorus threshold due to a mix
of factors related to climate and cropping systems. While most regions followed the national
pattern, there were exceptions, notably the North Central and Midwest region, which had an
increase in high vulnerability acres (over 1 million acres) and a decrease in low vulnerability
acres (2.4 million acres) exceeding the threshold.
Figure 39. Cultivated Cropland Exceeding Sediment-Transported Phosphorus Threshold by Region and SVIR, CEAP I and CEAP II

33
55
16

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Conservation Effects Assessment Project

Subsurface Nitrogen
Although most acres met the subsurface nitrogen threshold in both survey periods, subsurface
nitrogen losses increased by 420,000 tons between CEAP I and CEAP II (table 28; appendix 2,
table A-19). Conservation tillage systems reduced the risk of nitrogen loss through surface
pathways and increased infiltration for subsurface flow, while the increase in surface application
of fertilizer promoted surface conversion to soluble nitrogen and movement through the soil
profile. Cultivated cropland exceeding the subsurface loss threshold (greater than 25 lbs/a/y)
increased by over 14 million acres (19 percent), while acres meeting the threshold declined by
almost 12 million acres (5 percent). Losses from acres exceeding the threshold increased by
442,000 tons, resulting in losses 20 percent higher than the CEAP I level and only slightly offset
by the decline in losses from acres meeting the threshold.
Table 28. Subsurface Nitrogen Loss by Threshold, CEAP I and CEAP II
CEAP I

Total
Meeting
Threshold
Exceeding
Threshold

CEAP II

Acres
(1,000s)

Percent

Tons
(1,000s)

Percent

Acres
(1,000s)

Percent

Tons
(1,000s)

Percent

313,065

100

3,130

100

315,303

100

3,550

100

CEAP II minus CEAP I
Percent
Percent
Relative
Relative
Acres
Tons
to
to
(1,000s)
(1,000s)
CEAP I
CEAP I
2,238
1
420
13

238,286

76

971

31

226,389

72

949

27

-11,897

-5

-22

-2

74,779

24

2,159

69

88,914

28

2,601

73

14,135

19

442

20

By CEAP II, 28 percent of cultivated cropland acres exceeded the subsurface nitrogen loss
threshold and accounted for 73 percent of the total subsurface nitrogen losses (fig. 40). About
half of the acres that met the subsurface threshold were losing less than 13 lbs/a/y. Timing
nutrient applications with crop demand and incorporating applications are particularly critical
practices as there are few edge-of-field options for trapping subsurface flow. In addition, without
attention to timing and incorporation, increased rates may even lead to reduced yields as
increased losses reduce nutrient-use efficiencies.
The North Central and Midwest and the Northern Plains regions accounted for 76 percent of the
total increase in acres exceeding the subsurface loss threshold, each having individual increases
of over 5 million acres. In the Northern Plains region, that increase more than doubled the acres
exceeding the threshold. In the larger North Central and Midwest region, 31 percent of cultivated
cropland exceeded the subsurface nitrogen loss threshold in CEAP II, an increase of 17 percent
from CEAP I levels (fig. 40).
Rainfall and inherent soil leaching vulnerability are the primary forces driving subsurface
nitrogen loss from cultivated cropland. Of the 88.9 million cultivated cropland acres exceeding
the loss threshold in CEAP II, nearly 55 million acres (62 percent) were in areas receiving more
than 35 inches of rainfall annually. Of these acres, 60 percent were in high and moderately high
leaching vulnerability categories (table 29). Across all rainfall categories, most of the acres
exceeding the threshold were in the high (39 percent) or moderate (35 percent) leaching
vulnerability categories. Of all cultivated cropland acres with a high SVI-L and receiving more
than 45 inches of rain annually, 57 percent (7.3 million acres) exceeded the subsurface nitrogen
threshold, reflecting the difficulty in managing subsurface losses under high rainfall conditions.

Conservation Practices on Cultivated Cropland

63

Figure 40. Cultivated Cropland Relative to Subsurface Nitrogen Loss Threshold (Acres and Tons), CEAP II

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Conservation Effects Assessment Project

Table 29. Cultivated Cropland Exceeding Subsurface Nitrogen Threshold by SVI Leaching (SVI-L) and
Rainfall, CEAP II
SVI
Leaching
Rating
Low
Moderate
Moderately
High
High
National

Average Annual Rainfall
> 15 and < 25
> 25 and < 35
> 35 and < 45
< 15 inches
> 45 inches
inches
inches
inches
Acres
Percent
Acres Percent of Acres Percent of Acres Percent of Acres
Percent
SVI
SVI
SVI
(1,000s)
of SVI (1,000s)
(1,000s)
(1,000s)
(1,000s)
of SVI
186
9
463
12
1,469
20
2,321
22
2,303
39
2,551
15
6,289
12
5,264
14
9,290
30
8,082
47
110

21

1,229

23

1,367

30

4,701

41

8,412

51

826
3,673

30
16

5,687
13,669

29
17

8,574
16,675

34
23

12,462
28,775

41
35

7,326
26,123

57
50

Cultivated cropland exceeding the subsurface nitrogen threshold increased overall and in most
regions between CEAP I and CEAP II (fig. 41). Acres exceeding the threshold with high,
moderate, and low leaching vulnerability increased, while there was a slight decline in
moderately high acres. The North Central and Midwest and Northern Plains regions each had a
significant increase in high vulnerability acres exceeding the surface nitrogen loss threshold. The
Southwest was the only region with a decline in acres exceeding the threshold in all vulnerability
categories. In nine regions more than 20 percent of the regional cultivated cropland acres
exceeded the subsurface nitrogen threshold reflecting the decline in nutrient management that
occurred between the surveys and the difficulties in controlling subsurface flow.
Figure 41. Cultivated Cropland Exceeding Subsurface Nitrogen Threshold by SVI-L and CEAP Survey

Soluble Phosphorus
Soluble phosphorus losses increased by 7,200 tons (11 percent) between the survey periods
(table 30; appendix 2, table A-20). Cultivated cropland exceeding the soluble phosphorus loss
threshold (greater than 0.5 lbs/a/y) increased by 11.4 million acres (16 percent) while acres
meeting the threshold declined by 9.2 million acres (4 percent). Phosphorus losses from acres
exceeding the threshold increased by 6,600 tons, or 15 percent from CEAP I levels, and

Conservation Practices on Cultivated Cropland

65

increased slightly on acres meeting the threshold. By CEAP II, 27 percent of cultivated cropland
acres exceeded the threshold and accounted for 73 percent of the total soluble phosphorus losses.
The probability of meeting the soluble loss threshold is increased with incorporation of applied
nutrients, which becomes more important as rates increase.
Table 30. Soluble Phosphorus Loss by Threshold, CEAP I and CEAP II
CEAP I

Total
Meeting
Threshold
Exceeding
Threshold

CEAP II
Acres
(1,000s)

CEAP II minus CEAP I
Percent
Percent
Tons
Relative to
Relative to
(1,000s)
CEAP I
CEAP I
1
7.2
11

Acres
(1,000s)

Percent

Tons
(1,000s)

Percent

Acres
(1,000s)

Percent

Tons
(1,000s)

Percent

313,065

100

63

100

315,303

100

70

100

2,238

240,156

77

18

29

230,942

73

19

27

-9,214

-4

0.6

3

72,909

23

45

71

84,361

27

51

73

11,452

16

6.6

15

Most regions experienced an increase in acres exceeding the soluble phosphorus loss threshold.
The North Central and Midwest region had an increase of nearly 9 million acres exceeding the
threshold by CEAP II, more than twice that of the other gaining regions. The Northern Plains
gained nearly 2.5 million acres meeting the threshold, while most regions lost acres in that
category (fig. 42).
Rainfall and inherent soil runoff vulnerability are the primary forces driving soluble phosphorus
loss from cultivated cropland. Of the 84.4 million cultivated cropland acres exceeding the loss
threshold in CEAP II, most were in areas receiving 35 inches or more of rainfall annually—
nearly 74 million acres (88 percent)—and of these nearly 50 percent had low runoff vulnerability
(table 31). Across all rainfall categories, about half of the acres exceeding the threshold (41.7
million acres) had low runoff vulnerability. Of all cultivated cropland acres with a high SVI-R
and receiving more than 45 inches of rain annually, 79 percent (3.1 million acres) exceeded the
soluble phosphorus threshold, reflecting the difficulty in managing soluble losses under high
rainfall conditions.
Cultivated cropland exceeding the soluble phosphorus threshold increased overall and in most
regions between CEAP I and CEAP II (fig. 43). Acres exceeding the threshold with high,
moderately high, and low runoff vulnerability increased, while there was a slight decline in
moderate vulnerability acres. The North Central and Midwest had a significant increase in high
vulnerability acres exceeding the threshold and was joined by the Lower Mississippi and Texas
Gulf Coast in a substantial increase in low vulnerability acres exceeding the threshold. In six
regions more than 20 percent of the regional cultivated cropland acres exceeded the soluble
phosphorus threshold reflecting the decline in nutrient management that occurred between the
surveys and the challenges in controlling soluble flow.

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Conservation Effects Assessment Project

Figure 42. Cultivated Cropland Relative to Soluble Phosphorus Loss Threshold (Acres and Tons), CEAP I
and CEAP II

Conservation Practices on Cultivated Cropland

67

Table 31. Cultivated Cropland Exceeding Soluble Phosphorus Threshold by SVI Runoff and Rainfall, CEAP
II
SVI Runoff
Rating
Low
Moderate
Moderately
High
High
National

Average Annual Rainfall
> 15 and < 25
> 25 and < 35
> 35 and < 45
< 15 inches
> 45 inches
inches
inches
inches
Acres Percent of Acres Percent of Acres Percent of Acres Percent of Acres
Percent
SVI
SVI
SVI
SVI
(1,000s)
(1,000s)
(1,000s)
(1,000s)
(1,000s)
of SVI
345
3
1,022
2
4,664
11
17,768
43
17,953
71
85
4
38
0
870
12
4,834
42
11,335
78
92

1

120

1

1,863

13

6,505

37

6,838

77

38
560

2
2

198
1,377

4
2

1,034
8,431

11
11

5,619
34,725

43
42

3,141
39,267

79
75

Figure 43. Cultivated Cropland Exceeding Soluble Phosphorus Threshold by Region and SVI-R, CEAP I and
CEAP II

Soil Carbon
Between the CEAP surveys, soil carbon gains on all cultivated cropland increased by over 8.8
million tons per year because of soil-conserving measures applied by farmers. By CEAP II,
cultivated cropland meeting the soil carbon threshold (gaining or maintaining soil carbon)
increased by 3.4 million acres; cultivated cropland gaining carbon increased by 25.7 million
acres and cultivated cropland maintaining soil carbon declined by 22.3 million acres. Cultivated
cropland exceeding the threshold (losing carbon) declined slightly (1.2 million acres) (fig. 44).
Average soil carbon change on all cultivated cropland increased from 144 to 192 lbs/a/y (33
percent). On the nearly 19 million acres where cover crops were part of the rotation in CEAP II,
rates of carbon gain were nearly 30 percent above the average gain on cultivated cropland where
cover crops were not in use (box 7, page 69).
Most regions had soil carbon gains between the two survey periods (fig. 45). Three regions, led
by the Southern and Central Plains, accounted for 75 percent of the total increase. These regions
also experienced significant increases in conservation tillage between the two CEAP surveys.

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Conservation Effects Assessment Project

Figure 44. Cultivated Cropland by Carbon Trend, CEAP I and CEAP II

Figure 45. Carbon Change by Region, CEAP I and CEAP II

As expected, most soils gaining carbon are under continuous no-till or reduced tillage, 41 and 37
percent respectively. However, more than 22 percent of acres under conventional tillage also
gained carbon, demonstrating that there are strategies that work for all tillage classes (fig. 46).
Nevertheless, nearly 60 percent of all acres losing carbon are conventionally tilled and could
benefit from additional conservation.
Multiple management and natural resource factors affect soil carbon storage. Inherent soil
vulnerability to erosion and runoff losses, low-residue cropping systems, and nutrient
management strategies that limit plant growth all can contribute to soils not maintaining or
gaining soil carbon. Of the 48.5 million cultivated cropland acres exceeding the carbon threshold
in CEAP II, over one-third were receiving between 15 and 25 inches of rainfall annually, and of
these most had low runoff vulnerability (table 32). Across all rainfall categories, about 60
percent of the exceeding acres (28.9 million acres) had low runoff vulnerability, up from 57

Conservation Practices on Cultivated Cropland

69

percent in CEAP I. Of all cultivated cropland acres with a high SVI-R and receiving more than
45 inches of rain annually, only 15 percent exceeded the carbon threshold, suggesting that while
rainfall and inherent vulnerability may affect soil carbon, other factors could have more
influence.
Three regions—North Central and Midwest, Northern Plains, and Lower Mississippi and Texas
Gulf Coast—drove the increase in cultivated cropland with low runoff vulnerability and
exceeding the carbon threshold between the survey periods (fig. 47; appendix 2, table A-21).
Box 7. Cover Crop Benefits
The estimated benefits on cultivated cropland with cover crops in CEAP II was compared to simulated losses with the cover
crops removed from the rotation. With cover crops, the losses of sediment were reduced by 17 percent, total nitrogen by 17
percent, and total phosphorus by 9 percent. Annual change in soil carbon increased by 30 percent.
Effects of Cover Crops on Selected Benefits
Benefit Summary

With Cover
Crop

Sediment Loss
Total Nitrogen Loss
Surface Nitrogen Loss
Subsurface Nitrogen Loss
Total Phosphorus Loss
Soluble Phosphorus Loss
Soil Carbon Gain

13,244,520
316,390
42,720
273,570
16,582
4,519
2,808,210

Without Cover
Crop
Tons/Year
15,987,435
379,708
46,535
333,173
18,284
4,758
2,164,961

Cover Crop Benefit
-2,742,915
-63,318
-3,815
-59,503
-1,702
-239
645,248

Percent
-17
-17
-8
-17
-9
-5
30

Farmers weigh the trade-offs in cover crop management decisions to achieve their objectives. For example, terminating a cover
crop with intense tillage may diminish its benefits for erosion reduction or soil condition. Conversely, cover crop residues left to
degrade naturally on the soil surface may contribute to an increase in soluble nitrogen or phosphorus losses. In arid and
semiarid regions, competition for water between cover and cash crops may affect adoption. Cover crop adoption over the
decade between the two surveys was highly concentrated in three regions—Atlantic and Gulf Coastal Plains, North Central and
Midwest, and Northern Plains—where 70 percent of the increase occurred.

Figure 46. Carbon Trends by Tillage Class, CEAP II

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Conservation Effects Assessment Project

Table 32. Cultivated Cropland Exceeding the Soil Carbon Threshold by SVI Runoff and Rainfall, CEAP II

SVI Runoff
Rating
Low
Moderate
Moderately
High
High
National

Average Annual Rainfall
> 15 and < 25
> 25 and < 35
> 35 and < 45
< 15 inches
> 45 inches
inches
inches
inches
Acres Percent of Acres Percent of Acres Percent of Acres Percent of Acres
Percent
SVI
SVI
SVI
SVI
(1,000s)
(1,000s)
(1,000s)
(1,000s)
(1,000s)
of SVI
2,042
19
12,301
21
6,140
14
5,189
13
3,219
13
373
15
2,008
22
1,310
18
1,738
15
1,888
13
767

10

1,445

15

2,026

14

1,710

10

1,564

18

406
3,588

19
16

932
16,686

19
20

823
10,299

9
14

2,046
10,683

16
13

584
7,255

15
14

Figure 47. Cultivated Cropland Exceeding the Carbon Threshold by Region and SVI-R, CEAP I and CEAP
II

Managing cultivated cropland for soil carbon is a complex process and requires a systems
approach to avoid negatively affecting other natural resources. For example, while soils gaining
carbon have lower nitrogen losses than those maintaining or losing carbon, there can still be
significant nitrogen loss. Soils gaining carbon with a low level of nitrogen management lose
more nitrogen than soils losing carbon but with a high level of management (table 33).
Improving soil health and increasing carbon storage in balance with sound nutrient management
can help to prevent unintended consequences.
Table 33. Nitrogen and Phosphorus Loss by Carbon Trend and Nutrient Management Level
Carbon Trend
Gaining
Maintaining
(>100 lbs/a/y)
Nutrient Management Level
Nitrogen Phosphorus Nitrogen Phosphorus
lbs/a/y
Low
47
4.8
76
5.8
Moderate
23
1.7
38
2.9
Moderately High
21
1.1
33
1.5
High
15
1
19
1.3

Losing
(<-100 lbs/a/y)
Nitrogen Phosphorus
105
61
59
36

7.6
6
3.7
3.2

Conservation Practices on Cultivated Cropland

71

Resource Concerns Summary
Conservation measures adopted by farmers between CEAP I and CEAP II helped to reduce field
losses of erosion, sediment, surface nitrogen, sediment-transported phosphorus, and soil carbon.
Correspondingly, the acres exceeding thresholds for those resource concerns declined as well
(table 34). However, for subsurface nitrogen and soluble phosphorus losses, acres exceeding loss
thresholds increased between the survey periods. These losses were driven by changes in nutrient
management practices and related to changes in cropping patterns. Over one-fourth of the
Nation’s cultivated cropland exceeded thresholds for subsurface nitrogen and soluble phosphorus
losses.
Table 34. Cultivated Cropland Exceeding Resource Concern Thresholds by Survey
CEAP I
Resource Concern (Loss
Threshold)
Sheet & Rill Erosion (>T)
Wind Erosion (>T)
Sediment (>2 t/a/y)
Surface Nitrogen (>15 lbs/a/y)
Sediment-Transported
Phosphorus (>3lbs/a/y)
Subsurface Nitrogen (>25 lbs/a/y)
Soluble Phosphorus (>0.5 lbs/a/y)
Soil Carbon (Maintaining/Losing)

CEAP II

CEAP II minus CEAP I
Percent of
Acres
Acres
(1,000s)
Relative to
CEAP I
-4,348
-12
-7,640
-20
-8,778
-23
-1,138
-3

Acres
(1,000s)

Percent of
Acres

Acres
(1,000s)

Percent of
Acres

35,519
38,634
38,113
35,084

11
12
12
11

31,171
30,994
29,335
33,946

10
10
9
11

35,211

11

33,630

11

-1,581

-4

74,779
72,909
49,703

24
23
16

88,914
84,361
48,511

28
27
15

14,135
11,452
-1,192

19
16
-2

The acres exceeding thresholds are not additive, and a single field or a single acre may exceed
more than one threshold. For example, an acre exceeding the sheet and rill erosion threshold may
also exceed the sediment loss threshold. Similarly, opportunities remain where conservation
measures are in place but the pressures on the land require more comprehensive treatment. For
example, regions with intense rainfall, steeper slopes, or prevalence of low residue, intensive
cropping systems often require additional conservation practices to meet loss thresholds.
Acres exceeding the thresholds were not evenly distributed, reflecting regional differences in
climate, soils, production practices, and crops, among others. Cultivated cropland exceeding the
wind threshold, for example, was concentrated in several western regions with arid and semiarid
conditions. Water-driven resource concerns such as subsurface nitrogen losses were concentrated
in regions with high rainfall and flatter terrain. Regional treatment priorities can be informed by
the percentage of regional acres exceeding resource concern thresholds (table 35). For example,
in the Northeast region, where nearly 50 percent of cultivated cropland exceeded the subsurface
nitrogen threshold and nearly 60 percent of the acres exceeded the soluble phosphorus threshold,
nutrient management would be a priority.
In most cases, cultivated cropland acres needing treatment to meet a resource concern threshold
are not contiguous but exist as isolated areas within larger fields—for example, soils vulnerable
to leaching within a field (box 8). Making progress begins with a field-scale resource assessment
and conservation planning to design workable solutions in balance with an operator’s economic
and environmental objectives. Solutions may include targeted conservation practices within a
systems approach, higher end technology, or some combination of these and other tools.

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Conservation Effects Assessment Project

Table 35. Percent Regional Acres Exceeding by Threshold, CEAP II *
Region

Wind
Erosion

Sheet &
Rill
Erosion

Sediment

Surface
Nitrogen

Sediment
Transported
Phosphorus

Atlantic and Gulf
0.0
14.5
12.0
3.5
11.6
Coastal Plains
California
0.0
1.0
5.1
1.3
1.6
Coastal
East Central
0.0
32.0
28.2
17.4
27.0
Lower Mississippi
2.6
16.3
24.4
10.9
13.6
and Texas Gulf
North Central and
1.5
13.2
11.0
7.3
11.1
Midwest
Northeast
0.0
31.5
23.2
13.8
30.7
Northern Plains
24.0
1.5
1.5
22.4
9.3
Northwest
13.9
0.6
3.5
4.5
6.2
South Central
2.1
28.5
32.6
26.0
23.9
Southern and
21.6
2.2
1.8
9.2
5.5
Central Plains
Southwest
25.2
2.8
3.8
4.5
4.3
National
9.8
9.9
9.3
10.8
10.7
* The highlighted cells indicate a regional percentage above the national average

Subsurface
Nitrogen

Soluble
Phosphorus

Carbon

59.7

68.9

15.1

33.5

17.0

38.7

49.7

73.6

13.6

47.3

77.6

14.2

31.1

32.5

12.8

49.6
19.5
20.0
40.0

58.9
1.5
6.5
50.6

20.3
19.8
13.9
29.6

10.8

2.2

14.1

24.0
28.2

9.2
26.8

25.2
15.4

Box 8. Treatment Needs at the Field Level
Within a given farm field, measures needed to meet resource concern thresholds vary, reflecting the diversity of soils and
vulnerabilities and highlighting the need for comprehensive conservation planning and integration of modern technologies such
as precision agriculture to address needs more efficiently. The acres exceeding surface or subsurface loss thresholds are
generally scattered, manifested as small, vulnerable inclusions in a larger field. The figure below shows a typical Midwestern
field with a combination of soils with low, moderate, and high vulnerability to runoff. In most cases, eliminating cultivation on
high and moderately high-risk soils embedded in a field is unrealistic, operationally and economically. Variable rate technology
(VRT) allows precision application of nitrogen or other inputs based on variations in the soil or the crop offering one method for
treating fields with multiple vulnerability zones. Where high risk acres are contiguous, at field edges or corners, conversion to
less intensive uses may prove economically effective. Irrespective of approach, addressing vulnerable soils and their needs
depends on conservation planning and targeting within the field to develop workable subfield treatments that minimize
potential losses.

Conservation Practices on Cultivated Cropland

73

HOW DID SEDIMENT AND NUTRIENT MANAGEMENT CHANGE?
Cultivated cropland acres were categorized by the level of sediment, nitrogen, and phosphorus
management being applied to allow comparison of conservation treatment between the two
CEAP survey periods. Combinations of soils, climate, and crop rotations are a few factors that
may affect the management level needed to maintain the resource. In general, higher levels of
management are needed as annual rainfall and soil vulnerability increase.
Cultivated cropland acres were placed into one of four management levels—high, moderately
high, moderate, and low—that consider the agricultural system in its entirety and the interactions
and potential effects of operational and conservation activities on the land. The criteria are based
on an Avoid, Control, and Trap approach to reducing sediment losses, and a Rate, Method, and
Timing approach to reducing nutrient losses from cultivated cropland (appendix 3). This systems
approach uses a mix of conservation practices tailored to the resource concern to minimize loss
potential and optimize agricultural inputs for productivity. As management levels increase, more
supporting practices are included.
The level of sediment, nitrogen, and phosphorus management on cultivated cropland changed
over the decade between the CEAP surveys, reflecting the shifts in conservation treatment. The
increase in conservation tillage and structural practices had a positive effect, most notably in
sediment management, but also in nitrogen and phosphorus management where some gains were
made in moderately high management levels. In contrast, the decline in nutrient management
practices, particularly increased application rates and incorporation declines, drove large drops in
high levels of management for nitrogen and phosphorus and corresponding increases in low
levels of management of both.

Sediment
Cultivated cropland with moderately high and high sediment management increased by 45
million acres, from 25 percent of acres in CEAP I to 40 percent of acres in CEAP II, reflecting
farmers’ increased adoption of conservation tillage and structural practices (table 36; appendix 2,
table A-22). By CEAP II, acres with high sediment management had increased by 150 percent
and acres with moderately high sediment management increased by 42 percent, while those in
moderate and low levels declined by 43 million acres (18 percent) as more cultivated cropland
moved to higher sediment management levels (fig. 48). Despite a 9-percent decline in acres with
moderate management levels and a 37-percent decline in acres with low management levels,
some 60 percent of cultivated cropland remained under moderate or low management for
sediment control.

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Conservation Effects Assessment Project

Table 36. Sediment Management Levels on Cultivated Cropland, CEAP I and CEAP II
CEAP I
Management
Level
National
High
Moderately
High
Moderate
Low

313,065
10,332

3

315,303
25,816

8

2,238
15,484

5

Percent
Change in
Acres from
CEAP I
1
150

69,900

22

99,490

32

29,590

10

42

155,923
76,910

50
25

141,210
48,787

45
15

-14,713
-28,123

-5
-10

-9
-37

Acres
(1000)

CEAP II

Percent

Acres
(1000)

CEAP II minus CEAP I

Percent

Acres
(1000)

Percent

Figure 48. Cultivated Cropland by Sediment Management Level, CEAP I and CEAP II

Production regions generally followed the national trend, with most showing increases in
moderately high and high sediment management and declines in moderate and low management
levels. Gains were concentrated in two regions—North Central and Midwest and Southern and
Central Plains (fig. 49). Together these regions accounted for three-fourths of the total increase
in cultivated cropland with moderately high and high levels of sediment management (33.7
million acres).
Sediment Management by Tillage System
The increase in conservation tillage and particularly in continuous no-till drove the increases in
sediment management levels experienced between CEAP I and CEAP II. Cultivated cropland
under reduced tillage and continuous no-till increased by 53 million acres; 83 percent of this
increased acreage was in high and moderately high levels of sediment management. Continuous
no-till with high sediment management increased by over 9 million acres (239 percent) (table
37). Conventional tillage experienced declines in all but the moderately high management
category, aligning with the general loss of acres under that form of tillage (fig. 50).

Conservation Practices on Cultivated Cropland
Figure 49. Sediment Management Levels on Cultivated Cropland by Region, CEAP I and CEAP II

75

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Conservation Effects Assessment Project

Table 37. Sediment Management on Cultivated Cropland by Tillage System and CEAP Survey
CEAP I

Tillage System /
Sediment
Management Level

Acres
(1,000s)

Conventional Tillage
High
Moderately High
Moderate
Low
Reduced Tillage
High
Moderately High
Moderate
Low
Continuous No-Till
High
Moderately High
Moderate
Low
National
High
Moderately High
Moderate
Low

155,941
0
3,005
76,026
76,910
95,572
6,515
39,240
49,817
0
61,553
3,817
27,655
30,081
0
313,065
10,332
69,900
155,924
76,910

CEAP II

Percent
50
0
2
49
49
31
7
41
52
0
20
6
45
49
0
3
22
50
25

Acres
(1,000s)
104,771
0
3,902
52,082
48,787
107,423
12,868
48,013
46,543
0
103,108
12,948
47,575
42,585
0
315,303
25,816
99,490
141,210
48,787

CEAP II minus CEAP I

Percent
33
0
4
50
47
34
12
45
43
0
33
13
46
41
0
8
32
45
15

Acres
(1,000s)
-51,170
0
897
-23,943
-28,123
11,851
6,353
8,772
-3,274
0
41,555
9,131
19,920
12,505
0
2,238
15,484
29,589
-14,712
-28,123

Percent
-17
0
2
1
-3
4
5
4
-9
0
13
6
1
-8
0
5
9
-5
-9

Percent
Change in
Acres from
CEAP I
-33
0
30
-31
-37
12
98
22
-7
0
68
239
72
42
0
1
150
42
-9
-37

Figure 50. Cultivated Cropland by Sediment Management Level and Tillage System, CEAP II minus CEAP I

Conservation Practices on Cultivated Cropland

77

Sediment Management on Vulnerable Acres
Between CEAP I and CEAP II, sediment management on cultivated cropland with high and
moderately high vulnerability to runoff (soil vulnerability index runoff [SVI-R]) increased,
reflecting the consistent movement into higher management levels (table 38; appendix 2, table
A-25). High and moderately high sediment management on high vulnerability acres increased by
9.5 million acres and by 11.8 million acres on cultivated cropland with moderately high runoff
vulnerability.
Table 38. Sediment Management Levels by Soil Vulnerability Index Runoff (SVI-R), CEAP I and CEAP II
Sediment
Management Level

High
Acres
(1,000s)

Percent
SVI
Acres

SVI R Rating
Moderately High
Moderate
Percent
Acres
Percent
Acres
SVI
(1,000s) SVI Acres (1,000s)
Acres

Low

National

Acres
Percent
Acres
(1,000s) SVI Acres (1,000s)

CEAP I
High
2,516
Moderately High
10,674
Moderate
11,368
Low
2,587
National
27,145
CEAP II
High
6,884
Moderately High
15,793
Moderate
9,363
Low
1,492
National
33,532
CEAP II minus CEAP I
High
4,367
Moderately High
5,119
Moderate
-2,005
Low
-1,094
National
6,387
Change Relative to CEAP I
High
4,367
Moderately High
5,119
Moderate
-2,005
Low
-1,094
National
6,387

9
39
42
10
9

2,169
16,714
25,638
9,200
53,721

4
31
48
17
17

1,401
9,815
26,419
16,899
54,534

3
18
48
31
17

4,245
32,697
92,498
48,225
177,665

2
18
52
27
57

10,332
69,900
155,923
76,910
313,065

21
47
28
4
11

6,438
24,266
23,277
4,184
58,165

11
42
40
7
18

2,477
11,003
23,269
8,033
44,781

6
25
52
18
14

10,018
48,429
85,300
35,079
178,825

6
27
48
20
57

25,816
99,490
141,210
48,787
315,303

11
8
-14
-5
2

4,269
7,552
-2,361
-5,016
4,444

7
11
-8
-10
1

1,076
1,187
-3,149
-8,866
-9,753

3
7
4
-13
-3

5,773
15,732
-7,198
-13,147
1,161

3
9
-4
-8
0

15,484
29,590
-14,713
-28,123
2,238

174
48
-18
-42
24

4,269
7,552
-2,361
-5,016
4,444

197
45
-9
-55
8

1,076
1,187
-3,149
-8,866
-9,753

77
12
-12
-52
-18

5,773
15,732
-7,198
-13,147
1,161

136
48
-8
-27
1

15,484
29,590
-14,713
-28,123
2,238

While high and moderately high sediment management levels increased in all vulnerability
ratings, the largest percentage increases were in the higher runoff vulnerability classes (high and
moderately high SVI-R) (fig. 51). Low sediment management was the reverse, declining in all
runoff vulnerability classes and reflecting the adoption of conservation tillage and structural
practices designed to control erosion and runoff.

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Conservation Effects Assessment Project

Figure 51. Change in Sediment Management on Cultivated Cropland by SVI-R, CEAP II minus CEAP I

Nitrogen
Between CEAP I and CEAP II, cultivated cropland with high nitrogen management declined by
over 36 million acres (27 percent), while acres with moderately high nitrogen management
increased by nearly 17 million acres (16 percent) (table 39; appendix 2, table A-23). By CEAP
II, cultivated cropland with moderately high nitrogen management had become the dominant
management class on cultivated cropland.
In contrast, cultivated cropland with moderate and low nitrogen management increased by nearly
21.7 million acres, reflecting the decline in nutrient management practices between the surveys
(fig. 52). In CEAP II, over 70 percent of cultivated cropland was under high or moderately high
nitrogen management, down from 77 percent in CEAP I.
Table 39. Nitrogen Management Levels on Cultivated Cropland, CEAP I and CEAP II
CEAP I

Nitrogen
Management
Level

Acres
(1000)

National
High
Moderately High
Moderate
Low

313,065
136,007
106,224
22,213
48,620

CEAP II

Percent
43
34
7
16

Acres
(1000)
315,303
99,850
122,954
29,220
63,279

CEAP II minus CEAP I

Percent
32
39
9
20

Acres
(1000)
2,238
-36,158
16,730
7,008
14,659

Percent
-12
5
2
5

Percent
Change in
Acres from
CEAP I
1
-27
16
32
30

Conservation Practices on Cultivated Cropland

79

Figure 52. Cultivated Cropland by Nitrogen Management Level, CEAP I and CEAP II

Production regions generally followed the national trends. All but the Southwest region
experienced declines in high nitrogen management, and nine regions experienced gains in
moderately high management. Three regions—North Central and Midwest, Northern Plains, and
Southern and Central Plains—had the largest declines in high nitrogen management at nearly 31
million acres, accounting for 86 percent of the total nationwide decline between the survey
periods. Losses in eight regions were 25 percent or more of the acres in their high nitrogen
management level in CEAP I. The Northern Plains and Southern and Central Plains led the gains
in moderately high nitrogen management, accounting for 73 percent of the total increase (fig.
53).
Nitrogen Management by Tillage System
The decline in nitrogen management between the CEAP surveys is concentrated in the
conventional and reduced tillage systems. The overall decline in high management levels came
from declines in conventionally tilled and reduced till acres, only partially offset by a slight
increase in high management in continuous no-till (table 40). While continuous no-till with high
nitrogen management increased by nearly 6 million acres, high management was a smaller share
of the tillage class in CEAP II as compared to CEAP I, 29 to 39 percent respectively. In contrast,
half (26.6 million acres) of the increase in conservation tillage systems (reduced tillage and
continuous no till) was in low and moderate nitrogen management levels.
Conventional tillage experienced declines in every nitrogen management level, reflecting the
general exodus of acres under that form of tillage (fig. 54). Reduced tillage had a decline in high
nitrogen management (nearly 9 million acres) but increases in moderately high, moderate, and
low management. Continuous no-till increased in every nitrogen management level, but like
reduced tillage the largest increases were in moderately high and low nitrogen management,
accounting for 75 percent of the total increase.

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Conservation Effects Assessment Project

Figure 53. Nitrogen Management Levels on Cultivated Cropland, CEAP I and CEAP II

Conservation Practices on Cultivated Cropland

81

Table 40. Nitrogen Management on Cultivated Cropland by Tillage System and CEAP Survey
CEAP I
Tillage System / Nitrogen
Management Level
Conventional Tillage
High
Moderately High
Moderate
Low
Reduced Tillage
High
Moderately High
Moderate
Low
Continuous No-Till
High
Moderately High
Moderate
Low
National
High
Moderately High
Moderate
Low

Acres
(1000)
155,941
69,647
48,703
9,504
28,086
95,572
42,482
31,939
8,128
13,023
61,553
23,878
25,583
4,581
7,512
313,065
136,007
106,225
22,213
48,621

CEAP II minus CEAP
I

CEAP II

Percent
50
45
31
6
18
31
44
33
9
14
20
39
42
7
12
43
34
7
16

Acres
(1000)
104,771
36,231
35,915
7,582
25,044
107,423
33,778
40,050
12,554
21,041
103,108
29,841
46,989
9,084
17,195
315,303
99,850
122,954
29,220
63,280

Percent
33
35
34
7
24
34
31
37
12
20
33
29
46
9
17
32
39
9
20

Acres
(1000)
-51,169
-33,416
-12,788
-1,922
-3,042
11,852
-8,704
8,111
4,426
8,018
41,556
5,963
21,406
4,503
9,683
2,238
-36,157
16,729
7,007
14,659

Figure 54. Nitrogen Management Level by Tillage System, CEAP II minus CEAP I

Percent
-17
-10
3
1
6
4
-13
4
3
6
13
-10
4
1
4
-12
5
2
5

Percent
Change
in Acres
from
CEAP I
-33
-48
-26
-20
-11
12
-20
25
54
62
68
25
84
98
129
1
-27
16
32
30

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Conservation Effects Assessment Project

The downward shifts in nitrogen management levels reflect the decline in incorporation of
applied nitrogen. Conversion to no-till and reduced tillage systems requires nutrient management
changes. Incorporation techniques such as injection, knifing, or banding are needed, and these
techniques may also require a different nutrient form. For example, no-till may not be an option
with existing equipment and solid forms of manure because some level of incorporation is
required.
Nitrogen Management on Vulnerable Acres
Cultivated cropland with high and moderately high soil vulnerability index ratings for leaching
(SVI-L) needs more intensive nitrogen management to reduce the potential for nitrogen losses.
Between the survey periods, the extent of cultivated cropland with high vulnerability (high SVIL) changed little (less than 1 percent), while acres with moderately high vulnerability
(moderately high SVI-L) declined by 16 percent. By CEAP II, 41 percent of cultivated cropland
was in these two vulnerability classes (table 41; appendix 2, table A-26).
Between the surveys, high nitrogen management on high and moderately high SVI-L acres
declined by over 16 million acres; a nearly 30-percent reduction for each vulnerability group
from CEAP I levels. In contrast, cultivated cropland in the riskiest combination of high and
moderately high SVI-L and low nitrogen management increased by over 4 million acres, and
most (86 percent) was high SVI-L acres. By CEAP II, 67 percent of high and moderately high
vulnerability cropland were under high or moderately high levels of nitrogen management, down
from 75 percent in CEAP I. Between the two surveys, higher levels of nitrogen management
declined on the most vulnerable acres while lower levels of nitrogen management increased (fig.
55).
Table 41. Nitrogen Management Levels by Soil Vulnerability Index Leaching, CEAP I and CEAP II
Nitrogen
Management
Level

High
Acres
(1,000s)

Percent
SVI
Acres

SVI-L Rating
Moderately High
Moderate
Percent
Percent
Acres
Acres
SVI
SVI
(1,000s)
(1,000s)
Acres
Acres

Low

National

Acres
(1,000s)

Percent
SVI
Acres

Acres
(1,000s)

CEAP I
High
37,561
Moderately High
31,637
Moderate
7,394
Low
14,921
National
91,513
CEAP II
High
26,523
Moderately High
34,158
Moderate
11,733
Low
18,867
National
91,281
CEAP II minus CEAP I
High
-11,037
Moderately High
2,521
Moderate
4,339
Low
3,945
National
-232
Change relative to CEAP I Levels
High
-11,037
Moderately High
2,521
Moderate
4,339
Low
3,945
National
-232

41
35
8
16
29

17,459
16,160
4,687
7,749
46,055

38
35
10
17
15

73,169
52,543
9,151
23,282
158,145

46
33
6
15
51

7,819
5,884
981
2,668
17,351

45
34
6
15
6

136,007
106,224
22,213
48,620
313,065

29
37
13
21
29

12,399
14,348
3,605
8,381
38,732

32
37
9
22
12

51,809
61,970
11,116
30,520
155,416

33
40
7
20
49

9,118
12,477
2,767
5,512
29,874

31
42
9
18
9

99,850
122,954
29,220
63,279
315,303

-12
3
5
4
0

-5,060
-1,812
-1,082
631
-7,323

-6
2
-1
5
-2

-21,359
9,427
1,965
7,238
-2,729

-13
7
1
5
-1

1,299
6,594
1,786
2,844
12,522

-15
8
4
3
4

-36,158
16,730
7,008
14,659
2,238

-29
8
59
26
<1

-5,060
-1,812
-1,082
631
-7,323

-29
-11
-23
8
-16

-21,359
9,427
1,965
7,238
-2,729

-29
18
21
31
-2

1,299
6,594
1,786
2,844
12,522

17
112
182
107
72

-36,158
16,730
7,008
14,659
2,238

Conservation Practices on Cultivated Cropland

83

Figure 55. Change in Nitrogen Management on Cultivated Cropland by SVI-L, CEAP II minus CEAP I

Phosphorus
Between CEAP I and CEAP II, cultivated cropland with high phosphorus management declined
by nearly 31 million acres, while moderately high management increased by 6.5 million acres;
together there was a net loss in the higher management levels of 24.5 million acres (table 42;
appendix 2, table A-24). In contrast, cultivated cropland with moderate and low phosphorus
management increased by 26.7 million acres. While most cultivated cropland (75 percent)
remained in high and moderately high phosphorus management in CEAP II, it was down from 83
percent in CEAP I, reflecting the overall decline in nutrient management practices between the
surveys.
By CEAP II, cultivated cropland with high phosphorus management decreased by 15 percent
from CEAP I levels. Acres in the remaining three management levels increased between 14 and
53 percent (fig. 56).
Table 42. Phosphorus Management Levels on Cultivated Cropland, CEAP I and CEAP II
Management
Level
National
High
Moderately High
Moderate
Low

CEAP I
Acres
(1000)
313,065
212,703
47,086
37,130
16,146

CEAP II

Percent
68
15
12
5

Acres
(1000)
315,303
181,711
53,549
56,902
23,140

CEAP II minus CEAP I

Percent
58
17
18
7

Acres
(1000)
2,238
-30,992
6,463
19,772
6,994

Percent
-10
2
6
2

Percent
Change in
Acres from
CEAP I
1
-15
14
53
43

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Conservation Effects Assessment Project

Figure 56. Cultivated Cropland by Phosphorus Management Level, CEAP I and CEAP II

While six regions each had more than 1 million acres exit from high management, two regions—
North Central and Midwest and Southern and Central Plains—accounted for most of the loss
(fig. 57). Together these regions accounted for 65 percent of the total decline in cultivated
cropland with a high level of phosphorus management (23.1 million acres) and 65 percent of the
total increase in cultivated cropland with low phosphorus management (4.5 million acres).
Phosphorus Management by Tillage System
The changes in tillage between the CEAP surveys are reflected in the changes in phosphorus
management levels on cultivated cropland. The overall decline in high management levels came
from declines in conventional tillage and reduced till acres, only partially offset by the increase
in high management in continuous no-till (table 43). While continuous no-till with high
phosphorus management increased by 18.1 million acres, it occupied a smaller share of the
tillage class in CEAP II as compared to CEAP I, dropping from 59 percent to 53 percent between
the two surveys. In contrast, nearly 54 percent (28.7 million acres) of the increase in
conservation tillage systems (reduced tillage and continuous no-till) was in low and moderate
nitrogen management levels.
Conventionally tilled acres experienced declines in every phosphorus management level,
reflecting the general exodus of acres under that form of tillage (fig. 58). Phosphorus
management levels improved on nearly 12 million reduced tillage acres as the decline in high
phosphorus management (4.1 million acres) was offset by large gains in moderate (8.4 million
acres), moderately high (6.4 million acres), and low (4.3 million acres) management levels.
Continuous no-till increased by over 41.5 million acres and in every phosphorus management
level, but unlike reduced tillage the largest increase was in high phosphorus management (18.2
million acres), accounting for 44 percent of the total.

Conservation Practices on Cultivated Cropland
Figure 57. Phosphorus Management on Cultivated Cropland by Region, CEAP I and CEAP II

85

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Conservation Effects Assessment Project

Table 43. Phosphorus Management on Cultivated Cropland by Tillage System and CEAP Survey
Tillage System /
Phosphorus
Management Level
Conventional Tillage
High
Moderately High
Moderate
Low
Reduced Tillage
High
Moderately High
Moderate
Low
Continuous No Till
High
Moderately High
Moderate
Low
National
High
Moderately High
Moderate
Low

CEAP I
Acres
(1000)
155,941
112,525
18,463
15,194
9,759
95,572
63,827
15,022
12,900
3,823
61,553
36,351
13,601
9,036
2,564
313,065
212,703
47,086
37,130
16,146

CEAP II minus CEAP
I

CEAP II

Percent
50
72
12
10
6
31
67
16
13
4
20
59
22
15
4
68
15
12
5

Acres
(1000)
104,771
67,498
14,282
13,828
9,162
107,423
59,706
19,225
21,333
7,160
103,108
54,507
20,042
21,741
6,819
315,303
181,711
53,549
56,902
23,141

Percent
33
64
14
13
9
34
56
18
20
7
33
53
19
21
7
58
17
18
7

Acres
(1000)
-51,170
-45,027
-4,181
-1,365
-597
11,851
-4,121
4,203
8,433
3,337
41,555
18,156
6,441
12,705
4,255
2,238
-30,992
6,463
19,773
6,995

-17
-8
2
3
2
4
-11
2
6
3
13
-6
-3
6
2

Percent
Change
in Acres
from
CEAP I
-33
-40
-23
-9
-6
12
-6
28
65
87
68
50
47
141
166

-10
2
6
2

-15
14
53
43

Percent

Figure 58. Cultivated Cropland by Phosphorus Management Level and Tillage System, CEAP II minus
CEAP I

Conservation Practices on Cultivated Cropland

87

Phosphorus Management on Vulnerable Acres
Cultivated cropland with high and moderately high soil vulnerability index ratings for runoff
(SVI-R) need more intensive management to reduce the potential for phosphorus losses.
Between the survey periods, the extent of cultivated cropland with high vulnerability (high SVIR) increased by 6.4 million acres (24 percent from CEAP I levels) and acres with moderately
high vulnerability (moderately high SVI-R) increased by 4.4 million acres (8 percent from CEAP
I levels) (table 44; appendix 2, table A-27). By CEAP II, 29 percent of cultivated cropland were
in these two high vulnerability classes.
Between the surveys, high phosphorus management on high and moderately high SVI-R acres
declined by nearly 3 million acres (3- and 7-percent reductions from CEAP I levels,
respectively). In contrast, cultivated cropland in the riskiest combination of high and moderately
high SVI-R and low phosphorus management increased by over 2.7 million acres. By CEAP II,
69 percent of high and moderately high vulnerability acres were under high or moderately high
levels of phosphorus management, down from 79 percent in CEAP I. Between the two surveys,
higher levels of phosphorus management declined on the most vulnerable acres while lower
levels of phosphorus management increased (fig. 59).
Table 44. Phosphorus Management on Cultivated Cropland by Soil Vulnerability Index Runoff (SVI-R)
Rating, CEAP I and CEAP II
Phosphorus
Management
Level

SVI R Rating
National
High
Moderately High
Moderate
Low
Acres
Percent
Acres
Percent
Acres
Percent
Acres
Percent
Acres
(1,000s) SVI Acres (1,000s) SVI Acres (1,000s) SVI Acres (1,000s) SVI Acres (1,000s)

CEAP I
High
16,656
Moderately High
3,997
Moderate
4,601
Low
1,890
National
27,145
CEAP II
High
16,227
Moderately High
5,286
Moderate
9,125
Low
2,895
National
33,532
CEAP II minus CEAP I
High
-429
Moderately High
1,288
Moderate
4,523
Low
1,005
National
6,387
Change Relative to CEAP I
High
-429
Moderately High
1,288
Moderate
4,523
Low
1,005
National
6,387

61
15
17
7
9

35,159
7,980
7,454
3,128
53,721

65
15
14
6
17

37,269
9,043
6,224
1,999
54,534

68
17
11
4
17

123,619
26,066
18,851
9,129
177,665

70
15
11
5
57

212,703
47,086
37,130
16,146
313,065

48
16
27
9
11

32,670
8,869
11,750
4,877
58,165

56
15
20
8
18

26,158
7,975
7,319
3,330
44,781

58
18
16
7
14

106,657
31,420
28,710
12,039
178,825

60
18
16
7
57

181,711
53,549
56,902
23,140
315,303

-13
1
10
2
2

-2,489
889
4,295
1,749
4,444

-9
0
6
3
1

-11,111
-1,068
1,095
1,331
-9,753

-10
1
5
4
-3

-16,962
5,354
9,859
2,910
1,161

-10
3
5
2
0

-30,992
6,463
19,773
6,994
2,238

-3
32
98
53
24

-2,489
889
4,295
1,749
4,444

-7
11
58
56
8

-11,111
-1,068
1,095
1,331
-9,753

-30
-12
18
67
-18

-16,962
5,354
9,859
2,910
1,161

-14
21
52
32
1

-30,992
6,463
19,773
6,994
2,238

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Conservation Effects Assessment Project

Figure 59. Change in Phosphorus Management on Cultivated Cropland by SVI-R, CEAP II minus CEAP I

Conservation Practices on Cultivated Cropland

89

HOW DID THE CONSERVATION CONDITION IN THE CEAP SURVEYS
COMPARE TO ALTERNATIVE TREATMENT LEVELS?
Alternative treatment levels were created to simulate the potential benefits from additional
conservation and the possible tradeoffs in crop productivity or through unintended effects on
related resource concerns. The estimated loss reductions associated with alternative treatment
levels were modeled for all cultivated cropland acres irrespective of conservation treatment need.
Estimates for treating all acres may overstate potential benefits since they include additional
reductions from acres meeting resource concern thresholds, which would be unlikely to receive
additional conservation treatment, or the benefit of additional conservation would be small.
However, comparison of the alternative treatment levels with CEAP I and CEAP II conservation
conditions provide valuable context for understanding existing conservation benefits.
The Erosion Control (EC) and Nutrient Management (NM) treatment levels simulate parts of a
comprehensive plan that addresses the natural resource concerns of the agricultural system. The
EC is primarily the addition of structural practices designed to control and trap losses from
cropped fields, while the NM addresses nutrient application method, form, timing, and a 10percent reduction in application rate and is designed to avoid excess surface and subsurface
nutrient losses.28 The Erosion Control and Nutrient Management (ENM) level combines these
two treatments to simulate a comprehensive plan with improvements to structural conservation
practices and nutrient management. The ENM is also modeled with only 85 percent of the
nutrient form being applied (ENM85) plus timing and incorporation adjustments and runoff
control to improve nutrient-use efficiency.
While the EC treatment level would control runoff and reduce surface losses that benefit yield, it
would also encourage infiltration, which can increase subsurface nitrogen losses. Under the NM
treatment level, the lack of runoff control could increase surface nitrogen, sediment, and total
phosphorus losses. Without the EC runoff control, the NM rate reduction would fail to achieve
its purpose of reducing nutrient losses and could negatively affect yield. Thus, the ENM
treatment level reflects how EC runoff control would support NM reduced nutrient application
rates, contributing to production and conservation of soil and nutrient inputs. The treatment
levels demonstrate the benefits of a systems approach that considers multiple resource concerns
in a conservation treatment.

Erosion Control and Nutrient Management (ENM)
Under ENM, structural and nutrient management practices are combined to address all
applicable resource concerns while maintaining or enhancing productivity as compared to NM
alone. At the ENM treatment level, all regions would have 87 percent or more of their cultivated
cropland meeting the thresholds for sediment, wind erosion, surface nitrogen, and total
phosphorus resource concerns (table 45).29
At a 10-percent reduction, productivity is maintained on most soils while demonstrating the effects of improved use
efficiency that is provided through rate reductions in combination with improved timing and application methods, particularly
in precision agriculture systems.
29 Wind erosion control under ENM reflects the application of structural wind erosion control practices on the most susceptible
acres, however, these are not widely adopted in the most wind-erosion-prone regions where water supply challenges the use
28

90

Conservation Effects Assessment Project

Table 45. Estimated Percent of Cultivated Cropland Acres Meeting Resource Concern Thresholds under
ENM, by Region
Resource Concern
Sheet
Geographic Area
Wind Surface Subsurface Total Soluble
Soil
Sediment
and
P
**
N
N
P
Carbon
Rill
97
93
100
99
77
97
79
87
National ENM
Region
Percent Regional Acres
Atlantic and Gulf
97
91
100
99
47
94
39
83
Coastal Plains
California Coastal
99
100
100
100
74
98
86
60
East Central
91
75
100
97
60
89
39
87
Lower Mississippi
91
86
100
98
64
87
26
87
and Texas Gulf Coast
North Central and
97
90
100
99
75
97
78
88
Midwest
Northeast
95
81
100
99
57
88
49
82
Northern Plains
100
100
100
100
83
100
99
86
Northwest
99
100
100
100
85
99
95
91
South Central
88
80
100
94
65
89
55
72
Southern and Central
100
99
100
100
92
100
99
92
Plains
Southwest
97
97
100
100
79
97
94
82
* The highlighted cells indicate a regional percentage equal to or above the national average.
** Wind erosion control under ENM reflects the application of structural wind erosion control practices on the
most susceptible acres, however, these are not widely adopted in the most wind-erosion prone regions where water
supply challenges the use of vegetative structural practices. CEAP survey data indicate that only 2 percent of acres
had structural wind erosion control practices applied, highlighting the need for alternative wind erosion control
methods

Subsurface nitrogen and soluble phosphorus losses are the most challenging to control, even
under ENM. While surface losses can be trapped by edge-of-field practices (e.g., filter strips and
buffers), there are fewer trapping options for subsurface and soluble losses. Treating the cropped
areas with nutrient management and improved runoff control has limitations, especially in higher
rainfall regions and with the economic and social priorities for food, feed, fiber, and fuel from
cropland. Enhanced-efficiency fertilizers and precision agriculture with variable-rate technology
can help, along with improved timing of nutrient applications. In some cases, however, practices
such as drainage water management, establishment of wetlands or retention basins, or other
measures may be needed to prevent losses.
The percentage of cultivated cropland acres meeting the various thresholds under ENM would
vary more widely by region for sheet and rill erosion, subsurface nitrogen, soluble phosphorus,
and soil carbon. In the East Central, South Central, and Northeast regions—with higher
proportions of rolling to hilly landscapes under cultivation and rainfall above 35 inches—each
would have 80 percent or less of cultivated cropland meeting the sheet and rill erosion threshold
under ENM.

of vegetative structural practices. CEAP survey data indicate that only 2 percent of acres had structural wind erosion control
practices applied, highlighting the need for alternative wind erosion control methods.

Conservation Practices on Cultivated Cropland

91

For subsurface nitrogen, seven regions would be below the national average of 77 percent and
three regions (Atlantic and Gulf Coastal Plains, East Central, and Northeast) would have 60
percent or fewer acres meeting the threshold. Six regions would be below the national average of
cultivated cropland meeting the soluble phosphorus threshold of 79 percent. The Lower
Mississippi and Texas Gulf Coastal Plains was the most challenged, with its humid, subtropical
climate, tile drainage, and rolling hills adjacent to flood plains.
Acres not meeting thresholds under the substantial conservation modeled in ENM are typically
on the most vulnerable landscapes and may need additional conservation such as cover crops or
other changes to the rotation, possibly including perennials, to meet thresholds.

Comparing Change in Cultivated Cropland Conservation Treatment Levels in
CEAP Surveys
Cultivated cropland acres were categorized by conservation treatment levels to allow
comparisons of change between the two CEAP surveys. The treatment levels were based on the
number of resource concerns where established loss thresholds were being met. At the high
treatment level, thresholds were met for all eight resource concerns (sheet and rill erosion, wind
erosion, sediment, surface nitrogen, subsurface nitrogen, total phosphorus, soluble phosphorus,
and soil carbon). At the moderate treatment level, thresholds were met for five to seven of the
resource concerns, and at the low treatment level, thresholds were met for four or fewer resource
concerns.
Between the two CEAP surveys, there was no change in the percentage of cultivated cropland in
each of the treatment levels nationally (table 46), although the mix of resource concern
thresholds being met could have shifted in some regions. For example, more acres were meeting
erosion and sediment thresholds in CEAP II, offsetting a decline in acres meeting subsurface
nitrogen and soluble phosphorus thresholds. At the regional scale, there were a few significant
changes, most notably in the Northwest, Southwest, and Southern and Central Plains, where
cultivated cropland with high treatment levels increased by 9 to 14 percent.
Eight regions had declines in cultivated cropland meeting high treatment levels from CEAP I to
CEAP II, likely due to a loss in meeting certain nutrient management thresholds. The South
Central region dropped from 30 percent to 21 percent of acres in high treatment and increased
from 26 percent to 30 percent in low treatment levels. The East Central region dropped from 19
percent to 11 percent of acres in high treatment levels, and the Lower Mississippi and Texas Gulf
Coast had the fewest acres in high treatment, dropping from 11 percent to 9 percent between the
CEAP surveys. Meeting the high treatment level was challenging in these higher rainfall regions.
Except for the Northeast, South Central, and Northwest, most regions had little change in the
percentage of acres with low treatment levels. Most regions showed an increase in the moderate
treatment level, with seven regions experiencing an increase. Notably, the Northwest and
Southern and Central Plains had high treatment levels on over 60 percent of cultivated cropland
by CEAP II. The Northern Plains followed at 56 percent but had declined relative to CEAP I
levels.

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Conservation Effects Assessment Project

Table 46. Cultivated Cropland by Conservation Treatment Level, CEAP I and CEAP II
Conservation Treatment Level
High
Moderate
Low
Geographic Scope
CEAP I CEAP II CEAP I CEAP II CEAP I CEAP II
Percent
National
43
43
47
47
10
10
Region
Atlantic and Gulf Coastal Plains
15
13
70
73
15
13
California Coastal
45
40
52
58
3
2
East Central
19
11
56
63
25
26
Lower Mississippi and Texas Gulf Coast
13
9
68
72
19
18
North Central and Midwest
43
40
47
51
10
9
Northeast
15
15
55
63
30
22
Northern Plains
58
56
38
36
5
8
Northwest
47
61
47
36
6
3
South Central
30
21
44
49
26
30
Southern and Central Plains
55
64
40
32
5
4
Southwest
31
44
64
50
6
5
* The highlighted cells indicate that CEAP II values are higher than CEAP I.

Comprehensive conservation systems that address all applicable resource concerns can achieve
significant control of potential losses from farm fields (table 47). The 43 percent of cultivated
cropland acres with high treatment met thresholds for all eight resource concerns, while the 10
percent of acres at low treatment met none. Moderate levels of treatment met all but subsurface
nitrogen and soluble phosphorus thresholds. In fact, the subsurface nitrogen losses of 33 lbs/a/y
losses were very near that of low treatment (39 lbs/a/y). Soluble phosphorus had an average of
0.6 lbs/a/y, just barely over the threshold. Both resource concerns, however, had the lowest
national performance under the ENM treatment at only 77 and 79 percent, respectively,
indicating the difficulty in controlling these loss pathways.
Table 47. Losses on Cultivated Cropland by Treatment Level and Resource Concern, CEAP II
Percent Cultivated
Sediment
Cropland Acres
Treatment
CEAP I CEAP II
tons
Level
High
Moderate
Low

43
47
10

43
47
10

Loss Threshold (ac/yr)

Subsurface
N
lbs

0.2
0.5
5.1

7.2
33.1
39.7

2

25

Surface Total Soluble
Water
N
P
P
Erosion
lbs
lbs
lbs
tons
unit / per acre / per year
3.0
0.5
0.1
0.7
5.9
1.7
0.6
1.3
25.8
8.2
1.2
7.5
15

3

0.5

Soil T

Wind
Erosion
tons

Soil
Carbon
lbs

0.9
1.8
4.0

322.1
161.7
-174.1
Gain or
Maintain

Soil T

* The highlighted cells indicate that loss meets the threshold for that resource concern.

Erosion Control and Nutrient Management Treatment (ENM) Effects by
Treatment Need
Simulations that applied ENM to cultivated cropland needing conservation treatment show the
benefits of conservation systems that address all applicable resource concerns. In CEAP II, over
30 million acres (10 percent) of cultivated cropland were in the low conservation treatment level
(meeting thresholds for four or fewer resource concerns) and thus considered high-need acres.
Moderate-need acres (those meeting thresholds for five to seven resource concerns) accounted
for another 148.8 million acres (47 percent).

Conservation Practices on Cultivated Cropland

93

Treating high-need acres to the ENM level would reduce sediment loss by 44 percent, largely
through runoff control, which would also reduce surface nitrogen losses by 28 percent and total
phosphorus losses by 29 percent. As expected, however, this treatment level would reduce
subsurface nitrogen and soluble phosphorus losses by only 3 and 4 percent, respectively (table
48).
Table 48. Estimated Loss Reduction from CEAP II Baseline, by Loss Type and Treatment Level
Treatment Level
CEAP II
High-and ModerateBaseline Loss
Loss Type
High Need Acres
All Acres
Need Acres
Tons
Percent Reduction
Sediment
263,455
44
61
67
Wind Erosion
509,740
22
72
93
Sheet and Rill Erosion
522,263
17
23
24
Surface Nitrogen
1,038
28
60
74
Subsurface Nitrogen
3,550
3
19
21
Total Phosphorus
283
29
52
58
Soluble Phosphorus
70
4
13
15
Soil Carbon
31,381
4
3
0
Acres in category (1,000s)
30,073
178,855
315,303

Treating the high- and moderate-need acres to the ENM level would reduce most losses to levels
near what could be achieved if all acres were treated. For some resource concerns (i.e., sheet and
rill erosion, subsurface nitrogen, soluble phosphorus, carbon), however, reductions would be
relatively small. In addition, because the low-need acres (high conservation treatment level) meet
all resource concern loss thresholds, increased treatment can risk affecting productivity. Both
results highlight the need for additional measures beyond ENM to increase control of subsurface
nitrogen and soluble phosphorus losses.
The reduction in nutrient application rates and attention to application timing and method
supported by erosion-control practices would result in significant loss reductions in the hightreatment-needs acres (table 49). Sediment, wind erosion, surface nitrogen, total phosphorus, and
soil carbon would all improve by more than 50 percent. Sheet and rill erosion would be reduced
by nearly 3 t/a/y—a 39-percent reduction—while the two most difficult resource concerns to
control, losses of subsurface nitrogen and soluble phosphorus, would be reduced by 16 and 15
percent, respectively. In addition, estimated average yields of the five most prevalent crops were
negligibly affected in this treatment simulation. The high-needs acres would see a slight but not
significant increase in production, while the other treatment groups would experience very small
decreases.
Notably, ENM treatment would result in a significant reduction in nitrogen and phosphorus
applications, producing an associated economic benefit for the farm. Treating the high-need
acres would reduce nitrogen applied by nearly 16 lbs/a/y and phosphorus by over 5 lbs/a/y.
Likewise, treating moderate-need acres would reduce nitrogen applied by over 14 lbs/a/y and
phosphorus by over 4 lbs/a/y. The focused treatment of high- and moderate-needs acres within a
crop field highlight the economic and environmental opportunities of comprehensive
conservation planning and precision conservation.

94

Conservation Effects Assessment Project

Table 49. Estimated Effects of ENM Treatment on Cultivated Cropland by Resource Concern and Treatment
Need
Treatment Need
High Need
Moderate Need
Low Need
Change
Change
Change
Resource Concerns
CEAP II
As
CEAP II
As
CEAP II
As
from
from
from
Baseline Treated
Baseline Treated
Baseline Treated
CEAP II
CEAP II
CEAP II
unit/ac/yr
Percent
unit/ac/yr
Percent
unit/ac/yr
Percent
Sediment (tons)
5.1
1.2
-76
0.5
0.2
-55
0.2
0.1
-50
Sheet and Rill Erosion
7.5
4.6
-39
1.3
1.1
-15
0.7
0.7
-6
(tons)
Wind Erosion (tons)
4.0
0.2
-95
1.8
0.1
-93
0.9
0.1
-89
Surface Nitrogen (lbs.)
25.8
6.5
-75
5.9
1.5
-74
3.0
0.9
-71
Subsurface Nitrogen
39.8
33.3
-16
33.1
25.2
-24
7.2
6.3
-12
(lbs.)
Total Phosphorus (lbs.)
8.2
2.6
-68
1.7
0.8
-52
0.5
0.3
-49
Soluble Phosphorus
1.2
1.0
-15
0.6
0.5
-15
0.1
0.1
-17
(lbs.)
Soil Carbon (tons)
-174.2
-82.0
-53
161.7
154.7
-4
322.2
308.7
-4
Estimated Input Effect (lbs/a/y)
Nitrogen Applied (lbs.)
92.7
76.7
-17
89.0
74.5
-16
63.4
58.7
-7
Phosphorus Applied
24.2
18.6
-23
21.3
17.0
-20
15.1
14.0
-7
(lbs.)
Estimated Yield Effect (bu/a/y)
Corn (Grain)
158.3
158.8
0.3
159.5
158.1
-0.9
158.3
155.8
-1.6
Cotton
912.9
914.0
0.1
888.9
877.7
-1.3
896.8
883.2
-1.5
Durum & Spring Wheat
54.9
54.9
0.1
53.1
52.7
-0.7
48.7
48.6
-0.2
Soybeans
43.8
43.9
0.2
42.9
42.6
-0.8
43.9
43.5
-0.7
Winter Wheat
59.8
60.2
0.7
56.7
55.5
-2.1
42.3
42.2
-0.1

How Did Conservation in CEAP I and CEAP II Compare to ENM?
The conservation measures in place by CEAP II delivered progress toward the simulated ENM
treatment level for most resource concerns (table 50). By CEAP II, sediment and sheet and rill
erosion losses were at 80 and 84 percent of the simulated ENM treatment level, both with
increases over the decade. While surface and subsurface nitrogen and sediment-transported
phosphorus were at 61, 67, and 65 percent of their respective ENM treatment levels, subsurface
nitrogen losses had increased since CEAP I. In CEAP II, soluble phosphorus losses were at 54
percent of ENM treatment level, down significantly from CEAP I. Wind erosion, while only at
42 percent of its ENM treatment level, nevertheless had the greatest progress toward ENM
between the two CEAP surveys.

Conservation Practices on Cultivated Cropland

95

Table 50. Progress toward ENM by Resource Concern, CEAP I and CEAP II
Treatment Level
Resource Concern

No
Practice
(NP)

Sheet & Rill Erosion (Losses)
Wind Erosion (Losses)
Sediment (Losses)
Surface N (Losses)
Subsurface N (Losses)
Total P (Losses)
Soluble Phosphorus (Losses)
Soil Carbon (Gains)

1,197,255
848,310
946,467
2,218
5,095
592
83
6,823

Erosion
Control and
CEAP
CEAP
Nutrient
I
II
Management
(ENM)
Average Annual Tons (1,000s)
398,231
598,623 522,263
37,024
603,605 509,740
87,834
337,635
263,455
272
1,073
1,038
2,803
3,130
3,550
118
290
283
59
63
70
31,320
22,519
31,381

Progress toward ENM

CEAP
II
minus
CEAP
I

Change in
Tons
Relative to
CEAP I

76,360
93,865
74,181
-35
420
-7
7
8,862

13
16
22
-3
13
-2
11
39

CEAP
I
Percent
75
30
71
59
86
64
85
64

CEAP
II

CEAP
II
minus
CEAP I

84
42
80
61
67
65
54
100

9
12
11
2
-18
1
-31
36

Erosion and Sediment
With the increase in conservation tillage, structural practices, cover crops, and high-biomass
conservation crop rotations between the CEAP surveys, there was significant progress toward
ENM for sheet and rill erosion, wind erosion, and sediment. In CEAP II, annual sheet and rill
erosion was about 84 percent of ENM, up from 75 percent in CEAP I (fig. 60). Sediment was at
80 percent of ENM in CEAP II, up from 71 percent in CEAP I. Although progress for wind
erosion was only 42 percent of ENM in CEAP II, it was up from 30 percent in CEAP I. The
lower performance level reflects that much of the current toolbox for wind erosion control
depends on vegetative practices that are typically less well suited to the most wind-erosion-prone
areas of the Nation.
Two regions—North Central and Midwest and Southern and Central Plains—were above the
average national progress toward the sheet and rill ENM, at 90 percent and 86 percent,
respectively. The Northern Plains region led progress toward the wind erosion ENM at 58
percent, 16 percentage points above the national average. Progress toward the sediment ENM
mirrored sheet and rill erosion, with the North Central and Midwest and Southern and Central
Plains regions being above the national average, at 86 percent and 81 percent respectively (fig.
61).

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Figure 60. Erosion and Sediment Progress Toward ENM, CEAP I and CEAP II

Figure 61. Progress toward Erosion and Sediment ENM by Loss Pathway and Region, CEAP II

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Nitrogen
Progress toward ENM for the nitrogen-related resource concerns was mixed, reflecting the
increase in conservation measures that controlled runoff and the general decline in nutrient
management practices between the CEAP surveys (fig. 62). The surface nitrogen resource
concern was at 61 percent of ENM performance in CEAP II, up only slightly from 59 percent in
CEAP I. However, it was the only nitrogen loss pathway that increased in progress toward ENM
treatment level between the two survey periods. Control of subsurface nitrogen losses
experienced a significant decline in progress toward ENM, dropping from 86 percent in CEAP I
to 67 percent in CEAP II, consistent with the decline in nutrient management practices,
particularly the decline in nutrient incorporation.
Figure 62. Surface and Subsurface Nitrogen Progress Toward ENM, CEAP I and CEAP II

Over the decade between surveys, five of the 11 regions had increases in total nitrogen losses,
led by the Northern Plains with a 49-percent increase, followed by the East Central (32 percent)
and North Central and Midwest (13 percent). Two regions—the North Central and Midwest and
Northern Plains—had the greatest increase in nitrogen losses, but also had progress toward ENM
above the 64-percent national average, at 70 and 67 percent, respectively.
Progress toward the surface nitrogen ENM was led by the North Central and Midwest and East
Central regions, at 74-percent and 64-percent progress, respectively. The Northern Plains region
led progress toward the subsurface ENM at 84 percent, 16 percentage points above the national
average. Only two regions (Northwest and South Central) performed better in CEAP II than
CEAP I relative to the ENM for all three measures (fig. 63).

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Figure 63. Progress toward Nitrogen ENM by Loss Pathway and Region, CEAP II

Phosphorus
Like nitrogen, phosphorus resource concerns also experienced mixed progress toward ENM,
reflecting the change in conservation adoption over the decade (fig. 64). The total phosphorus
resource concern made progress, reaching 65 percent of ENM by CEAP II, up from 64 percent in
CEAP I. In contrast, soluble phosphorus progress toward ENM was at 54 percent in CEAP II,
down from 85 percent in CEAP I and experiencing the largest percentage decline of all resource
concerns, reflecting increased application rates and the declines in nutrient incorporation. The
progress for total phosphorus was affected by the soluble decline, tempering its performance. In
comparison, for sediment-transported phosphorus (discussed elsewhere in the report) progress
toward ENM increased from 63 percent to 66 percent in CEAP I and CEAP II, respectively.
Figure 64. Total and Soluble Phosphorus Progress toward ENM, CEAP I and CEAP II

Nearly every region gained in progress toward the total phosphorus ENM between the two
surveys, while only one region—North Central and Midwest—was above the average national
progress. The North Central and Midwest was also the only region above the national average for
the sediment-transported ENM, at 74 percent, the same as the region’s CEAP I progress. The

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99

California Coastal and Lower Mississippi and Texas Gulf Coast regions led progress toward the
soluble phosphorus ENM at 77 and 73 percent, respectively (fig. 65).
Figure 65. Progress toward Phosphorus ENM by Loss Pathway and Region, CEAP II

Soil Carbon
Soil carbon is evaluated in terms of carbon maintained or gained rather than a reduction in
losses. In CEAP II, soil carbon was the only resource concern achieving 100 percent of the ENM
treatment level, up from 64 percent in CEAP I and reflecting the significant increase in
conservation tillage and structural practices that retained organic matter on farm fields (fig. 66).
With the ENM treatment, the reduced nutrient application rate may result in lower biomass
production on some acres and lower the net change in carbon. In a comprehensive plan, soil
carbon may not be able to be maximized on all acres if other resource concerns such as water
quality are priorities.
Figure 66. Soil Carbon Progress toward ENM, CEAP I and CEAP II

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All but one region (South Central) gained in progress toward the soil carbon ENM between the
two surveys, and four regions—Atlantic and Gulf Coastal Plains, East Central, North Central and
Midwest, and Northeast—were above the national average of 100 percent. Although progress in
the drier regions of California Coastal and Southwest trailed other regions, each had among the
largest increases between the survey periods at 163 and 155 percent, respectively (fig. 67).
Figure 67. Progress toward Soil Carbon ENM by Region, CEAP II

Summary
Between the CEAP surveys, most resource concerns made progress toward ENM performance
levels with two notable exceptions—subsurface nitrogen and soluble phosphorus. Both resource
concerns experienced the effects of a decline in nutrient management practices, in some areas
amplified by the adoption of conservation practices that managed runoff and related losses but
promoted infiltration and soluble losses. Nevertheless, despite setbacks in CEAP II, all but two
of the eight resource concerns were at 60 percent or more of their respective ENM levels. One of
the two with lower performance, wind erosion, faces challenges related to the scant toolbox for
controlling the loss pathway. Also, all but two resource concerns had moved closer to ENM
levels between the CEAP surveys. The decline in subsurface nitrogen and soluble phosphorus
resource concerns underscores the importance of conservation planning that considers all
applicable resource concerns to build on progress and prevent unintended consequences.

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SUMMARY AND AGENCY ACTIONS
The CEAP II report (2013–16) reveals progress from the time of the first CEAP report (2003–
06) in addressing resource concerns such as sediment loss, soil erosion, and water use. Farmer
adoption of structural practices and conservation tillage, alone or in combination, increased by
nearly 42 million acres nationwide between the two CEAP surveys. The greatest gains were
made in the adoption of structural practices plus conservation tillage, evidence that farmers were
increasingly integrating multiple conservation treatments to achieve improved results. As a
result, sheet and rill erosion dropped by nearly 70 million tons per year (an 11-percent reduction
relative to CEAP I) and wind erosion dropped by 94 million tons per year (a 15-percent
reduction relative to CEAP I). Irrigators gained efficiencies, reducing per-acre application rates
and national withdrawals over the decade.
However, the new findings also indicate some declines in nutrient management levels on
working lands. Changes in commodity prices, climate factors, and evolving technology have
driven shifts in cropping patterns in many areas toward corn and soybeans and away from wheat.
Corn and soybeans have significantly higher average nutrient needs than wheat, explaining some
of the increase in nutrient application rates between the CEAP surveys. Nutrient incorporation
declined, and consequently the shifts in rate, timing, and method of nutrient application resulted
in overall increases in subsurface nitrogen and soluble phosphorus losses over the decade.
Without attention to appropriate timing and method, increased application rates are less effective
in improving production and may even lead to reduced yields. While most cultivated cropland
acres met the various soil and nutrient loss thresholds in both survey periods, most of the related
material losses come from the small number of cultivated cropland acres that exceeded those loss
thresholds.
Since 2016, NRCS has made considerable strides in addressing key resource challenges as
presented in this report. In addition, the agency has developed new tools, such as the
Conservation Assessment Ranking Tool and Conservation Desktop, and implemented new
initiatives and program opportunities, including the National Water Quality Initiative, and
Regional Conservation Partnership Program.
In response to these new CEAP II findings, and building upon post-2016 progress, NRCS has
renewed its focus on proper nutrient and manure management, as well as an agencywide
commitment to targeted solutions to further improve the Nation’s water quality. NRCS formed
interdisciplinary teams to develop recommendations and assist with the agency’s strategy for
integrating CEAP II findings into policies, programs, and targeted initiatives that will result in
greater conservation outcomes. Each team focused on a core discipline: conservation planning
and program implementation, technical infrastructure, future resource assessment, and policy.

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The four overarching goals of our evolving nutrient management strategy are: developing a
nutrient management campaign to educate and engage partners; revitalizing the agency’s nutrient
management planning and implementation processes; focusing technical assistance on integrated
conservation planning; and enhancing program implementation with a nutrient management
focus. Each overarching goal contains a set of specific recommendations that will help NRCS
and producers continue to adapt nutrient management to national changes in markets, trade,
climate, and cropping systems.

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APPENDIX 1. OVERVIEW OF THE CEAP SAMPLING AND MODELING
APPROACH
The CEAP Cropland National Assessment is a collaborative effort led by NRCS in partnership
with USDA's Agricultural Research Service and Texas A&M University’s Texas Agri-Life
Research Center in Temple, TX. In addition, USDA's National Agricultural Statistics Service
and Farm Service Agency provide important data collection and related contributions.
CEAP uses a sampling and modeling approach that integrates natural resource and farmer survey
data with modeling to quantify the effects of commonly used conservation practices on
cultivated cropland. CEAP defines cultivated cropland as land in row crops or close-grown
crops, hay and pasture in rotation with row crops and close-grown crops, and land in long-term
conserving cover, such as land enrolled in the Conservation Reserve Program general signup.
Cultivated cropland does not include agricultural land that has been in hay, pasture, or
horticulture for four or more consecutive years.
CEAP Statistical Sampling and Modeling Approach to Simulate Conservation Practice
Effects

The CEAP Cropland sampling and modeling approach captures the diversity of land use, soils,
climate, and topography; accounts for site-specific farming activities; estimates the loss of
materials at the field scale where the science is most developed; and provides a statistical basis
for aggregating results to the national and regional levels. The approach consists of four
components:
● Sampling – A subset of National Resources Inventory (NRI) sample points serves as
“representative fields.” These NRI sample points, which are located on cultivated cropland
and land in long-term conserving cover, provide the statistical framework for the model as
well as information on soils, climate, and topography. Nationally, the CEAP sample consists
of about 18,700 points representing cropped acres. The CEAP sample was designed to allow
reporting of results at a 4-digit watershed scale (4-digit hydrologic unit code [HUCs]). The

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sample size is too small, in most cases, for reliable and defensible reporting of results for
areas below this level. CEAP cropland modeling results are reported as estimates because of
the uncertainty associated with the statistical sample.
● Farmer Surveys – The CEAP Cropland Farmer Surveys are used to collect information
needed at the selected NRI sample points to run field-level models and assess the effects of
conservation practices. NASS partners with state departments of agriculture to interview
farmers to obtain current information on farming practices, including:
o field characteristics, such as proximity to a water body or wetland and presence of tile
or surface drainage systems;
o conservation practices associated with the field;
o crop rotation plan;
o application of commercial fertilizers (rate, timing, method, and form) for crops grown
in the previous 3 years;
o application of manure (source and type, consistency, application rate, method, and
timing) on the field over the previous 3 years;
o application of pesticides (chemical, rate, timing, and method) for the previous 3
years;
o pest management practices;
o irrigation practices (system type, amount, and frequency);
o timing and equipment used for all field operations (tillage, planting, cultivation,
harvesting) over the previous 3 years, and;
o general characteristics of the operator and the operation.
Farmer participation is voluntary, and the information is confidential. Because of the large
size of the sample, the data collection process occurs over multiple years, from 2003 through
2006 for CEAP I and 2013 through 2016 for CEAP II. 30 The final CEAP samples for each
survey period were constructed by pooling the set of usable, completed surveys from all
years.
● The Physical Process Model – The Agricultural Policy Environmental Extender (APEX) is
used to assess the field-level effects of conservation practices. APEX simulates day-to-day
farming activities, wind and water erosion, the loss or gain of soil organic carbon, and edgeof-field losses of soil, nutrients, and pesticides.
● Watershed Model and System of Databases – The Soil and Water Assessment Tool /
Hydrologic Unit Model of the United States (SWAT/HUMUS) is used to simulate the
transport of edge-of-field losses (APEX model output) to receiving streams and routes
instream loads from one watershed to another. SWAT/HUMUS allows estimation of the
changes in in-stream concentrations of sediment, nutrients, and pesticides attributable to
conservation practice implementation.

30 The surveys, the enumerator instructions, and other documentation can be found at
https://www.nrcs.usda.gov/ceap/croplands

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The modeling strategy for estimating the effects of conservation practices consists of model
scenarios that are produced for each sample point. The effects of conservation practices are
obtained by taking the difference in model results between the various scenarios.31 For example,
to simulate “no practices” for sample points with structural and annual conservation practices
(buffers, terraces, grassed waterways, conservation tillage, nutrient management, etc.), model
simulations were conducted as if the practices were not present and compared to the results with
the practices in place to estimate the change. Multiple alternative treatment scenarios were
developed for analysis, including:
1. No Practice – simulates model results as if no conservation practices were in use but holds all other
model inputs and parameters the same as in the current conservation condition scenario (e.g., CEAP
I).
2. CEAP I and CEAP II – simulates model results that account for cropping patterns, farming activities,
and conservation practices as reported in the CEAP Cropland Surveys and other sources for each
survey period (CEAP I, 2003–06, and CEAP II, 2013–16).
3. Erosion Control (EC) – simulates model results associated with conservation practices designed to
control and trap soil losses from cropped fields primarily through additions of structural conservation
practices. Tillage practices are not altered.
4. Nutrient Management (NM) – simulates model results related to conservation practices designed to
avoid excess surface and subsurface nutrient losses through adjustments to nutrient application
method, timing, and rate. A 10-percent reduction in nutrient application rate is used in this scenario.32
Nutrient form is not adjusted as it may relate to decision factors not in the survey such as equipment
or the need to use manure from the operation.
5. Erosion Control and Nutrient Management (ENM) – simulates model results reflecting a
comprehensive conservation plan by combining the EC and NM scenarios with additional
improvements to structural conservation practices and nutrient management.
6. Erosion Control and Nutrient Management 85 (ENM85) – simulates erosion control and nutrient
management but with only 85 percent of the nutrient form being applied and with additional
improvements to nutrient timing and incorporation and runoff controls to improve nutrient-use
efficiency.

Technical information on the CEAP Cropland methodology studies, including documentation
reports on the modeling methodology, models and databases are available on the Web as part of
the CEAP Croplands Assessments.33

31 This modeling strategy is similar to NRI estimates of soil erosion and the intrinsic erosion rate used to identify highly erodible
land. The NRI uses the Universal Soil Loss Equation (USLE) to estimate sheet and rill erosion at each sample point based on sitespecific factors. Soil loss per unit area is equal to R*K*L*S*C*P. The first four factors—R, K, L, S—represent the conditions of
climate, soil, and topography existing at a site. The last two factors—C and P—represent the degree to which management
influences the erosion rate. The product of the first four factors is sometimes called the intrinsic, or potential, erosion rate. The
intrinsic erosion rate divided by T, the soil loss tolerance factor, produces estimates of the erodibility index. The intrinsic
erosion rate is thus a “no-practice” representation of sheet and rill erosion since C=1 represents smooth-tilled continuous
fallow and P=1 represents no supporting practices.
32 The 10-percent reduction was selected as a level where productivity is maintained on most soils while demonstrating the
effects of improved use efficiency that is provided through rate reductions in combination with improved timing and
application methods, particularly in precision agriculture systems.
33https://www.nrcs.usda.gov/ceap/croplands

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Conservation Effects Assessment Project

APPENDIX 2. REGIONAL TABLES
Table A-1. Cultivated Cropland Acreage by Region, CEAP I and CEAP II ........................................................................................ 107
Table A-2. Harvested Crops, Top Five by Acreage, National and by Region, CEAP I and CEAP II................................................... 108
Table A-3. Cultivated Cropland by Treatment Group by Region, CEAP I and CEAP II..................................................................... 110
Table A-4. Structural Practice Adoption by Region, CEAP I and CEAP II......................................................................................... 111
Table A-5. Structural Practice Groups by Region, CEAP I and CEAP II............................................................................................ 112
Table A-6. Tillage Groups by Region, CEAP I and CEAP II............................................................................................................... 114
Table A-7. Highly Erodible Land (HEL) Cultivated Cropland by Treatment Group and Region, CEAP I and CEAP II ....................... 115
Table A-8. Cultivated Cropland with High and Moderately High Runoff (SVI) ratings by Treatment Group and Region, CEAP I and
CEAP II ........................................................................................................................................................................................... 117
Table A-9. Conservation Crop Rotations by Group and Region, CEAP II ........................................................................................ 123
Table A-10. Nitrogen Application by Incorporation and Region, CEAP I and CEAP II..................................................................... 126
Table A-11. Phosphorus Application by Incorporation and Region, CEAP I and CEAP II ................................................................ 127
Table A-12. Nitrogen Application Timing and Incorporation by Region, CEAP I and CEAP II ......................................................... 128
Table A-13. Phosphorus Application Timing and Incorporation by Region, CEAP I and CEAP II .................................................... 131
Table A-14. Sheet and Rill Erosion Relative to Threshold by Region, CEAP I and CEAP II............................................................... 134
Table A-15. Wind Erosion Relative to Threshold by Region, CEAP I and CEAP II............................................................................ 135
Table A-16. Sediment Relative to Threshold by Region, CEAP I and CEAP II .................................................................................. 136
Table A-17. Surface Nitrogen Relative to Threshold by Region, CEAP I and CEAP II ...................................................................... 137
Table A-18. Sediment Transported Phosphorus Relative to Threshold by Region, CEAP I and CEAP II .......................................... 138
Table A-19. Subsurface Nitrogen Relative to Threshold, CEAP I and CEAP II ................................................................................. 139
Table A-20. Soluble Phosphorus Relative to Threshold by Region, CEAP I and CEAP II.................................................................. 140
Table A-21. Soil Carbon Relative to Threshold by Region, CEAP I and CEAP II............................................................................... 141
Table A-22. Sediment Management on Cultivated Cropland by Region, CEAP I and CEAP II ........................................................ 142
Table A-23. Nitrogen Management on Cultivated Cropland by Region, CEAP I and CEAP II ......................................................... 143
Table A-24. Phosphorus Management on Cultivated Cropland by Region, CEAP I and CEAP II..................................................... 144
Table A-25. Sediment Management and Soil Vulnerability Index – Runoff (SVI-R) by Region, CEAP I and CEAP II ....................... 145
Table A-26. Nitrogen Management and Soil Vulnerability Index – Leaching (SVI-L) by Region, CEAP I and CEAP II ..................... 151
Table A-27. Phosphorus Management and Soil Vulnerability Index – Runoff (SVI-R) by Region, CEAP I and CEAP II.................... 157

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Table A-1. Cultivated Cropland Acreage by Region, CEAP I and CEAP II
CEAP I

CEAP II minus CEAP
I

CEAP II

Production Region

Atlantic and Gulf Coastal
Plains
California Coastal
East Central
Lower Mississippi and
Texas Gulf Coast
North Central and
Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central
Plains
Southwest
National

Acre
Change
Relative
to CEAP I

Acres
(1,000s)

Percent

Acres
(1,000s)

Percent

Acres
(1,000s)

Percent

Percent

14,395

5

13,825

4

-570

0

-4

4,447
9,312

1
3

3,913
10,166

1
3

-534
854

0
0

-12
9

21,816

7

20,916

7

-900

0

-4

120,134

38

123,296

39

3,162

1

3

7,190
48,420
14,010
6,135

2
15
4
2

7,597
51,130
13,438
5,107

2
16
4
2

407
2,710
-571
-1,027

0
1
0
0

6
6
-4
-17

64,337

21

62,732

20

-1,605

-1

-2

2,870
313,065

1

3,183
315,303

1

313
2,238

0

11
1

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Conservation Effects Assessment Project

Table A-2. Harvested Crops, Top Five by Acreage, National and by Region, CEAP I and CEAP II
Region

Crop

CEAP I
Harvested Acres
(1,000s) (percent)

CEAP II
Harvested Acres
(1,000s) (percent)

Count

Crop

Count

11,011
10,445
4,361
2,031

92,275
89,963
43,258
16,794

29
29
14
5

1,290

Soybean
Corn
Winter Wheat
Idle/Fallow
Durum &
Spring Wheat

15,570

5

28
27
19
10
8

422
821
664
196
288

Soybean
Cotton
Corn
Winter Wheat
Peanuts

4,366
3,083
2,446
2,030
1,807

32
22
18
15
13

498
223
330
247
156

20
20
18
12
10

28
11
38
8
20

Rice
Vegetable
Winter Wheat
Corn Silage
Alfalfa/Clover

942
863
636
509
263

24
22
16
13
7

51
57
39
32
18

39
31
12
7
6

642
601
190
84
80

Soybean
Corn
Winter Wheat
Corn Silage
Close grown

4,621
3,582
1,649
389
371

45
35
16
4
4

582
480
218
43
47

40
22
13
11
5

1,183
464
430
497
170

Soybean
Corn
Rice
Cotton
Idle/Fallow

9,740
3,099
2,843
1,745
997

47
15
14
8
5

1015
446
308
180
128

National
Soybean
81,563
Corn
79,186
Winter Wheat
45,528
Idle/Fallow
20,648
Durum &
19,030
Spring Wheat
Atlantic and Gulf Coastal Plains
Cotton
4,087
Soybean
3,822
Corn
2,740
Peanuts
1,433
Winter Wheat
1,099
California Coastal
Vegetable
906
Cotton
887
Rice
814
Corn Silage
520
Idle/Fallow
436
East Central
Soybean
3,602
Corn
2,862
Winter Wheat
1,140
Cotton
654
Corn Silage
582
Lower Mississippi and Texas Gulf Coast
Soybean
8,776
Cotton
4,762
Rice
2,921
Corn
2,323
Idle/Fallow
1,121

26
25
15
7
6

7,250
6,691
2,871
1,070
765

North Central and Midwest
Corn
Soybean
Winter Wheat
Alfalfa/Clover
Corn Silage

53,893
52,460
3,965
3,211
2,533

45
44
3
3
2

6,925
7,015
874
357
300

Corn
Soybean
Winter Wheat
Alfalfa/Clover
Close grown

58,295
52,404
4,687
3,530
2,448

47
43
4
3
2

3,750
3,623
410
138
177

Corn
Corn Silage
Soybean
Alfalfa/Clover
Winter Wheat

2,450
1,405
1,354
509
498

34
20
19
7
7

555
273
393
101
172

Corn
Soybean
Corn Silage
Winter Wheat
Alfalfa/Clover

2,351
2,022
1,288
1,000
864

31
27
17
13
11

413
382
163
190
101

15,806

33

922

12,990

25

587

7,214
5,827
4,678
3,351

15
12
10
7

507
384
371
228

12,463
7,784
3,839
3,698

24
15
8
7

599
452
190
192

Northeast

Northern Plains
Durum &
Spring Wheat
Soybean
Idle/Fallow
Corn
Winter Wheat

Durum &
Spring Wheat
Soybean
Corn
Idle/Fallow
Winter Wheat

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Table A-2. Harvested Crops, Top Five by Acreage, National and by Region, CEAP I and CEAP II—Cont.
Region

Crop

CEAP I
Harvested Acres
(1,000s) (percent)

Count

Crop

CEAP II
Harvested Acres
(1,000s) (percent)

Count

Northwest
Winter Wheat
Idle/Fallow

3,917
2,758

28
20

537
382

Barley

1,610

11

251

1,452

10

827

Durum &
Spring Wheat
Alfalfa/Clover

Winter Wheat
Idle/Fallow
Durum &
Spring Wheat

4,133
2,623

31
20

314
192

1,406

10

112

203

Alfalfa/Clover

985

7

82

6

77

Barley

826

6

103

1,831
1,127
1,080
740
502

30
18
18
12
8

118
83
112
47
14

Winter Wheat
Soybean
Corn
Sorghum
Cotton

1,243
1,242
1,217
400
361

24
24
24
8
7

114
120
104
47
33

28,005
8,719
8,500
6,712
5,388

44
14
13
10
8

1,667
733
656
427
409

Winter Wheat
Corn
Cotton
Idle/Fallow
Soybean

22,609
10,582
8,479
7,134
5,418

36
17
14
11
9

969
621
296
372
431

534
448
430
324
281

19
16
15
11
10

64
66
24
29
48

Alfalfa/Clover
Winter Wheat
Cotton
Vegetable
Idle/Fallow

614
593
500
346
332

19
19
16
11
10

27
35
31
21
27

South Central
Winter Wheat
Corn
Soybean
Sorghum
Oats
Southern and Central Plains
Winter Wheat
Idle/Fallow
Corn
Cotton
Sorghum
Southwest
Cotton
Winter Wheat
Vegetable
Alfalfa/Clover
Idle/Fallow

110

Conservation Effects Assessment Project

Table A-3. Cultivated Cropland by Treatment Group by Region, CEAP I and CEAP II
CEAP I
Treatment Group and Region
Structural Practices plus Conservation Tillage
Atlantic and Gulf Coastal Plains
California Coastal
East Central
Lower Mississippi and Texas Gulf Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest
National
Structural Practices Only
Atlantic and Gulf Coastal Plains
California Coastal
East Central
Lower Mississippi and Texas Gulf Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest
National
Conservation Tillage Only
Atlantic and Gulf Coastal Plains
California Coastal
East Central
Lower Mississippi and Texas Gulf Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest
National
No Structural Practices or Conservation
Tillage
Atlantic and Gulf Coastal Plains
California Coastal
East Central
Lower Mississippi and Texas Gulf Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest
National
*** Too few acres for significance change analysis

CEAP II

Acres (1,000s)

Percent
Regional Acres

Acres (1,000s)

Percent
Regional Acres

2,157
481***
3,015
2,127
38,854
1,295
7,588
1,259
704***
7,279
100***
64,860

15
11***
32
10
32
18
16
9
11***
11
3***
21

2,934
77***
4,181
3,017
58,046
2,882
13,027
3,425
1,167
18,657
76***
107,489

21
2***
41
14
47
38
25
25
23
30
2***
34

1,747
239***
1,532
1,885
17,577
1,751
4,720
1,804
1,786
21,521
727***
55,289

12
5***
16
9
15
24
10
13
29
33
25***
18

2,210
772
640
3,384
15,720
1,125
4,559
2,396
1,383
10,819
616***
43,623

16
20
6
16
13
15
9
18
27
17
19***
14

5,189
373***
3,654
7,551
35,306
1,514
22,994
2,754
858
11,787
283***
92,265

36
8***
39
35
29
21
47
20
14
18
10***
29

5,169
507***
4,612
5,874
32,598
1,977
25,314
3,679
1,220
21,546
546***
103,042

37
13***
45
28
26
26
50
27
24
34
17***
33

5,302
3,353
1,111
10,252
28,396
2,630
13,117
8,193
2,787
23,750
1,760
100,651

37
75
12
47
24
37
27
58
45
37
61
32

3,512
2,557
733
8,641
16,931
1,614
8,230
3,938
1,337
11,711
1,944
61,148

25
65
7
41
14
21
16
29
26
19
61
19

Conservation Practices on Cultivated Cropland

111

Table A-4. Structural Practice Adoption by Region, CEAP I and CEAP II
CEAP I
Region
One Or More Structural Practices
Atlantic and Gulf Coastal Plains
California Coastal
East Central
Lower Mississippi and Texas Gulf Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest
National
More Than One Structural Practice
Atlantic and Gulf Coastal Plains
California Coastal
East Central
Lower Mississippi and Texas Gulf Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest
National
One Structural Practice
Atlantic and Gulf Coastal Plains
California Coastal
East Central
Lower Mississippi and Texas Gulf Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest
National
No Structural Practices
Atlantic and Gulf Coastal Plains
California Coastal
East Central
Lower Mississippi and Texas Gulf Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest
National
*** Too few acres for significance change analysis

CEAP II

Acres (1,000s)

Percent
Regional
Acres

Acres (1,000s)

Percent
Regional
Acres

3,904
721***
4,547
4,013
56,431
3,046
12,309
3,063
2,489
28,799
827
120,149

27
16***
49
18
47
42
25
22
41
45
29
38

5,144
849
4,821
6,401
73,766
4,007
17,586
5,821
2,550
29,475
692***
151,113

37
22
47
31
60
53
34
43
50
47
22***
48

1,827
577***
1,930
972
24,095
1,191
2,012
715
1,318
16,961
66***
51,664

13
13***
21
4
20
17
4
5
21
26
2***
17

2,362
363***
2,236
2,234
39,819
2,315
4,224
2,026
1,571
18,181
163***
75,494

17
9***
22
11
32
30
8
15
31
29
5***
24

2,076
143***
2,617
3,041
32,336
1,856
10,297
2,348
1,171
11,839
761***
68,485

14
3***
28
14
27
26
21
17
19
18
27***
22

2,782
486***
2,584
4,167
33,947
1,691
13,362
3,795
979
11,295
529***
75,619

20
12***
25
20
28
22
26
28
19
18
17***
24

10,491
3,726
4,766
17,803
63,702
4,144
36,111
10,947
3,645
35,537
2,043
192,916

73
84
51
82
53
58
75
78
59
55
71
62

8,681
3,064
5,345
14,515
49,529
3,590
33,544
7,617
2,557
33,256
2,491
164,190

63
78
53
69
40
47
66
57
50
53
78
52

112

Conservation Effects Assessment Project

Table A-5. Structural Practice Groups by Region, CEAP I and CEAP II
Region/Structural Practice Groups
Atlantic and Gulf Coastal Plains
Overland Flow Control
Concentrated Flow Control
Edge of Field Buffering and Filtering
Field Border
Wind Erosion Control
California Coastal
Overland Flow Control
Concentrated Flow Control
Edge of Field Buffering and Filtering
Field Border
Wind Erosion Control
East Central
Overland Flow Control
Concentrated Flow Control
Edge of Field Buffering and Filtering
Field Border
Wind Erosion Control
Lower Mississippi and Texas Gulf
Overland Flow Control
Concentrated Flow Control
Edge of Field Buffering and Filtering
Field Border
Wind Erosion Control
North Central and Midwest
Overland Flow Control
Concentrated Flow Control
Edge of Field Buffering and Filtering
Field Border
Wind Erosion Control
Northeast
Overland Flow Control
Concentrated Flow Control
Edge of Field Buffering and Filtering
Field Border
Wind Erosion Control
Northern Plains
Overland Flow Control
Concentrated Flow Control
Edge of Field Buffering and Filtering
Field Border
Wind Erosion Control
Northwest
Overland Flow Control
Concentrated Flow Control
Edge of Field Buffering and Filtering
Field Border
Wind Erosion Control
South Central
Overland Flow Control
Concentrated Flow Control
Edge of Field Buffering and Filtering
Field Border
Wind Erosion Control

CEAP I
Percent
Acres (1,000s)
Regional
Acres
1,925
1,777
817
1,123
309***
557***
122***
481***
50***
38***

13
12
6
8
2***
13***
3***
11***
1***
1***

Count

Acres
(1,000s)

CEAP II
Percent
Regional
Acres

Count

126
129
101
81
25

2,375
1,516
1,408
1,857
631

17
11
10
13
5

117
90
98
121
43

4
3
1
3
2

397***
185***
248***
358***
66***

10***
5***
6***
9***
2***

18
10
16
24
6

2,209
2,421
839
1,134
162***

24
26
9
12
2***

202
245
77
89
13

2,001
2,297
1,119
1,644
479

20
23
11
16
5

153
167
85
132
37

963
2,677
641
484
154***

4
12
3
2
1***

117
267
61
42
9

2,146
2,749
948
2,957
505

10
13
5
14
2

165
202
74
184
37

26,101
34,268
11,139
6,106
4,222

22
29
9
5
4

1,812
2,338
715
394
283

30,322
46,387
21,715
17,451
9,244

25
38
18
14
7

1,061
1,628
728
604
340

2,057
1,172
432
280***
281

29
16
6
4***
4

241
159
68
30
40

2,100
1,453
1,001
1,174
812

28
19
13
15
11

206
144
93
106
77

3,982
3,296
564***
860
5,110

8
7
1***
2
11

98
102
15
33
147

3,406
5,513
1,770
4,640
6,788

7
11
3
9
13

76
117
45
94
163

1,665
834
752
220***
194***

12
6
5
2***
1***

139
55
40
14
12

4,146
1,523
1,291
448***
400***

31
11
10
3***
3***

149
54
40
24
21

1,242
1,591
308***
274***
194***

20
26
5***
4***
3***

43
50
13
10
7

1,125
1,352
769
856
555***

22
26
15
17
11***

47
59
31
40
26

Conservation Practices on Cultivated Cropland

113

Table A-5. Structural Practice Groups by Region, CEAP I and CEAP II—Cont.
Region/Structural Practice Groups

CEAP I
Percent
Acres (1,000s)
Regional
Acres

Southern and Central Plains
Overland Flow Control
Concentrated Flow Control
Edge of Field Buffering and Filtering
Field Border
Wind Erosion Control
Southwest
Overland Flow Control
Concentrated Flow Control
Edge of Field Buffering and Filtering
Field Border
Wind Erosion Control
National Summary
Overland Flow Control
Concentrated Flow Control
Edge of Field Buffering and Filtering
Field Border
Wind Erosion Control
*** Too few acres for significance change analysis

Count

Acres
(1,000s)

CEAP II
Percent
Regional
Acres

Count

24,970
10,733
1,448
641***
2,534

39
17
2
1***
4

890
394
55
30
95

23,617
11,937
3,133
2,393
3,784

38
19
5
4
6

672
343
102
80
128

138***
554***
0***
62***
101***

5***
19***
0***
2***
4***

8
21
0
3
3

242***
404***
0***
243***
51***

8***
13***
0***
8***
2***

7
14
0
7
4

3,680
3,763
1,146
729
636

71,877
75,316
33,403
34,022
23,315

23
24
11
11
7

2,671
2,828
1,312
1,416
882

65,809
59,445
17,422
11,233
13,300

21
19
6
4
4

114

Conservation Effects Assessment Project

Table A-6. Tillage Groups by Region, CEAP I and CEAP II
Tillage Group and Region

Acres
(1,000s)

Conservation Tillage
Atlantic and Gulf Coastal Plains
California Coastal
East Central
Lower Mississippi and Texas Gulf Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest
National
Reduced Tillage
Atlantic and Gulf Coastal Plains
California Coastal
East Central
Lower Mississippi and Texas Gulf Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest
National
Continuous No Till
Atlantic and Gulf Coastal Plains
California Coastal
East Central
Lower Mississippi and Texas Gulf Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest
National
Conventional Tillage
Atlantic and Gulf Coastal Plains
California Coastal
East Central
Lower Mississippi and Texas Gulf Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest
National
*** Too few acres for significance change analysis

CEAP I
Percent
Regional
Acres

Count

Acres
(1,000s)

CEAP II
Percent
Regional
Acres

Count

7,346
854***
6,669
9,679
74,160
2,809
30,583
4,013
1,562
19,066
383***
157,124

51
19***
72
44
62
39
63
29
25
30
13***
50

714
7
665
949
5,166
412
995
264
75
822
24
10,093

8,103
584***
8,794
8,891
90,644
4,859
38,341
7,104
2,388
40,203
622***
210,532

59
15***
86
43
74
64
75
53
47
64
20***
67

515
14
638
651
3,185
470
961
282
137
1,119
30
8,002

3,633
560***
2,149
5,833
51,274
1,453
14,397
2,856
1,093
12,004
321***
95,572

25
13***
23
27
43
20
30
20
18
19
11***
31

315
6
207
496
3,402
194
459
174
54
535
20
5,862

3,533
511***
2,108
5,518
56,601
2,108
13,957
3,801
1,659
17,279
348***
107,423

26
13***
21
26
46
28
27
28
32
28
11***
34

209
12
146
373
1,982
188
323
151
100
488
21
3,993

3,713
294***
4,520
3,846
22,886
1,357
16,186
1,157
469***
7,062
63***
61,553

26
7***
49
18
19
19
33
8
8***
11
2***
20

399
1
458
453
1,764
218
536
90
21
287
4
4,231

4,570
73***
6,685
3,373
34,043
2,750
24,384
3,303
729
22,923
274***
103,108

33
2***
66
16
28
36
48
25
14
37
9***
33

306
2
492
278
1,203
282
638
131
37
631
9
4,009

7,049
3,593
2,643
12,137
45,973
4,381
17,838
9,997
4,572
45,271
2,487
155,941

49
81
28
56
38
61
37
71
75
70
87
50

576
104
249
871
2,899
476
523
784
157
1,793
166
8,598

5,721
3,329
1,373
12,025
32,652
2,738
12,789
6,334
2,720
22,529
2,561
104,771

41
85
14
57
26
36
25
47
53
36
80
33

249
193
102
739
1,020
196
251
265
142
684
105
3,946

Conservation Practices on Cultivated Cropland

115

Table A-7. Highly Erodible Land (HEL) Cultivated Cropland by Treatment Group and Region, CEAP I and
CEAP II
Treatment Group and Region
Structural Practices plus Conservation Tillage
Atlantic and Gulf Coastal Plains
California Coastal
East Central
Lower Mississippi and Texas Gulf Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest
National
Structural Practices Only
Atlantic and Gulf Coastal Plains
California Coastal
East Central
Lower Mississippi and Texas Gulf Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest
National
Conservation Tillage Only
Atlantic and Gulf Coastal Plains
California Coastal
East Central
Lower Mississippi and Texas Gulf Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest
National
No Structural Practices or Conservation Tillage
Atlantic and Gulf Coastal Plains
California Coastal
East Central
Lower Mississippi and Texas Gulf Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest
National

Acres
(1,000s)

CEAP I
Percent
Regional
Acres

Count

Acres
(1,000s)

CEAP II
Percent
Regional
Acres

Count

153***
0***
1,294
642
13,186
667
3,335
614
38***
1,946
97***
21,971

18***
0***
40
39
56
28
22
12
11***
8
7***
28

15
0
135
116
1,009
97
88
44
3
85
4
1,596

213***
0***
2,036
950
18,741
1,340
5,148
1,408
196***
5,763
68***
35,862

25***
0***
55
50
70
49
33
29
35***
22
4***
42

18
0
144
75
668
139
112
58
8
147
1
1,370

285***
8***
572
156***
3,368
689
1,648
824
202***
6,120
255***
14,127

34***
31***
18
9***
14
29
11
16
59***
25
18***
18

18
1
53
22
244
88
47
57
8
251
16
805

242***
58***
328***
46***
2,912
305***
680***
894***
98***
3,270
364***
9,197

29***
28***
9***
2***
11
11***
4***
18***
17***
12
20***
11

12
2
28
4
110
29
17
27
5
104
11
349

205***
0***
1,136
575
4,853
448
7,581
1,152
20***
5,103
91***
21,164

25***
0***
35
35
21
19
50
22
6***
21
6***
27

21
0
120
98
416
64
252
73
2
225
7
1,278

275***
0***
1,209
703
3,922
770
9,025
1,109
118***
10,427
367***
27,926

33***
0***
33
37
15
28
57
23
21***
39
21***
33

26
0
98
64
147
60
225
37
9
240
19
925

193***
19***
239***
291***
2,055
601
2,537
2,694
84***
11,472
969
21,155

23***
69***
7***
18***
9
25
17
51
24***
47
69
27

19
1
29
27
158
71
84
193
6
536
71
1,195

115***
153***
125***
213***
1,072
300***
911***
1,461
155***
7,309
985
12,800

14***
72***
3***
11***
4
11***
6***
30
27***
27
55
15

6
7
12
15
38
20
26
49
6
198
39
416

116

Conservation Effects Assessment Project

Table A-7. Highly Erodible Land (HEL) Cultivated Cropland by Treatment Group and Region, CEAP I and
CEAP II—Cont.
Treatment Group and Region
National Summary
Atlantic and Gulf Coastal Plains
California Coastal
East Central
Lower Mississippi and Texas Gulf Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest
National

Acres
(1,000s)
835
27***
3,241
1,665
23,462
2,406
15,101
5,284
344***
24,640
1,412
78,417

CEAP I
Percent
Regional
Acres
6
1***
35
8
20
33
31
38
6***
38
49
25

Count

Acres
(1,000s)

73
2
337
263
1,827
320
471
367
19
1,097
98
4,874

844
212***
3,699
1,911
26,648
2,714
15,764
4,873
568***
26,769
1,784
85,785

CEAP II
Percent
Regional
Acres
6
5***
36
9
22
36
31
36
11***
43
56
27

Count
62
9
282
158
963
248
380
171
28
689
70
3,060

Conservation Practices on Cultivated Cropland

117

Table A-8. Cultivated Cropland with High and Moderately High Runoff (SVI) ratings by Treatment Group
and Region, CEAP I and CEAP II
Region and Treatment Group

CEAP I
Acres
Percent
(1,000s)

CEAP II
Acres
Percent
(1,000s)

Atlantic and Gulf Coastal Plains
Structural Practices, Conservation Tillage, or Both
High
Moderately High
Structural Practices plus Conservation Tillage
High
Moderately High
Conservation Tillage Only
High
Moderately High
Structural Practices Only
High
Moderately High
No Structural Practices or Conservation Tillage
High
Moderately High
Regional Total
High
Moderately High
California Coastal
Structural Practices, Conservation Tillage, or Both
High
Moderately High
Structural Practices plus Conservation Tillage
High
Moderately High
Conservation Tillage Only
High
Moderately High
Structural Practices Only
High
Moderately High
No Structural Practices or Conservation Tillage
High
Moderately High
Regional Total
High
Moderately High

143
920

79
82

116
1,171

66
80

22
209

12
19

60
368

34
25

54
431

30
38

42
563

24
39

67
279

37
25

14
239

8
16

37
204

21
18

60
290

34
20

180
1,124

1
8

176
1,461

1
11

0
0

0
0

101
138

100
79

0
0

0
0

44
33

43
19

0
0

0
0

0
0

0
0

0
0

0
0

57
105

57
60

0
50

0
100

0
36

0
21

0
50

0
1

101
174

3
4

118

Conservation Effects Assessment Project

Table A-8. Cultivated Cropland with High and Moderately High Runoff (SVI) ratings by Treatment Group
and Region, CEAP I and CEAP II—Cont.
Region and Treatment Group

CEAP I
Acres
Percent
(1,000s)

CEAP II
Acres
Percent
(1,000s)

East Central
Structural Practices, Conservation Tillage, or Both
High
Moderately High
Structural Practices plus Conservation Tillage
High
Moderately High
Conservation Tillage Only
High
Moderately High
Structural Practices Only
High
Moderately High
No Structural Practices or Conservation Tillage
High
Moderately High
Regional Total
High
Moderately High
Lower Mississippi and Texas Gulf Coast
Structural Practices, Conservation Tillage, or Both
High
Moderately High
Structural Practices plus Conservation Tillage
High
Moderately High
Conservation Tillage Only
High
Moderately High
Structural Practices Only
High
Moderately High
No Structural Practices or Conservation Tillage
High
Moderately High
Regional Total
High
Moderately High

1,519
2,364

93
86

2,153
2,832

96
95

501
1,122

31
41

1,126
1,401

50
47

606
914

37
33

801
1,330

36
45

412
328

25
12

226
100

10
3

110
373

7
14

98
150

4
5

1,629
2,737

17
29

2,250
2,982

22
29

398
1,606

95
78

564
1,827

95
86

162
654

39
32

299
925

51
44

223
721

53
35

264
834

45
39

13
232

3
11

0
68

0
3

21
447

5
22

27
290

5
14

419
2,053

2
9

590
2,117

3
10

Conservation Practices on Cultivated Cropland

119

Table A-8. Cultivated Cropland with High and Moderately High Runoff (SVI) ratings by Treatment Group
and Region, CEAP I and CEAP II—Cont.
Region and Treatment Group

CEAP I
Acres
Percent
(1,000s)

CEAP II
Acres
Percent
(1,000s)

13,908
19,567

92
83

18,737
22,162

97
90

9,000
9,232

59
39

14,673
13,941

76
57

2,501
6,420

16
27

2,312
5,130

12
21

2,406
3,916

16
17

1,752
3,092

9
13

1,270
4,018

8
17

640
2,505

3
10

15,178
23,585

13
20

19,377
24,668

16
20

1,403
1,230

76
64

1,926
1,691

79
80

532
314

29
16

1,142
616

47
29

315
465

17
24

500
678

21
32

556
451

30
24

284
397

12
19

432
683

24
36

500
425

21
20

1,834
1,913

26
27

2,426
2,116

32
28

North Central and Midwest
Structural Practices, Conservation Tillage, or Both
High
Moderately High
Structural Practices plus Conservation Tillage
High
Moderately High
Conservation Tillage Only
High
Moderately High
Structural Practices Only
High
Moderately High
No Structural Practices or Conservation Tillage
High
Moderately High
Regional Total
High
Moderately High
Northeast
Structural Practices, Conservation Tillage, or Both
High
Moderately High
Structural Practices plus Conservation Tillage
High
Moderately High
Conservation Tillage Only
High
Moderately High
Structural Practices Only
High
Moderately High
No Structural Practices or Conservation Tillage
High
Moderately High
Regional Total
High
Moderately High

120

Conservation Effects Assessment Project

Table A-8. Cultivated Cropland with High and Moderately High Runoff (SVI) ratings by Treatment Group
and Region, CEAP I and CEAP II—Cont.
Region and Treatment Group

CEAP I
Acres
Percent
(1,000s)

CEAP II
Acres
Percent
(1,000s)

Northern Plains
Structural Practices, Conservation Tillage, or Both
High
Moderately High
Structural Practices plus Conservation Tillage
High
Moderately High
Conservation Tillage Only
High
Moderately High
Structural Practices Only
High
Moderately High
No Structural Practices or Conservation Tillage
High
Moderately High
Regional Total
High
Moderately High
Northwest
Structural Practices, Conservation Tillage, or Both
High
Moderately High
Structural Practices plus Conservation Tillage
High
Moderately High
Conservation Tillage Only
High
Moderately High
Structural Practices Only
High
Moderately High
No Structural Practices or Conservation Tillage
High
Moderately High
Regional Total
High
Moderately High

2,710
8,846

87
79

2,837
9,541

95
97

384
2,022

12
18

1,118
3,415

37
35

1,934
5,559

62
50

1,714
5,434

57
55

392
1,264

13
11

5
692

0.2
7

417
2,310

13
21

152
316

5
3

3,128
11,155

6
23

2,990
9,857

6
19

2,123
1,395

64
44

3,321
2,386

86
69

641
216

19
7

1,575
1,021

41
30

775
752

24
24

742
873

19
25

707
427

21
13

1,005
493

26
14

1,173
1,788

36
56

536
1,049

14
31

3,296
3,183

24
23

3,858
3,436

29
26

Conservation Practices on Cultivated Cropland

121

Table A-8. Cultivated Cropland with High and Moderately High Runoff (SVI) ratings by Treatment Group
and Region, CEAP I and CEAP II—Cont.
Region and Treatment Group

CEAP I
Acres
Percent
(1,000s)

CEAP II
Acres
Percent
(1,000s)

South Central
Structural Practices, Conservation Tillage, or Both
High
Moderately High
Structural Practices plus Conservation Tillage
High
Moderately High
Conservation Tillage Only
High
Moderately High
Structural Practices Only
High
Moderately High
No Structural Practices or Conservation Tillage
High
Moderately High
Regional Total
High
Moderately High
Southern and Central Plains
Structural Practices, Conservation Tillage, or Both
High
Moderately High
Structural Practices plus Conservation Tillage
High
Moderately High
Conservation Tillage Only
High
Moderately High
Structural Practices Only
High
Moderately High
No Structural Practices or Conservation Tillage
High
Moderately High
Regional Total
High
Moderately High

20
1,158

100
70

133
1,293

63
78

0
348

0
21

71
431

34
26

20
183

100
11

62
283

29
17

0
627

0
38

0
579

0
35

0
499

0
30

78
374

37
22

20
1,657

0.3
27

211
1,667

4
33

1,195
5,092

86
85

1,453
8,862

94
95

362
1,322

26
22

866
4,679

56
50

258
809

19
13

441
2,253

29
24

574
2,962

41
49

146
1,929

9
21

198
926

14
15

87
478

6
5

1,393
6,018

2
9

1,539
9,340

2
15

122

Conservation Effects Assessment Project

Table A-8. Cultivated Cropland with High and Moderately High Runoff (SVI) ratings by Treatment Group
and Region, CEAP I and CEAP II—Cont.
Region and Treatment Group

CEAP I
Acres
Percent
(1,000s)

CEAP II
Acres
Percent
(1,000s)

Southwest
Structural Practices, Conservation Tillage, or Both
High
Moderately High
Structural Practices plus Conservation Tillage
High
Moderately High
Conservation Tillage Only
High
Moderately High
Structural Practices Only
High
Moderately High
No Structural Practices or Conservation Tillage
High
Moderately High
Regional Total
High
Moderately High

35
72

51
29

0
212

0
61

0
58

0
24

0
68

0
19

20
14

30
6

0
59

0
17

15
0

22
0

0
85

0
24

33
174

49
71

14
136

100
39

68
247

2
9

14
349

0.4
11

Conservation Practices on Cultivated Cropland

123

Table A-9. Conservation Crop Rotations by Group and Region, CEAP II
Region and Crop
Rotation Group

Acres
(1,000)

Count

Acres with
Conservation
Crop Rotations*

Acres with HighBiomass
Conservation
Crop Rotations**

Acres without Conservation Crop
Rotations
Acres with Idle in
Total
one or more years
of the Rotation

Percent
Atlantic and Gulf Coastal Plains
Hay with other
451
25
crops
Close-grown
805
8
crops, no hay or
row crops
Row and close2,325
183
grown crops, no
hay
Row crops, no
10,244
548
close-grown or
hay
All cultivated
13,825
764
cropland
California Coastal
Hay with other
447
23
crops
Close-grown
1,641
65
crops, no hay or
row crops
Row and close816
38
grown crops, no
hay
Row crops, no
1,009
81
close-grown or
hay
All cultivated
3,913
207
cropland
East Central
Hay with other
833
54
crops
Close-grown
100
6
crops, no hay or
row crops
Row and close2,002
155
grown crops, no
hay
Row crops, no
7,231
525
close-grown or
hay
All cultivated
10,166
740
cropland
Lower Mississippi and Texas Gulf Coast
Hay with other
277
15
crops
Close-grown
3,195
171
crops, no hay or
row crops
Row and close4,190
290
grown crops, no
hay
Row crops, no
13,254
914
close-grown or
hay
All cultivated
20,916
1,390
cropland

89.4

87.7

10.6

14.1

98.5

98.5

1.5

0.0

94.5

82.2

5.5

0.0

34.8

19.4

65.2

4.2

50.3

36.8

49.7

4.2

92.6

83.1

7.4

0.0

75.7

75.7

24.3

100.0

64.0

64.0

36.0

27.8

27.4

26.5

72.6

7.9

62.7

61.4

37.3

36.9

99.0

89.4

1.0

100.0

100.0

100.0

0.0

0.0

96.1

82.3

3.9

66.6

68.0

22.3

32.0

3.7

76.4

40.4

23.6

6.0

72.1

66.5

27.9

67.5

58.9

56.3

41.1

99.2

81.7

27.8

18.3

22.0

36.6

8.1

63.4

6.1

49.5

20.2

50.5

19.3

124

Conservation Effects Assessment Project

Table A-9. Conservation Crop Rotations by Group and Region, CEAP II—Cont.
Region and Crop
Rotation Group

Acres
(1,000)

Count

Acres with
Conservation
Crop Rotations*

Acres with HighBiomass
Conservation
Crop Rotations**

Acres without Conservation Crop
Rotations
Acres with Idle in
Total
one or more years
of the Rotation

Percent
North Central and Midwest
Hay with other
6,539
crops
Close-grown
785
crops, no hay or
row crops
Row and close10,601
grown crops, no
hay
Row crops, no
105,371
close-grown or
hay
All cultivated
123,296
cropland
Northeast
Hay with other
1,669
crops
Close-grown
118
crops, no hay or
row crops
Row and close1,751
grown crops, no
hay
Row crops, no
4,059
close-grown or
hay
All cultivated
7,597
cropland
Northern Plains
Hay with other
2,635
crops
Close-grown
13,636
crops, no hay or
row crops
Row and close21,156
grown crops, no
hay
Row crops, no
13,703
close-grown or
hay
All cultivated
51,130
cropland
Northwest
Hay with other
1,437
crops
Close-grown
7,694
crops, no hay or
row crops
Row and close3,376
grown crops, no
hay
Row crops, no
931
close-grown or
hay
All cultivated
13,438
cropland

154

96.6

94.8

3.4

0.0

7

22.4

22.4

77.6

100.0

382

79.9

31.0

20.1

8.5

3,662

88.1

14.2

11.9

11.3

4,205

87.4

20.0

12.6

14.2

124

96.3

95.3

3.7

100.0

8

79.3

79.3

20.7

100.0

161

84.3

63.7

15.7

58.4

373

73.4

31.6

26.6

6.2

666

81.0

53.7

19.0

21.7

84

86.3

74.2

13.7

91.8

296

46.7

30.9

53.3

94.8

483

63.2

11.1

36.8

12.3

349

64.1

9.3

35.9

7.6

1,212

60.2

19.2

39.8

42.1

83

99.1

96.1

0.9

100.0

280

28.0

26.1

72.0

98.1

136

51.0

13.3

49.0

11.2

48

12.7

6.2

87.3

3.0

547

40.3

29.0

59.7

70.6

Conservation Practices on Cultivated Cropland

125

Table A-9. Conservation Crop Rotations by Group and Region, CEAP II—Cont.
Region and Crop
Rotation Group

Acres
(1,000)

Count

Acres with
Conservation
Crop Rotations*

Acres with HighBiomass
Conservation
Crop Rotations**

Acres without Conservation Crop
Rotations
Acres with Idle in
Total
one or more years
of the Rotation

Percent
South Central
Hay with other
453
crops
Close-grown
530
crops, no hay or
row crops
Row and close2,011
grown crops, no
hay
Row crops, no
2,113
close-grown or
hay
All cultivated
5,107
cropland
Southern and Central Plains
Hay with other
4,852
crops
Close-grown
18,157
crops, no hay or
row crops
Row and close16,919
grown crops, no
hay
Row crops, no
22,804
close-grown or
hay
All cultivated
62,732
cropland
Southwest
Hay with other
1,193
crops
Close-grown
630
crops, no hay or
row crops
Row and close571
grown crops, no
hay
Row crops, no
790
close-grown or
hay
All cultivated
3,183
cropland

32

100.0

95.7

0.0

0.0

31

51.0

46.4

49.0

100.0

111

92.8

66.3

7.2

34.2

105

55.5

26.1

44.5

22.5

279

73.7

50.2

26.3

38.7

141

71.3

65.5

28.7

80.5

464

53.9

51.9

46.1

99.0

427

55.6

34.1

44.4

88.4

771

58.4

26.2

41.6

10.2

1,803

57.4

38.8

42.6

63.6

42

90.1

90.1

9.9

7.4

23

30.1

30.1

69.9

100.0

25

48.2

16.0

51.8

21.4

45

11.4

11.4

88.6

26.4

135

51.2

45.4

48.8

44.9

* Acres with a crop rotation biomass index score greater than or equal to 1.5
** Acres with a crop rotation biomass index score greater than or equal to 2.0

126

Conservation Effects Assessment Project

Table A-10. Nitrogen Application by Incorporation and Region, CEAP I and CEAP II
Region

Applications
Incorporated

CEAP I
Average
Applied Acres
Annual
(1,000s)
Load (Tons)

Atlantic and Gulf Coastal Plains
All
5,244
Some
5,191
None
3,187
California Coastal
All
2,130
Some
895
None
631
East Central
All
2,376
Some
3,651
None
2,872
Lower Mississippi and Texas Gulf Coast
All
6,700
Some
6,345
None
4,706
North Central and Midwest
All
55,860
Some
45,794
None
13,694
Northeast
All
2,414
Some
3,454
None
1,065
Northern Plains
All
33,146
Some
10,501
None
2,822
Northwest
All
8,031
Some
3,761
None
1,901
South Central
All
2,575
Some
1,839
None
1,535
Southern and Central Plains
All
32,737
Some
18,498
None
8,083
Southwest
All
1,052
Some
1,418
None
277

Count

CEAP II
Average
Applied Acres
Annual
(1,000s)
Load (Tons)

Count

223,611
258,082
119,621

430
500
288

2,716
5,775
4,403

93,937
282,570
160,678

143
317
246

152,210
108,644
69,242

64
34
9

904
2,134
494

42,705
191,172
23,508

45
118
37

115,143
182,313
131,247

234
366
277

1,192
3,528
4,947

48,978
184,091
234,656

79
258
366

316,551
337,315
210,066

487
538
469

4,324
6,540
5,592

196,616
391,308
260,718

229
441
404

2,183,989
2,074,316
449,583

3694
3061
969

40,029
58,035
20,292

1,727,760
2,810,193
740,370

1361
1966
734

97,128
199,569
50,468

262
416
178

1,774
3,613
1,994

66,953
200,187
98,583

142
307
192

801,565
317,500
82,520

1004
349
101

26,274
17,514
4,768

811,072
687,296
175,509

592
423
138

252,198
227,441
97,545

566
294
166

6,553
3,943
2,499

191,570
240,744
118,957

244
164
116

113,403
88,189
61,199

81
80
62

1,441
1,765
1,431

53,710
93,604
70,784

66
107
77

978,233
710,712
230,505

1332
764
319

21,331
24,923
10,419

599,833
989,328
299,894

615
712
306

41,340
140,917
10,944

85
78
23

884
1,246
788

30,694
106,003
39,501

35
54
32

Conservation Practices on Cultivated Cropland

127

Table A-11. Phosphorus Application by Incorporation and Region, CEAP I and CEAP II
Region

Applications
Incorporated

CEAP I
Average
Applied Acres
Annual Load
(1,000s)
(Tons)

Atlantic and Gulf Coastal Plains
All
4,803
Some
5,056
None
3,083
California Coastal
All
1,370
Some
895
None
505
East Central
All
2,373
Some
3,569
None
2,750
Lower Mississippi and Texas Gulf Coast
All
6,113
Some
6,144
None
4,128
North Central and Midwest
All
55,107
Some
45,455
None
13,320
Northeast
All
2,357
Some
3,402
None
982
Northern Plains
All
30,423
Some
10,386
None
2,416
Northwest
All
5,180
Some
3,452
None
1,290
South Central
All
1,935
Some
1,839
None
1,104
Southern and Central Plains
All
23,010
Some
17,817
None
5,929
Southwest
All
705
Some
1,378
None
197

Count

CEAP II
Average
Applied Acres
Annual Load
(1,000s)
(tons)

Count

57,643
62,825
31,719

398
485
279

2,657
5,463
4,158

29,365
61,980
40,467

130
296
236

25,536
19,997
6,835

48
34
6

575
2,052
376

6,709
38,484
5,835

30
112
31

33,011
49,516
37,397

234
361
270

1,193
3,350
5,003

14,724
46,103
73,192

77
248
372

54,586
64,164
39,482

453
519
435

5,991
6,276
5,467

60,286
76,950
53,851

346
423
398

523,582
527,005
135,044

3650
3036
934

40,118
57,329
19,502

439,128
700,839
243,774

1371
1941
717

28,217
57,679
15,378

259
408
165

1,662
3,541
1,877

16,679
52,187
25,973

132
301
181

168,544
66,158
16,479

924
346
85

25,339
17,314
4,308

189,356
141,363
40,965

580
417
128

46,167
43,997
16,859

372
270
116

5,718
3,533
1,897

39,055
54,901
23,879

202
149
97

16,396
17,909
8,958

64
80
52

1,386
1,732
1,148

12,452
19,602
11,787

70
105
63

151,936
123,911
39,874

950
731
237

15,894
23,844
7,911

111,530
194,861
58,405

457
679
231

10,492
36,443
3,835

54
74
16

462
1,160
624

4,145
30,445
10,925

18
52
24

128

Conservation Effects Assessment Project

Table A-12. Nitrogen Application Timing and Incorporation by Region, CEAP I and CEAP II
Region

Timing

Incorporation

Atlantic and Gulf Coastal Plains
Pre-plant 7-21 days
Incorporated
Not Incorporated
Pre-plant >21 days
Incorporated
Not Incorporated
At-plant
Incorporated
Not Incorporated
Post-plant
Incorporated
Not Incorporated
California Coastal
Pre-plant 7-21 days
Incorporated
Not Incorporated
Pre-plant >21 days
Incorporated
Not Incorporated
At-plant
Incorporated
Not Incorporated
Post-plant
Incorporated
Not Incorporated
East Central
Pre-plant 7-21 days
Incorporated
Not Incorporated
Pre-plant >21 days
Incorporated
Not Incorporated
At-plant
Incorporated
Not Incorporated
Post-plant
Incorporated
Not Incorporated
Lower Mississippi and Texas Gulf Coast
Pre-plant 7-21 days
Incorporated
Not Incorporated
Pre-plant >21 days
Incorporated
Not Incorporated
At-plant
Incorporated
Not Incorporated
Post-plant
Incorporated
Not Incorporated

CEAP I
Average
Application
Annual
Acres (1,000s)
Load
(Tons)

Count

CEAP II
Average
Application
Annual
Acres (1,000s)
Load
(Tons)

Count

2,009
1,330

53,748
19,594

148
147

1,338
2,128

25,076
23,280

72
137

1,551
1,864

39,680
41,921

135
175

1,604
2,786

35,720
52,473

80
184

5,970
3,260

112,671
56,835

559
351

4,861
4,282

77,667
89,899

267
275

5,388
3,310

159,607
89,831

453
252

3,707
4,454

103,919
109,239

216
205

450
107

22,533
1,881

19
4

770
377

30,165
6,190

46
26

531
259

18,168
4,872

14
8

595
829

35,420
14,451

32
42

2,082
488

99,429
23,817

60
12

2,055
883

69,988
17,879

107
55

915
972

38,846
48,653

30
23

345
1,665

12,554
36,510

24
106

829
1,387

21,942
30,321

79
139

499
2,198

15,596
55,113

35
174

622
1,521

18,252
37,875

60
150

418
3,087

11,759
76,811

31
247

4,147
3,421

98,213
90,711

419
329

3,088
4,260

63,761
111,588

226
306

2,243
1,632

62,354
41,053

229
173

1,743
2,725

47,439
67,115

120
215

895
1,153

25,034
28,968

93
134

1,453
1,279

43,356
31,085

82
83

1,551
1,174

44,304
35,077

100
126

2,055
2,069

62,387
51,938

93
144

5,292
3,157

156,629
76,663

448
347

3,313
4,238

98,646
103,045

219
318

5,335
6,397

226,024
239,179

408
497

3,403
8,074

116,399
332,255

210
549

Conservation Practices on Cultivated Cropland

129

Table A-12. Nitrogen Application Timing and Incorporation by Region, CEAP I and CEAP II—Cont.
Region

Timing

Incorporation

North Central and Midwest
Pre-plant 7-21 days
Incorporated
Not Incorporated
Pre-plant >21 days
Incorporated
Not Incorporated
At-plant
Incorporated
Not Incorporated
Post-plant
Incorporated
Not Incorporated
Northeast
Pre-plant 7-21 days
Incorporated
Not Incorporated
Pre-plant >21 days
Incorporated
Not Incorporated
At-plant
Incorporated
Not Incorporated
Post-plant
Incorporated
Not Incorporated
Northern Plains
Pre-plant 7-21 days
Incorporated
Not Incorporated
Pre-plant >21 days
Incorporated
Not Incorporated
At-plant
Incorporated
Not Incorporated
Post-plant
Incorporated
Not Incorporated
Northwest
Pre-plant 7-21 days
Incorporated
Not Incorporated
Pre-plant >21 days
Incorporated
Not Incorporated
At-plant
Incorporated
Not Incorporated
Post-plant
Incorporated
Not Incorporated

CEAP I
Average
Application
Annual
Acres (1,000s)
Load
(Tons)

Count

CEAP II
Average
Application Annual
Acres (1,000s) Load
(Tons)

Count

13,001
5,927

373,286
116,001

860
424

17,471
13,854

531,202
229,789

608
460

34,525
23,696

1,081,118
445,569

2086
1497

31,782
33,411

956,353
512,203

1040
1152

63,656
19,078

1,428,509
370,455

4445
1425

53,376
22,846

1,096,451
421,154

1836
844

18,445
8,959

549,272
198,436

1365
618

34,288
23,731

1,019,138
396,842

1204
813

676
715

15,950
13,938

85
97

536
1,117

12,607
20,123

48
119

849
1,670

24,404
51,822

106
214

702
2,219

21,065
56,373

50
209

5,085
1,832

110,990
41,073

562
275

4,547
2,979

79,961
64,978

375
271

1,068
1,539

24,104
44,990

131
200

1,422
1,972

28,657
56,664

116
179

3,279
1,381

48,749
22,674

96
50

3,586
4,276

75,321
84,760

82
105

7,524
3,634

166,828
71,176

215
123

6,173
5,768

168,488
121,557

123
149

39,155
5,711

674,359
100,792

1212
206

37,704
10,448

743,358
228,100

886
274

889
1,374

20,406
27,454

38
46

2,993
3,761

43,103
60,951

76
94

2,272
313

55,078
7,422

177
34

1,580
1,021

44,412
24,266

73
46

3,538
1,350

81,157
41,908

253
107

3,462
3,003

75,972
54,227

107
139

7,177
1,229

179,737
29,478

540
98

7,018
1,398

153,595
34,210

282
54

567
827

14,195
40,050

59
84

514
902

15,598
48,380

26
55

130

Conservation Effects Assessment Project

Table A-12. Nitrogen Application Timing and Incorporation by Region, CEAP I and CEAP II—Cont.
Region

Timing

Incorporation

South Central
Pre-plant 7-21 days
Incorporated
Not Incorporated
Pre-plant >21 days
Incorporated
Not Incorporated
At-plant
Incorporated
Not Incorporated
Post-plant
Incorporated
Not Incorporated
Southern and Central Plains
Pre-plant 7-21 days
Incorporated
Not Incorporated
Pre-plant >21 days
Incorporated
Not Incorporated
At-plant
Incorporated
Not Incorporated
Post-plant
Incorporated
Not Incorporated
Southwest
Pre-plant 7-21 days
Incorporated
Not Incorporated
Pre-plant >21 days
Incorporated
Not Incorporated
At-plant
Incorporated
Not Incorporated
Post-plant
Incorporated
Not Incorporated

CEAP I
Average
Application
Annual
Acres
Load
(1,000s)
(Tons)

Count

CEAP II
Average
Application
Annual
Acres
Load
(1,000s)
(Tons)

Count

725
149

11,253
2,014

23
12

591
407

8,817
9,044

32
22

1,192
628

28,993
17,607

35
23

1,358
1,597

28,950
37,138

63
86

2,899
1,368

72,426
31,729

109
56

1,373
933

31,699
17,274

76
57

1,143
845

28,580
25,200

38
45

831
1,279

23,563
48,376

38
69

5,410
2,581

113,824
44,788

236
114

5,841
5,340

111,789
79,432

183
148

17,331
8,930

462,332
175,751

707
363

16,325
20,335

398,124
336,036

453
590

33,379
8,167

589,547
146,985

1359
327

26,598
9,471

340,601
153,151

795
298

4,627
3,742

144,481
103,375

217
185

7,221
8,650

164,236
211,432

210
259

466
120

8,031
4,490

24
8

285
85

5,305
1,743

15
8

572
394

21,774
13,578

47
26

593
983

20,936
16,364

30
35

1,289
474

36,070
6,346

78
18

1,318
466

30,655
9,308

50
18

633
518

27,243
21,618

51
35

506
942

20,236
46,788

17
39

Conservation Practices on Cultivated Cropland

131

Table A-13. Phosphorus Application Timing and Incorporation by Region, CEAP I and CEAP II
Region

Timing

Incorporation

Atlantic and Gulf Coastal Plains
Pre-plant 7-21 days
Incorporated
Not Incorporated
Pre-plant >21 days
Incorporated
Not Incorporated
At-plant
Incorporated
Not Incorporated
Post-plant
Incorporated
Not Incorporated
California Coastal
Pre-plant 7-21 days
Incorporated
Not Incorporated
Pre-plant >21 days
Incorporated
Not Incorporated
At-plant
Incorporated
Not Incorporated
Post-plant
Incorporated
Not Incorporated
East Central
Pre-plant 7-21 days
Incorporated
Not Incorporated
Pre-plant >21 days
Incorporated
Not Incorporated
At-plant
Incorporated
Not Incorporated
Post-plant
Incorporated
Not Incorporated
Lower Mississippi and Texas Gulf Coast
Pre-plant 7-21 days
Incorporated
Not Incorporated
Pre-plant >21 days
Incorporated
Not Incorporated
At-plant
Incorporated
Not Incorporated
Post-plant
Incorporated
Not Incorporated

CEAP I
Average
Application
Annual
Acres (1,000s)
Load
(Tons)

Count

CEAP II
Average
Application
Annual
Acres (1,000s)
Load
(Tons)

Count

1,996
1,311

17,504
8,700

149
150

1,309
2,357

9,661
14,396

72
134

1,713
2,017

18,165
17,362

163
175

1,874
2,251

13,911
17,980

78
134

5,057
2,937

38,618
23,092

476
303

3,469
3,598

21,904
25,278

208
226

1,389
1,143

16,842
8,482

84
93

1,232
2,222

13,673
12,733

37
83

187
107

5,890
950

8
4

413
243

3,391
1,325

27
17

474
191

4,543
1,473

11
6

552
641

11,572
4,859

25
28

1,425
707

17,279
5,784

43
12

1,172
589

10,984
5,423

71
38

160
460

2,504
4,980

8
12

187
712

1,802
5,477

13
41

754
1,364

6,882
12,172

71
140

334
2,331

3,120
22,991

25
180

733
1,556

7,757
15,689

69
164

376
2,878

3,441
30,139

28
224

3,574
3,169

36,282
30,397

355
317

2,400
3,950

19,282
39,247

174
287

426
514

5,165
3,780

38
58

278
1,269

1,644
8,272

18
102

1,063
1,174

7,289
9,121

87
143

2,323
1,520

21,581
10,665

130
95

2,278
1,489

17,184
11,027

142
148

3,202
2,029

27,239
14,220

175
131

6,071
3,019

49,507
24,657

487
360

6,077
4,210

54,992
35,131

395
327

1,504
2,541

15,377
22,607

99
207

1,118
2,432

7,835
18,645

65
163

132

Conservation Effects Assessment Project

Table A-13. Phosphorus Application Timing and Incorporation by Region, CEAP I and CEAP II—Cont.
Region

Timing

Incorporation

North Central and Midwest
Pre-plant 7-21 days
Incorporated
Not Incorporated
Pre-plant >21 days
Incorporated
Not Incorporated
At-plant
Incorporated
Not Incorporated
Post-plant
Incorporated
Not Incorporated
Northeast
Pre-plant 7-21 days
Incorporated
Not Incorporated
Pre-plant >21 days
Incorporated
Not Incorporated
At-plant
Incorporated
Not Incorporated
Post-plant
Incorporated
Not Incorporated
Northern Plains
Pre-plant 7-21 days
Incorporated
Not Incorporated
Pre-plant >21 days
Incorporated
Not Incorporated
At-plant
Incorporated
Not Incorporated
Post-plant
Incorporated
Not Incorporated
Northwest
Pre-plant 7-21 days
Incorporated
Not Incorporated
Pre-plant >21 days
Incorporated
Not Incorporated
At-plant
Incorporated
Not Incorporated
Post-plant
Incorporated
Not Incorporated

CEAP I
Average
Application
Annual
Acres (1,000s)
Load
(Tons)

Count

CEAP II
Average
Application
Annual
Acres (1,000s)
Load
(Tons)

Count

8,436
5,241

64,514
41,200

525
381

10,564
12,109

86,430
97,621

358
421

24,702
28,758

226,077
287,610

1475
1827

21,034
34,713

183,942
317,150

668
1173

55,364
14,863

391,995
109,934

3968
1119

45,684
14,728

342,303
105,457

1626
560

2,752
2,489

26,268
19,463

170
181

9,570
17,352

85,852
132,296

299
602

725
611

5,806
4,058

94
82

499
962

3,152
7,689

44
102

905
1,652

10,320
19,282

113
211

696
1,738

6,878
17,428

52
160

4,524
1,275

37,597
8,344

499
189

3,762
2,127

23,978
15,914

301
189

323
704

2,198
9,016

48
83

248
953

1,312
9,770

19
82

1,720
554

8,797
1,802

58
20

2,955
2,121

18,282
10,773

71
52

4,272
2,133

23,892
12,313

133
71

4,684
2,980

29,479
25,881

99
81

36,486
2,546

185,236
10,935

1117
102

36,739
6,506

220,223
35,440

859
174

174
252

1,395
1,439

9
9

1,908
1,029

8,889
4,925

45
32

1,634
266

12,257
1,583

133
27

1,224
671

7,879
4,631

60
30

1,465
900

15,801
10,628

129
74

1,674
1,177

17,121
6,686

67
66

5,556
890

37,138
6,678

418
65

6,596
1,095

38,827
5,512

243
42

629
417

3,604
3,639

45
50

286
626

3,028
16,044

13
37

Conservation Practices on Cultivated Cropland

133

Table A-13. Phosphorus Application Timing and Incorporation by Region, CEAP I and CEAP II—Cont.
Region

Timing

Incorporation

South Central
Pre-plant 7-21 days
Incorporated
Not Incorporated
Pre-plant >21 days
Incorporated
Not Incorporated
At-plant
Incorporated
Not Incorporated
Post-plant
Incorporated
Not Incorporated
Southern and Central Plains
Pre-plant 7-21 days
Incorporated
Not Incorporated
Pre-plant >21 days
Incorporated
Not Incorporated
At-plant
Incorporated
Not Incorporated
Post-plant
Incorporated
Not Incorporated
Southwest
Pre-plant 7-21 days
Incorporated
Not Incorporated
Pre-plant >21 days
Incorporated
Not Incorporated
At-plant
Incorporated
Not Incorporated
Post-plant
Incorporated
Not Incorporated

CEAP I
Average
Application
Annual
Acres
Load
(1,000s)
(Tons)

Count

CEAP II
Average
Application
Annual
Acres
Load
(1,000s)
(Tons)

Count

740
165

4,810
876

28
12

664
404

3,855
2,826

37
14

976
344

5,444
1,430

31
17

1,174
845

7,143
5,185

58
44

2,062
971

16,331
5,240

87
43

1,566
659

12,344
4,988

89
38

317
437

2,133
2,165

14
23

399
463

2,702
2,962

17
24

3,048
1,599

14,684
9,669

140
71

3,880
3,151

21,798
14,294

117
85

10,201
4,426

68,140
27,250

417
188

7,802
9,671

49,419
62,787

218
282

26,294
5,034

140,971
25,147

1065
189

24,836
6,457

138,651
31,514

721
186

1,449
893

10,553
6,324

63
42

2,041
3,407

11,642
16,147

69
91

264
91

2,981
2,076

20
6

242
57

2,610
1,244

10
5

500
285

9,417
6,479

38
18

443
480

11,001
3,431

22
21

850
257

11,163
4,430

55
9

883
397

6,688
6,952

34
13

166
76

956
3,191

18
6

162
208

1,350
1,233

4
12

134

Conservation Effects Assessment Project

Table A-14. Sheet and Rill Erosion Relative to Threshold by Region, CEAP I and CEAP II
Region

Atlantic and Gulf
Coastal Plains
California Coastal
East Central
Lower Mississippi
and Texas Gulf Coast
North Central and
Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central
Plains
Southwest
National
Atlantic and Gulf
Coastal Plains
California Coastal
East Central
Lower Mississippi
and Texas Gulf Coast
North Central and
Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central
Plains
Southwest
National

Cultivated Cropland
Exceeding Threshold
Acres
Percent
(1,000s)

Cultivated Cropland
Meeting Threshold
Acres
Percent
(1,000s)
CEAP I

Loss on Acres
Exceeding Threshold
Tons
Percent
(1,000s)

Loss on Acres
Meeting Threshold
Tons
Percent
(1,000s)

2,245.6

16

12,148.9

84

21,968

60

14,705

40

57.6
3,305.1

1
35

4,389.0
6,007.3

99
65

338
31,649

26
79

968
8,363

74
21

3,567.3

16

18,248.4

84

35,246

55

28,634

45

18,133.4

15

102,000.1

85

176,671

60

118,543

40

2,772.4
759.6
220.1
1,516.9

39
2
2
25

4,417.9
47,660.7
13,789.6
4,617.7

61
98
98
75

23,803
4,553
1,395
15,267

79
14
29
62

6,259
28,098
3,407
9,455

21
86
71
38

2,940.9

5

61,395.9

95

20,899

30

48,280

70

35,519

0
11

2,870.4
100
277,546
89
CEAP II

331,789

0
55

120
266,834

100
45

2,006.5

15

11,818.2

85

22,070

62

13,350

38

38.7
3,257.8

1
32

3,874.2
6,908.4

99
68

345
31,965

28
77

873
9,745

72
23

3,412.4

16

17,503.5

84

32,729

55

26,570

45

16,324.3

13

106,971.6

87

150,280

57

113,539

43

2,395.0
753.4
84.8
1,455.7

32
1
1
29

5,202.0
50,376.8
13,353.5
3,651.6

68
99
99
71

18,174
4,833
919
15,011

75
19
28
71

6,077
20,825
2,380
6,139

25
81
72
29

1,352.9

2

61,378.8

98

9,389

20

36,597

80

89.5
31,171

3
10

3,093.5
284,132

97
90

296
286,012

65
55

156
236,252

35
45

Conservation Practices on Cultivated Cropland

135

Table A-15. Wind Erosion Relative to Threshold by Region, CEAP I and CEAP II
Region

Atlantic and Gulf Coastal
Plains
California Coastal
East Central
Lower Mississippi and Texas
Gulf Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest
National
Atlantic and Gulf Coastal
Plains
California Coastal
East Central
Lower Mississippi and Texas
Gulf Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest
National

Cultivated Cropland Cultivated Cropland
Loss on Acres
Loss on Acres
Exceeding Threshold Meeting Threshold Exceeding Threshold Meeting Threshold
Acres
Acres
Tons
Tons
Percent
Percent
Percent
Percent
(1,000s)
(1,000s)
(1,000s)
(1,000s)
CEAP I
-

0

14,395

100

-

0

1,284

100

-

0
0

4,447
9,312

100
100

-

0
0

133
204

100
100

373

2

21,443

98

2,836

29

6,849

71

2,653
11,267
3,660
64
19,676
941
38,634

2
0
23
26
1
31
33
12

117,481
7,190
37,153
10,350
6,070
44,661
1,930
274,431
CEAP II

98
100
77
74
99
69
67
88

20,770
83,096
25,780
342
199,396
12,466
344,686

24
0
57
64
7
67
80
57

67,120
418
62,228
14,295
4,458
98,885
3,044
258,919

76
100
43
36
93
33
20
43

-

0

13,825

100

-

0

659

100

-

0
0

3,913
10,166

100
100

-

0
0

102
138

100
100

537

3

20,379

97

5,054

52

4,737

48

1,875
12,253
1,870
106
13,549
802
30,994

2
0
24
14
2
22
25
10

121,421
7,597
38,877
11,568
5,001
49,183
2,381
284,309

98
100
76
86
98
78
75
90

13,809
94,851
16,295
610
174,193
7,025
311,836

21
0
66
58
20
70
73
61

52,996
225
48,979
11,747
2,379
73,327
2,615
197,904

79
100
34
42
80
30
27
39

136

Conservation Effects Assessment Project

Table A-16. Sediment Relative to Threshold by Region, CEAP I and CEAP II
Region

Atlantic and Gulf
Coastal Plains
California Coastal
East Central
Lower Mississippi
and Texas Gulf
North Central
Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and
Central Plains
Southwest
National
Atlantic and Gulf
Coastal Plains
California Coastal
East Central
Lower Mississippi
and Texas Gulf
North Central
Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and
Central Plains
Southwest
National

Cultivated Cropland
Exceeding Threshold
Acres
Percent
(1,000s)

Cultivated Cropland
Meeting Threshold
Acres
Percent
(1,000s)
CEAP I

Loss on Acres
Exceeding Threshold
Tons
Percent
(1,000s)

Loss on Acres
Meeting Threshold
Tons
Percent
(1,000s)

1,949

14

12,445

86

11,329

71

4,713

29

108
2,694

2
29

4,339
6,619

98
71

928
20,777

53
85

826
3,561

47
15

6,067

28

15,749

72

39,696

80

9,690

20

17,262

14

102,872

86

112,803

74

39,791

26

2,437
1,783
922
2,172

34
4
7
35

4,754
46,638
13,087
3,963

66
96
93
65

16,757
6,606
5,855
14,319

86
38
64
83

2,816
10,716
3,246
2,868

14
62
36
17

2,695

4

61,641

96

12,508

42

17,463

58

24
38,113

1
12

2,846
274,952
CEAP II

99
88

110
241,689

30
72

258
95,946

70
28

1,663

12

12,162

88

11,341

72

4,310

28

200
2,868

5
28

3,713
7,298

95
72

1,056
21,079

54
85

906
3,627

46
15

5,104

24

15,812

76

28,860

74

9,999

26

13,613

11

109,682

89

81,469

69

36,841

31

1,766
758
472
1,666

23
1
4
33

5,831
50,373
12,967
3,442

77
99
96
67

12,564
3,229
3,640
11,101

82
29
62
83

2,771
7,885
2,240
2,218

18
71
38
17

1,104

2

61,628

98

5,266

30

12,177

70

122
29,335

4
9

3,061
285,968

96
91

632
180,237

72
68

244
83,218

28
32

Conservation Practices on Cultivated Cropland

137

Table A-17. Surface Nitrogen Relative to Threshold by Region, CEAP I and CEAP II
Region

Atlantic and Gulf Coastal
Plains
California Coastal
East Central
Lower Mississippi and Texas
Gulf Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest
National
Atlantic and Gulf Coastal
Plains
California Coastal
East Central
Lower Mississippi and Texas
Gulf Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest
National

Cultivated Cropland Cultivated Cropland
Loss on Acres
Loss on Acres
Exceeding Threshold Meeting Threshold Exceeding Threshold Meeting Threshold
Acres
Acres
Tons
Tons
Percent
Percent
Percent
Percent
(1,000s)
(1,000s)
(1,000s)
(1,000s)
CEAP I
294

2

14,101

98

4

22

15

78

58
1,478

1
16

4,389
7,834

99
84

1
22

35
60

1
15

65
40

2,262

10

19,554

90

32

45

40

55

11,517
1,118
8,578
871
1,387
7,310
209
35,084

10
16
18
6
23
11
7
11

108,617
6,072
39,842
13,139
4,748
57,027
2,661
277,981
CEAP II

90
84
82
94
77
89
93
89

164
16
97
11
18
85
2
452

45
56
47
25
59
32
33
42

202
12
108
32
12
179
5
621

55
44
53
75
41
68
67
58

481

3

13,344

97

7

31

16

69

49
1,770

1
17

3,864
8,396

99
83

1
30

29
63

2
18

71
37

2,277

11

18,639

89

29

43

40

57

9,039
1,047
11,442
606
1,326
5,764
143
33,946

7
14
22
5
26
9
4
11

114,257
6,550
39,688
12,832
3,781
56,968
3,040
281,357

93
86
78
95
74
91
96
89

157
17
153
10
21
69
2
497

45
60
63
32
69
34
25
48

196
12
92
21
9
132
5
541

55
40
37
68
31
66
75
52

138

Conservation Effects Assessment Project

TableA-18. Sediment-Transported Phosphorus Relative to Threshold by Region, CEAP I and CEAP II
Region

Atlantic and Gulf Coastal
Plains
California Coastal
East Central
Lower Mississippi and Texas
Gulf Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest
National
Atlantic and Gulf Coastal
Plains
California Coastal
East Central
Lower Mississippi and Texas
Gulf Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest
National

Cultivated Cropland Cultivated Cropland
Loss on Acres
Loss on Acres
Exceeding Threshold Meeting Threshold Exceeding Threshold Meeting Threshold
Acres
Acres
Tons
Tons
Percent
Percent
Percent
Percent
(1,000s)
(1,000s)
(1,000s)
(1,000s)
CEAP I
1,543

11

12,852

89

5.0

57

3.7

43

79
2,396

2
26

4,368
6,917

98
74

0.3
11.1

37
81

0.5
2.6

63
19

3,102

14

18,714

86

11.4

62

6.9

38

14,678
2,614
2,705
1,007
1,660
5,170
257
35,211

12
36
6
7
27
8
9
11

105,456
4,576
45,715
13,002
4,475
59,166
2,614
277,854
CEAP II

88
64
94
93
73
92
91
89

56.5
12.9
6.7
3.6
5.0
16.6
1.1
130

62
86
29
51
71
41
64
57

34.6
2.0
16.4
3.5
2.1
23.7
0.6
97

38
14
71
49
29
59
36
43

1,606

12

12,218

88

6.0

65

3.3

35

61
2,743

2
27

3,852
7,424

98
73

0.2
12.4

27
82

0.5
2.7

73
18

2,845

14

18,071

86

9.3

58

6.8

42

13,640
2,334
4,730
836
1,221
3,476
138
33,630

11
31
9
6
24
6
4
11

109,655
5,264
46,400
12,602
3,886
59,256
3,045
281,673

89
69
91
94
76
94
96
89

59.6
10.9
12.0
3.2
4.4
11.1
0.4
129

65
85
45
61
72
39
41
61

32.1
1.9
14.6
2.1
1.7
17.1
0.5
83

35
15
55
39
28
61
59
39

Conservation Practices on Cultivated Cropland

139

Table A-19. Subsurface Nitrogen Relative to Threshold, CEAP I and CEAP II
Region

Atlantic and Gulf Coastal
Plains
California Coastal
East Central
Lower Mississippi and Texas
Gulf Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest
National
Atlantic and Gulf Coastal
Plains
California Coastal
East Central
Lower Mississippi and Texas
Gulf Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest
National

Cultivated Cropland Cultivated Cropland
Loss on Acres
Loss on Acres
Exceeding Threshold Meeting Threshold Exceeding Threshold Meeting Threshold
Acres
Acres
Tons
Tons
Percent
Percent
Percent
Percent
(1,000s)
(1,000s)
(1,000s)
(1,000s)
CEAP I
7,601

53

6,794

47

254

83

51

17

1,553
3,806

35
41

2,894
5,506

65
59

86
98

86
73

14
37

14
27

10,256

47

11,560

53

242

75

81

25

32,828
3,404
4,746
2,545
1,939
5,036
1,068
74,779

27
47
10
18
32
8
37
24

87,306
3,786
43,674
11,465
4,196
59,301
1,802
238,286
CEAP II

73
53
90
82
68
92
63
76

785
123
133
111
79
173
74
2,159

61
84
56
80
81
61
95
69

498
23
105
28
18
112
4
971

39
16
44
20
19
39
5
31

8,260

60

5,565

40

254

87

39

13

1,311
5,055

34
50

2,602
5,111

66
50

70
145

87
81

10
34

13
19

9,886

47

11,030

53

273

79

74

21

38,371
3,769
9,988
2,684
2,045
6,784
764
88,914

31
50
20
20
40
11
24
28

84,925
3,828
41,142
10,754
3,062
55,948
2,419
226,389

69
50
80
80
60
89
76
72

1,025
126
285
115
76
202
29
2,601

68
83
69
85
81
65
89
73

491
25
128
21
17
108
4
949

32
17
31
15
19
35
11
27

140

Conservation Effects Assessment Project

Table A-20. Soluble Phosphorus Relative to Threshold by Region, CEAP I and CEAP II
Region

Atlantic and Gulf Coastal
Plains
California Coastal
East Central
Lower Mississippi and Texas
Gulf Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest
National
Atlantic and Gulf Coastal
Plains
California Coastal
East Central
Lower Mississippi and Texas
Gulf Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest
National

Cultivated Cropland Cultivated Cropland
Loss on Acres
Loss on Acres
Exceeding Threshold Meeting Threshold Exceeding Threshold Meeting Threshold
Acres
Acres
Tons
Tons
Percent
Percent
Percent
Percent
(1,000s)
(1,000s)
(1,000s)
(1,000s)
CEAP I
10,820

75

3,575

25

6

91

1

9

285
6,004

6
64

4,161
3,309

94
36

1
3

74
85

0.4
1

26
15

14,634

67

7,182

33

10

92

1

8

31,059
4,328
468
1,351
2,231
1,297
432
72,909

26
60
1
10
36
2
15
23

89,074
2,862
47,953
12,659
3,903
63,039
2,439
240,156
CEAP II

74
40
99
90
64
98
85
77

18
3
0.2
1
1
1
0.4
45

63
85
10
68
74
28
77
71

11
0.5
2
0.4
0.4
2
0
18

37
15
90
32
26
72
23
29

9,527

69

4,297

31

5

88

1

12

665
7,486

17
74

3,248
2,680

83
26

1
4

80
90

0.2
0.5

20
10

16,233

78

4,683

22

11

94

1

6

40,064
4,478
748
877
2,586
1,405
292
84,361

32
59
1
7
51
2
9
27

83,232
3,119
50,382
12,561
2,521
61,327
2,891
230,942

68
41
99
93
49
98
91
73

25
2
0.3
1
2
1
0
51

69
83
12
58
81
22
88
73

11
1
2
0.4
0.3
2
0.1
19

31
17
88
42
19
78
12
27

Conservation Practices on Cultivated Cropland

141

Table A-21. Soil Carbon Relative to Threshold by Region, CEAP I and CEAP II
Region
Atlantic and Gulf Coastal Plains
California Coastal
East Central
Lower Mississippi and Texas Gulf
Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest
National

Cultivated Cropland Exceeding
Threshold
Acres (1000)
Percent
CEAP I
1,494
10
1,439
32
1,150
12

Cultivated Cropland Meeting
Threshold
Acres (1000)
Percent
12,900
3,007
8,162

90
68
88

2,685

12

19,130

88

15,542
1,361
10,883
2,925
1,283
10,221
720
49,703

13
19
22
21
21
16
25
16

104,592
5,830
37,537
11,085
4,852
54,116
2,150
263,362

87
81
78
79
79
84
75
84

2,083
1,514
1,381

15
39
14

11,742
2,398
8,785

85
61
86

2,966

14

17,949

86

15,826
1,543
10,146
1,875
1,514
8,860
802
48,511

13
20
20
14
30
14
25
15

107,470
6,054
40,985
11,564
3,593
53,872
2,381
266,792

87
80
80
86
70
86
75
85

CEAP II
Atlantic and Gulf Coastal Plains
California Coastal
East Central
Lower Mississippi and Texas Gulf
Coast
North Central and Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and Central Plains
Southwest
National

142

Conservation Effects Assessment Project

Table A-22. Sediment Management on Cultivated Cropland by Region, CEAP I and CEAP II
Region

Atlantic and Gulf
Coastal Plains
California
Coastal
East Central
Lower
Mississippi and
Texas Gulf
North Central and
Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and
Central Plains
Southwest
National

Low
Percent
Acres
Regional
(1,000s)
Acres

Sediment Management Level
Moderate
Moderately High
Percent
Percent
Acres
Acres
Regional
Regional
(1,000s)
(1,000s)
Acres
Acres
CEAP I

High
Percent
Acres
Regional
(1,000s)
Acres

4,879

34

6,929

48

2,053

14

534

4

2,334
842

52
9

1,597
5,101

36
55

35
2,594

1
28

481
775

11
8

8,954

41

10,382

48

2,324

11

155

1

23,705
1,584
12,113
5,380
1,410

20
22
25
38
23

55,270
3,879
24,328
6,178
3,574

46
54
50
44
58

34,032
1,535
11,592
2,159
1,140

28
21
24
15
19

7,126
192
386
294
10

6
3
1
2
0

14,549
1,159
76,910

23
40
25

37,183
1,502
155,923

58
52
50

12,226
209
69,900

19
7
22

378
0
10,332

1
0
3

CEAP II
Atlantic and Gulf
Coastal Plains
California
Coastal
East Central
Lower
Mississippi and
Texas Gulf
North Central and
Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and
Central Plains
Southwest
National

2,924

21

7,511

54

2,600

19

790

6

1,364
491

35
5

2,131
5,029

54
49

418
3,579

11
35

0
1,067

0
10

7,187

34

10,029

48

3,150

15

550

3

13,343
1,007
9,217
2,988
971

11
13
18
22
19

48,244
3,215
26,912
5,268
2,470

39
42
53
39
48

45,138
2,618
12,921
4,405
1,151

37
34
25
33
23

16,570
756
2,081
777
516

13
10
4
6
10

8,108
1,186
48,787

13
37
15

28,861
1,540
141,210

46
48
45

23,061
449
99,490

37
14
32

2,701
8
25,816

4
0
8

Conservation Practices on Cultivated Cropland

143

Table A-23. Nitrogen Management on Cultivated Cropland by Region, CEAP I and CEAP II
Low
Region

Atlantic and Gulf
Coastal Plains
California Coastal
East Central
Lower Mississippi
and Texas Gulf
Coast
North Central and
Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and
Central Plains
Southwest
National
Atlantic and Gulf
Coastal Plains
California Coastal
East Central
Lower Mississippi
and Texas Gulf
Coast
North Central and
Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and
Central Plains
Southwest
National

Nitrogen Management Level
Moderate
Moderately High
Percent
Percent
Acres
Acres
Regional
Regional
(1,000s)
(1,000s)
Acres
Acres
CEAP I

High
Percent
Acres
Regional
(1,000s)
Acres

Acres
(1,000s)

Percent
Regional
Acres

3,279

23

973

7

5,539

38

4,603

32

2,215
2,918

50
31

142
571

3
6

857
3,789

19
41

1,233
2,034

28
22

6,584

30

1,796

8

6,098

28

7,338

34

16,191

13

15,276

13

46,315

39

42,352

35

1,957
2,174
3,303
1,531

27
4
24
25

427
772
267
576

6
2
2
9

2,680
13,038
2,899
2,309

37
27
21
38

2,127
32,436
7,541
1,719

30
67
54
28

7,293

11

1,275

2

21,963

34

33,805

53

1,176
48,620

41
16

139
22,213

5
7
CEAP II

737
106,224

26
34

819
136,007

29
43

2,994

22

907

7

6,868

50

3,057

22

1,969
3,734

50
37

235
524

6
5

863
4,427

22
44

846
1,482

22
15

7,321

35

766

4

6,088

29

6,741

32

25,013

20

21,158

17

47,757

39

29,368

24

2,345
5,547
3,054
1,343

31
11
23
26

463
1,505
406
584

6
3
3
11

3,176
19,936
3,651
1,900

42
39
27
37

1,612
24,143
6,327
1,281

21
47
47
25

8,784

14

2,467

4

27,352

44

24,128

38

1,176
63,279

37
20

206
29,220

6
9

937
122,954

29
39

864
99,850

27
32

144

Conservation Effects Assessment Project

Table A-24. Phosphorus Management on Cultivated Cropland by Region, CEAP I and CEAP II
Low
Region

Atlantic and Gulf
Coastal Plains
California
Coastal
East Central
Lower
Mississippi and
Texas Gulf
North Central and
Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and
Central Plains
Southwest
National
Atlantic and Gulf
Coastal Plains
California
Coastal
East Central
Lower
Mississippi and
Texas Gulf
North Central and
Midwest
Northeast
Northern Plains
Northwest
South Central
Southern and
Central Plains
Southwest
National

Phosphorus Management Level
Moderate
Moderately High
Percent
Percent
Acres
Acres
Regional
Regional
(1,000s)
(1,000s)
Acres
Acres
CEAP I

High
Percent
Acres
Regional
(1,000s)
Acres

Acres
(1,000s)

Percent
Regional
Acres

1,667

12

2,884

20

2,628

18

7,215

50

802

18

713

16

124

3

2,808

63

1,417

15

2,975

32

1,490

16

3,430

37

805

4

2,642

12

4,330

20

14,038

64

7,000

6

20,477

17

25,112

21

67,545

56

1,420
202
1,175
182

20
0
8
3

1,298
1,218
1,037
451

18
3
7
7

651
2,889
1,040
1,296

9
6
7
21

3,821
44,111
10,758
4,205

53
91
77
69

954

1

3,058

5

7,215

11

53,111

83

521
16,146

18
5

377
37,130

312
47,086

11
15

1,660
212,703

58
68

1,762

13

2,492

18

3,716

27

5,856

42

739

19

852

22

376

10

1,946

50

2,252

22

3,317

33

2,105

21

2,493

25

1,371

7

3,974

19

4,120

20

11,451

55

10,460

8

33,569

27

24,504

20

54,763

44

1,226
1,072
1,342
375

16
2
10
7

1,613
3,703
880
774

21
7
7
15

1,257
5,353
1,128
951

17
10
8
19

3,501
41,002
10,089
3,008

46
80
75
59

1,994

3

5,330

8

9,553

15

45,855

73

550
23,140

17
7

400
56,902

13
18

486
53,549

15
17

1,748
181,711

55
58

13
12
CEAP II

Conservation Practices on Cultivated Cropland

145

Table A-25. Sediment Management and Soil Vulnerability Index—Runoff (SVI-R) by Region, CEAP I and
CEAP II
Region

SVI-R

Sediment
Management Level

Atlantic and Gulf Coastal Plains
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low
California Coastal
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low

CEAP I
Acres
(1,000s)

Percent

180
49
99
32
1,124
62
173
685
204
1,976
30
389
934
624
11,115
442
1,443
5,211
4,019
50
50
1,102
8
236
858
3,295
481
27
1,361
1,426

CEAP II
Count

Acres
(1,000s)

Percent

Count

1
27
55
18
8
5
15
61
18
14
1
20
47
32
77
4
13
47
36

15
4
7
4
122
9
16
77
20
197
4
27
99
67
956
30
116
485
325

176
36
24
64
51
1,461
190
272
712
286
2,932
226
557
1,629
519
9,256
338
1,746
5,105
2,067

1
20
14
37
29
11
13
19
49
20
21
8
19
56
18
67
4
19
55
22

15
2
4
7
2
101
8
18
59
16
159
10
36
82
31
489
36
111
246
96

1
100
25
1
21
78
74
15
1
41
43

101
44
57
174
43
103
27
647
326
320
2,992

3
43
57
4
25
59
16
17
50
50
76
11
55
34

4

2
2
25
1
10
14
84
1
2
45
36

331
1,645
1,017

3
1
8
2
4
2
28
16
12
167
8
106
53

146

Conservation Effects Assessment Project

Table A-25. Sediment Management and Soil Vulnerability Index—Runoff (SVI-R) by Region, CEAP I and
CEAP II—Cont.
Region

SVI-R

Sediment
Management Level

East Central
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low
Lower Mississippi and Texas Gulf Coast
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low

CEAP I
Acres
(1,000s)

Percent

1,629
118
502
928
81
2,737
245
956
1,264
271
1,347
188
374
668
117
3,600
224
761
2,241
374
419
3
173
231
12
2,053
29
745
855
424
11,941
57
741
5,742
5,402
7,402
66
666
3,553
3,116

CEAP II
Count

Acres
(1,000s)

Percent

Count

17
7
31
57
5
29
9
35
46
10
14
14
28
50
9
39
6
21
62
10

168
7
56
94
11
299
25
108
131
35
116
12
32
61
11
331
20
78
195
38

2,250
396
812
986
57
2,982
196
1,348
1,305
132
2,085
242
570
1,164
108
2,849
232
849
1,574
193

22
18
36
44
3
29
7
45
44
4
21
12
27
56
5
28
8
30
55
7

172
29
62
75
6
215
14
97
96
8
136
21
40
68
7
217
16
70
115
16

2
1
41
55
3
9
1
36
42
21
55
0
6
48
45
34
1
9
48
42

86
1
38
43
4
255
8
96
112
39
882
7
69
423
383
597
9
68
310
210

590
64
279
220
27
2,117
183
752
922
261
7,786
148
776
3,611
3,251
10,423
155
1,344
5,276
3,648

3
11
47
37
5
10
9
36
44
12
37
2
10
46
42
50
1
13
51
35

51
4
27
18
2
161
12
58
73
18
485
9
55
232
189
693
12
98
352
231

Conservation Practices on Cultivated Cropland

147

Table A-25. Sediment Management and Soil Vulnerability Index—Runoff (SVI-R) by Region, CEAP I and
CEAP II—Cont.
Region

SVI-R

Sediment
Management Level

North Central and Midwest
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low
Northeast
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low

CEAP I
Acres
(1,000s)

Percent

15,178
2,233
7,038
5,111
795
23,585
1,550
8,262
10,562
3,211
19,444
1,010
4,938
8,909
4,587
61,927
2,333
13,794
30,688
15,112
1,834
63
589
984
198
1,913
43
405
975
489
1,014
8
92
625
289
2,429
78
448
1,295
608

CEAP II
Count

Acres
(1,000s)

Percent

Count

13
15
46
34
5
20
7
35
45
14
16
5
25
46
24
52
4
22
50
24

1,199
152
567
414
66
1,737
99
631
773
234
1,232
54
308
583
287
3,897
149
901
1,929
918

19,377
5,076
10,175
3,704
423
24,668
4,238
10,764
8,129
1,536
13,923
1,260
4,667
6,729
1,267
65,329
5,996
19,533
29,683
10,118

16
26
53
19
2
20
17
44
33
6
11
9
34
48
9
53
9
30
45
15

687
170
354
144
19
870
148
393
286
43
484
50
165
223
46
2,164
197
669
984
314

26
3
32
54
11
27
2
21
51
26
14
1
9
62
28
34
3
18
53
25

238
10
79
124
25
241
11
56
116
58
107
1
17
63
26
302
11
63
153
75

2,426
336
1,023
735
333
2,116
99
695
1,077
244
950
61
245
562
83
2,105
260
656
842
347

32
14
42
30
14
28
5
33
51
12
13
6
26
59
9
28
12
31
40
17

204
31
96
62
15
178
12
67
78
21
89
7
29
44
9
195
22
60
88
25

148

Conservation Effects Assessment Project

Table A-25. Sediment Management and Soil Vulnerability Index—Runoff (SVI-R) by Region, CEAP I and
CEAP II—Cont.
Region

SVI-R

Sediment
Management Level

Northern Plains
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low

CEAP I
Acres
(1,000s)

Percent

3,128
33
957
1,779
359
11,155
60
3,669
5,156
2,270
8,232
41
1,557
3,710
2,924
25,905
252
5,409
13,683
6,560
3,296
42
850
1,403
1,001
3,183
77
363
1,389
1,353
558
31
83
269
175
6,973
144
861
3,117
2,851

CEAP II
Count

Acres
(1,000s)

Percent

Count

6
1
31
57
11
23
1
33
46
20
17
1
19
45
36
54
1
21
53
25

110
1
34
62
13
331
3
116
149
63
236
1
48
114
73
841
10
174
452
205

2,990
345
974
1,518
152
9,857
648
3,817
5,097
295
8,896
229
1,899
5,755
1,013
29,388
859
6,230
14,543
7,757

6
12
33
51
5
19
7
39
52
3
17
3
21
65
11
57
3
21
49
26

87
10
27
46
4
242
13
87
131
11
201
7
47
122
25
682
21
152
362
147

24
1
26
43
30
23
2
11
44
43
4
6
15
48
31
50
2
12
45
41

227
3
62
100
62
233
2
23
105
103
63
1
4
31
27
525
7
67
217
234

3,858
372
1,633
1,478
374
3,436
173
1,113
1,273
876
779
231
347
201
5,366
232
1,428
2,170
1,537

29
10
42
38
10
26
5
32
37
26
6
30
45
26
40
4
27
40
29

128
8
70
43
7
134
6
43
49
36
32
8
17
7
253
11
65
106
71

Northwest
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low

Conservation Practices on Cultivated Cropland

149

Table A-25. Sediment Management and Soil Vulnerability Index—Runoff (SVI-R) by Region, CEAP I and
CEAP II—Cont.
Region

SVI-R

Sediment
Management Level

South Central
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low
Southern and Central Plains
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low

CEAP I
Acres
(1,000s)

Percent

20
20
1,657
405
998
255
2,458
5
472
1,407
574
1,999
5
264
1,149
581
1,393
24
515
775
78
6,018
104
1,678
3,680
557
6,194
32
1,147
3,757
1,258
50,732
219
8,886
28,971
12,656

CEAP II
Count

Acres
(1,000s)

Percent

Count

0
100
27
24
60
15
40
0
19
57
23
33
0
13
57
29

2
2
65
15
41
9
88
1
14
49
24
77
1
11
40
25

211
31
91
49
40
1,667
113
586
766
202
1,898
198
218
947
535
1,331
174
255
708
193

4
15
43
23
19
33
7
35
46
12
37
10
11
50
28
26
13
19
53
15

8
1
4
2
1
85
5
37
34
9
104
12
14
45
33
82
4
17
49
12

2
2
37
56
6
9
2
28
61
9
10
1
19
61
20
79
0
18
57
25

66
1
22
37
6
253
4
70
155
24
244
1
43
147
53
2,052
10
368
1,125
549

1,539
228
739
538
34
9,340
597
4,748
3,781
214
4,701
112
1,839
2,126
624
47,151
1,764
15,736
22,415
7,236

2
15
48
35
2
15
6
51
40
2
7
2
39
45
13
75
4
33
48
15

46
3
24
18
1
261
18
123
112
8
157
6
61
70
20
1,339
49
443
660
187

150

Conservation Effects Assessment Project

Table A-25. Sediment Management and Soil Vulnerability Index—Runoff (SVI-R) by Region, CEAP I and
CEAP II—Cont.
Region

SVI-R

Sediment
Management Level

CEAP I
Acres
(1,000s)

Percent

68
38
30
247
58
74
115
269
15
162
92
2,287
136
1,229
922

2
56
44
9
24
30
47
9
6
60
34
80
6
54
40

CEAP II
Count

Acres
(1,000s)

Percent

Count

6
4
2
19
3
8
8
16
1
10
5
149
9
58
82

14
14
349
127
113
109
185
73
112
2,636
8
322
1,341
965

0
100
11
36
32
31
6
39
61
83
0
12
51
37

1
1
12
3
7
2
12
6
6
110
1
13
53
43

Southwest
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low

Conservation Practices on Cultivated Cropland

151

Table A-26. Nitrogen Management and Soil Vulnerability Index—Leaching (SVI-L) by Region, CEAP I and
CEAP II
Region

SVI-L
Rating

Nitrogen Management
Level

Atlantic and Gulf Coastal Plains
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low
California Coastal
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low

CEAP I
Acres
(1,000s)

Percent

6,694
2,007
2,668
312
1,707
3,661
1,233
1,338
310
781
3,799
1,308
1,403
351
737
240
56
130
54

47
30
40
5
25
25
34
37
8
21
26
34
37
9
19
2
23
54
0
22

621
163
152
14
291
388
36
59
30
263
2,278
912
438
63
865
1,160
122
208
34
796

14
26
25
2
47
9
9
15
8
68
51
40
19
3
38
26
11
18
3
69

CEAP II
Count

154
210
25
101
107
127
28
61
136
185
32
99
6
14
0
5

8
7
1
10
2
1
1
3
8
9
1
22
3
8
2
25

Acres
(1,000s)

Percent

4,069
967
1,954
332
817
4,760
1,086
2,305
353
1,016
3,938
809
2,045
189
895
1,058
195
563
33
267

29
24
48
8
20
34
23
48
7
21
28
21
52
5
23
8
18
53
3
25

1,369
219
380
79
691
386
66
108
51
161
1,543
371
218
105
849
615
191
156
269

35
16
28
6
50
10
17
28
13
42
39
24
14
7
55
16
31
25
0
44

Count

49
107
18
54
48
106
14
38
55
118
11
73
13
36
3
21

12
33
5
41
3
5
1
15
12
10
5
41
4
7
0
13

152

Conservation Effects Assessment Project

Table A-26. Nitrogen Management and Soil Vulnerability Index—Leaching (SVI-L) by Region, CEAP I and
CEAP II—Cont.
Region

SVI-L
Rating

Nitrogen Management
Level

East Central
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low
Lower Mississippi and Texas Gulf Coast
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low

CEAP I
Acres
(1,000s)

Percent

1,756
496
656
129
475
705
192
279
73
161
6,728
1,306
2,785
362
2,275
123
40
69
7
8

19
28
37
7
27
8
27
40
10
23
72
19
41
5
34
1
32
56
6
6

4,463
1,529
851
266
1,816
11,773
4,242
3,471
1,060
3,000
4,772
1,386
1,363
380
1,643
808
180
413
89
126

20
34
19
6
41
54
36
29
9
25
22
29
29
8
34
4
22
51
11
16

CEAP II
Count

42
58
12
47
20
31
7
17
134
279
38
214
4
9
1
1

103
79
20
130
316
280
57
253
152
173
57
176
7
9
3
5

Acres
(1,000s)

Percent

1,081
119
469
111
382
1,339
115
715
68
441
5,980
955
2,405
277
2,343
1,767
294
837
68
568

11
11
43
10
35
13
9
53
5
33
59
16
40
5
39
17
17
47
4
32

6,374
2,192
1,932
168
2,083
7,781
3,034
1,981
255
2,511
4,258
888
1,324
183
1,862
2,502
626
851
159
865

30
34
30
3
33
37
39
25
3
32
20
21
31
4
44
12
25
34
6
35

Count

12
35
7
23
12
50
5
31
58
183
25
160
23
62
8
46

141
130
12
130
180
135
14
155
86
104
12
143
47
44
9
48

Conservation Practices on Cultivated Cropland

153

Table A-26. Nitrogen Management and Soil Vulnerability Index—Leaching (SVI-L) by Region, CEAP I and
CEAP II—Cont.
Region

SVI-L
Rating

Nitrogen Management
Level

North Central and Midwest
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low
Northeast
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low

CEAP I
Acres
(1,000s)

Percent

42,935
15,473
15,642
5,870
5,950
20,061
6,880
8,059
2,897
2,225
54,003
18,602
21,340
6,241
7,820
3,133
1,397
1,273
267
196

36
36
36
14
14
17
34
40
14
11
45
34
40
12
14
3
45
41
9
6

1,055
457
282
29
286
692
268
255
48
120
5,304
1,335
2,095
348
1,527
140
66
48
1
24

15
43
27
3
27
10
39
37
7
17
74
25
39
7
29
2
47
34
1
17

CEAP II
Count

1018
1015
349
369
447
509
162
142
1355
1518
406
542
92
100
24
17

46
33
6
32
33
29
6
16
136
264
42
223
9
7
1
5

Acres
(1,000s)

Percent

49,186
11,756
18,278
9,623
9,529
14,715
3,975
5,582
2,405
2,752
48,928
10,783
19,592
7,331
11,221
10,467
2,853
4,304
1,798
1,511

40
24
37
20
19
12
27
38
16
19
40
22
40
15
23
8
27
41
17
14

1,167
229
605
116
216
1,026
290
469
53
214
3,746
601
1,497
202
1,447
1,658
492
605
93
468

15
20
52
10
19
14
28
46
5
21
49
16
40
5
39
22
30
36
6
28

Count

378
608
293
311
127
194
87
91
397
727
261
397
85
144
60
45

18
46
6
25
27
40
6
21
56
140
21
147
32
37
11
33

154

Conservation Effects Assessment Project

Table A-26. Nitrogen Management and Soil Vulnerability Index—Leaching (SVI-L) by Region, CEAP I and
CEAP II—Cont.
Region

SVI-L
Rating

Nitrogen Management
Level

Northern Plains
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low

CEAP I
Acres
(1,000s)

Percent

12,828
7,623
4,058
362
785
4,362
2,945
1,080
151
187
28,080
19,703
7,060
259
1,057
3,150
2,165
841
144

26
59
32
3
6
9
67
25
3
4
58
70
25
1
4
7
69
27
0
5

3,024
1,573
554
111
785
651
248
91
11
301
9,866
5,498
2,186
132
2,050
468
222
67
12
167

22
52
18
4
26
5
38
14
2
46
70
56
22
1
21
3
47
14
3
36

CEAP II
Count

227
128
9
25
77
33
4
4
596
251
8
41
71
35
0
9

Acres
(1,000s)

Percent

13,880
6,114
5,257
460
2,049
5,659
2,817
2,061
172
608
27,756
13,557
10,791
729
2,679
3,835
1,655
1,826
143
210

27
44
38
3
15
11
50
36
3
11
54
49
39
3
10
7
43
48
4
5

2,269
887
550
93
738
259
71
86
52
50
10,244
5,141
2,770
238
2,094
667
228
244
23
172

17
39
24
4
33
2
27
33
20
19
76
50
27
2
20
5
34
37
4
26

Count

118
108
9
49
58
44
3
11
332
284
20
70
43
51
3
9

Northwest
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low

107
49
6
76
14
14
3
29
334
154
15
209
15
7
2
14

44
30
6
33
6
9
3
5
167
102
12
101
11
10
1
7

Conservation Practices on Cultivated Cropland

155

Table A-26. Nitrogen Management and Soil Vulnerability Index—Leaching (SVI-L) by Region, CEAP I and
CEAP II—Cont.
Region

SVI-L
Rating

Nitrogen Management
Level

South Central
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low
Southern and Central Plains
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low

CEAP I
Acres
(1,000s)

Percent

836
411
146
31
248
1,290
390
525
61
314
1,689
305
848
40
496
2,320
613
790
444
473

14
49
17
4
30
21
30
41
5
24
28
18
50
2
29
38
26
34
19
20

16,869
7,748
6,460
215
2,446
2,330
948
936
46
398
39,522
22,177
12,544
889
3,912
5,616
2,932
2,023
125
536

26
46
38
1
14
4
41
40
2
17
61
56
32
2
10
9
52
36
2
10

CEAP II
Count

11
6
2
7
16
27
3
17
17
35
3
15
21
24
10
18

340
260
11
130
43
41
4
16
835
484
42
183
120
81
4
21

Acres
(1,000s)

Percent

464
115
123
109
116
1,038
357
269
127
285
1,359
417
632
76
234
2,246
391
875
271
708

9
25
26
24
25
20
34
26
12
27
27
31
47
6
17
44
17
39
12
32

10,784
3,638
4,440
574
2,132
1,708
587
764
26
330
45,308
17,728
20,000
1,690
5,890
4,932
2,175
2,148
177
432

17
34
41
5
20
3
34
45
2
19
72
39
44
4
13
8
44
44
4
9

Count

6
8
5
9
18
19
3
18
24
33
3
17
19
50
13
34

98
145
20
75
15
29
1
15
454
511
60
198
79
78
7
18

156

Conservation Effects Assessment Project

Table A-26. Nitrogen Management and Soil Vulnerability Index—Leaching (SVI-L) by Region, CEAP I and
CEAP II—Cont.
Region

SVI-L
Rating

Nitrogen Management
Level

CEAP I
Acres
(1,000s)

Percent

432
80
167
52
132
142
76
66
2,103
637
481
85
899
194
26
22
1
145

15
19
39
12
31
5
53
47
0
0
73
30
23
4
43
7
13
11
<1
75

CEAP II
Count

Acres
(1,000s)

Percent

638
287
170
68
114
63
6
42
15
2,356
560
694
97
1,005
126
17
67
42

20
45
27
11
18
2
0
10
67
23
74
24
29
4
43
4
14
53
0
33

Count

Southwest
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low

6
7
2
10
5
4
0
0
40
37
6
58
2
3
1
9

14
11
4
8
0
1
1
2
22
26
4
34
3
2
0
3

Conservation Practices on Cultivated Cropland

157

Table A-27. Phosphorus Management and Soil Vulnerability Index—Runoff (SVI-R) by Region, CEAP I and
CEAP II
Region

SVI-R

Phosphorus
Management
Level

Atlantic and Gulf Coastal Plains
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low
California Coastal
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low

CEAP I
Acres
(1,000s)

Percent

180
107
20
13
40
1,124
510
251
261
102
1,976
1,084
320
404
168
11,115
5,514
2,037
2,206
1,357

1
59
11
7
22
8
45
22
23
9
14
55
16
20
9
77
50
18
20
12

50
21
29
1,102
535
24
513
29
3,295
2,273
100
178
745

0
0
0
0
0
1
0
0
43
57
25
49
2
47
3
74
69
3
5
23

CEAP II
Count

8
2
2
3
47
29
34
12
118
31
35
13
512
180
197
67

0
0
0
0
0
0
1
1
16
2
6
1
51
6
12
15

Acres
(1,000s)

Percent

176
77
45
40
14
1,461
499
374
371
217
2,932
1,032
1,071
534
295
9,256
4,248
2,226
1,547
1,235

1
44
25
23
8
11
34
26
25
15
21
35
37
18
10
67
46
24
17
13

101
44
57
174
129
10
35
647
265
34
167
180
2,992
1,508
342
618
524

3
43
0
57
0
4
74
0
6
20
17
41
5
26
28
76
50
11
21
18

Count

6
4
3
2
33
29
26
13
71
47
25
16
237
116
92
44

3
0
1
0
4
0
1
3
11
2
8
7
81
20
38
28

158

Conservation Effects Assessment Project

Table A-27. Phosphorus Management and Soil Vulnerability Index—Runoff (SVI-R) by Region, CEAP I and
CEAP II—Cont.
Region

SVI-R

Phosphorus
Management
Level

CEAP I
Acres
(1,000s)

Percent

1,629
580
173
640
236
2,737
769
509
1,042
416
1,347
576
168
372
230
3,600
1,504
640
921
535

17
36
11
39
14
29
28
19
38
15
14
43
13
28
17
39
42
18
26
15

419
157
141
97
24
2,053
895
417
568
173
11,941
8,273
2,449
904
315
7,402
4,713
1,323
1,073
292

2
37
34
23
6
9
44
20
28
8
55
69
21
8
3
34
64
18
14
4

CEAP II
Count

Acres
(1,000s)

Percent

2,250
416
508
705
622
2,982
660
592
1,113
617
2,085
642
444
491
508
2,849
774
562
1,007
506

22
18
23
31
28
29
22
20
37
21
21
31
21
24
24
28
27
20
35
18

590
69
110
350
61
2,117
565
517
858
177
7,786
4,728
1,512
1,068
478
10,423
6,089
1,981
1,698
655

3
12
19
59
10
10
27
24
41
8
37
61
19
14
6
50
58
19
16
6

Count

East Central
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low
Lower Mississippi and Texas Gulf Coast
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low

63
17
61
27
83
53
118
45
47
14
38
17
130
52
98
51

22
29
28
7
81
61
83
30
585
187
86
24
363
121
87
26

37
40
53
42
41
43
84
47
32
32
41
31
58
43
76
40

10
10
25
6
46
36
64
15
298
91
69
27
395
149
109
40

Conservation Practices on Cultivated Cropland

159

Table A-27. Phosphorus Management and Soil Vulnerability Index—Runoff (SVI-R) by Region, CEAP I and
CEAP II—Cont.
Region

SVI-R

Phosphorus
Management
Level

North Central and Midwest
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low

CEAP I
Acres
(1,000s)

Percent

15,178
7,597
3,068
3,390
1,123
23,585
12,610
4,740
4,562
1,674
19,444
11,278
4,233
3,040
894
61,927
36,061
13,072
9,486
3,309

13
50
20
22
7
20
53
20
19
7
16
58
22
16
5
52
58
21
15
5

1,834
968
167
358
342
1,913
892
284
346
391
1,014
603
46
194
171
2,429
1,358
154
399
517

26
53
9
19
19
27
47
15
18
20
14
59
5
19
17
34
56
6
16
21

CEAP II
Count

607
248
260
84
960
324
338
115
718
254
197
63
2349
777
573
198

Acres
(1,000s)

Percent

19,377
7,540
3,417
6,930
1,489
24,668
10,554
4,210
7,261
2,643
13,923
6,154
2,767
3,664
1,338
65,329
30,515
14,111
15,713
4,990

16
39
18
36
8
20
43
17
29
11
11
44
20
26
10
53
47
22
24
8

2,426
995
381
608
443
2,116
981
360
442
333
950
553
178
103
117
2,105
972
339
461
333

32
41
16
25
18
28
46
17
21
16
13
58
19
11
12
28
46
16
22
16

Count

267
120
244
56
364
160
254
92
216
96
126
46
999
469
529
167

Northeast
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low

116
24
49
49
104
41
48
48
58
5
23
21
157
28
60
57

81
36
50
37
73
29
45
31
51
18
11
9
91
33
38
33

160

Conservation Effects Assessment Project

Table A-27. Phosphorus Management and Soil Vulnerability Index—Runoff (SVI-R) by Region, CEAP I and
CEAP II—Cont.
Region

SVI-R

Phosphorus
Management
Level

CEAP I
Acres
(1,000s)

Percent

3,128
2,937
191
11,155
10,739
327
90
8,232
7,458
553
221
25,905
22,977
1,818
907
202

6
94
6
0
0
23
96
3
1
0
17
91
7
3
0
54
89
7
4
1

3,296
3,046
114
66
71
3,183
2,631
128
226
197
558
329
72
83
74
6,973
4,752
726
662
833

24
92
3
2
2
23
83
4
7
6
4
59
13
15
13
50
68
10
9
12

CEAP II
Count

Acres
(1,000s)

Percent

2,990
2,433
300
207
50
9,857
8,499
796
360
201
8,896
7,172
910
719
95
29,388
22,898
3,347
2,418
725

6
81
10
7
2
19
86
8
4
2
17
81
10
8
1
57
78
11
8
2

3,858
3,530
138
90
100
3,436
2,631
255
218
332
779
495
190
38
57
5,366
3,434
546
533
853

29
91
4
2
3
26
77
7
6
10
6
63
24
5
7
40
64
10
10
16

Count

Northern Plains
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low

105
5
0
0
309
18
4
0
211
17
8
0
738
60
32
11

70
11
5
1
200
25
10
7
160
17
21
3
517
83
61
21

Northwest
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low

202
10
6
9
183
12
18
20
28
9
13
13
334
50
69
72

114
7
5
2
93
13
12
16
21
7
2
2
157
35
31
30

Conservation Practices on Cultivated Cropland

161

Table A-27. Phosphorus Management and Soil Vulnerability Index—Runoff (SVI-R) by Region, CEAP I and
CEAP II—Cont.
Region

SVI-R

Phosphorus
Management
Level

CEAP I
Acres
(1,000s)

Percent

20
10
10
1,657
990
541
74
53
2,458
1,853
408
167
30
1,999
1,352
337
211
99

<1
49
51
0
0
27
60
33
4
3
40
75
17
7
1
33
68
17
11
5

1,393
1,187
113
38
55
6,018
4,918
761
264
75
6,194
5,098
770
318
8
50,732
41,908
5,570
2,438
816

2
85
8
3
4
9
82
13
4
1
10
82
12
5
<1
79
83
11
5
2

CEAP II
Count

Acres
(1,000s)

Percent

211
63
70
42
36
1,667
919
289
270
189
1,898
1,247
243
324
85
1,331
779
349
138
65

4
30
33
20
17
33
55
17
16
11
37
66
13
17
4
26
59
26
10
5

1,539
1,046
317
96
80
9,340
6,912
1,451
846
131
4,701
3,755
581
208
157
47,151
34,142
7,203
4,181
1,625

2
68
21
6
5
15
74
16
9
1
7
80
12
4
3
75
72
15
9
3

Count

South Central
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low
Southern and Central Plains
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low

1
1
0
0
38
20
4
3
59
18
9
2
47
17
10
3

57
5
2
2
206
32
12
3
200
31
12
1
1693
214
103
42

2
2
2
2
47
17
15
6
72
15
14
3
51
17
7
7

30
10
4
2
187
40
29
5
123
23
8
3
960
189
142
48

162

Conservation Effects Assessment Project

Table A-27. Phosphorus Management and Soil Vulnerability Index—Runoff (SVI-R) by Region, CEAP I and
CEAP II—Cont.
Region

SVI-R

Phosphorus
Management
Level

CEAP I
Acres
(1,000s)

Percent

68
68
247
205
22
1
19
269
181
8
79
2,287
1,206
289
368
423

2
100
0
0
0
9
83
9
<1
8
9
68
0
3
29
80
53
13
16
19

CEAP II
Count

Acres
(1,000s)

Percent

14
14
349
321
25
1
2
185
115
46
3
21
2,636
1,298
414
396
528

<1
100
0
0
0
11
92
7
<1
<1
6
62
25
2
11
83
49
16
15
20

Count

Southwest
High
High
Moderately High
Moderate
Low
Moderately High
High
Moderately High
Moderate
Low
Moderate
High
Moderately High
Moderate
Low
Low
High
Moderately High
Moderate
Low

6
0
0
0
14
2
1
2
10
0
1
5
91
11
19
28

1
0
0
0
7
3
1
1
6
3
1
2
61
12
17
20

Conservation Practices on Cultivated Cropland

163

APPENDIX 3. MANAGEMENT LEVELS CRITERIA
Throughout the report, cultivated cropland is categorized by the level of sediment, nitrogen, and
phosphorus management being applied to allow comparison of conservation treatment between
the two survey periods. Cultivated cropland acres are placed into one of four management
levels—high, moderately high, moderate, and low. The criteria are based on an Avoid, Control,
and Trap approach to reducing sediment losses, and a Rate, Method, and Timing approach to
reducing nutrient losses from cropland. The following provides an overview of the criteria for
categorizing sediment, nitrogen, and phosphorus management.
Sediment Management Levels:
1. High: At least one practice from each category with no practice counting twice.
a. Avoid:
i. All crops in the rotation are in conservation tillage (continuous no-till or reduced
tillage)
b. Control:
i. At least one structural practice in overland flow or concentrated flow control
categories (e.g., terrace, contouring, or grassed waterway), or
ii. A high biomass conservation crop rotation (i.e., a crop residue score of 2 or
more).
c. Trap:
i. At least one structural practice to trap potential losses (e.g., filter or buffer), or
ii. A field border structural practice with a minimum of 30 feet in width and placed
to intercept flow from cropped area.
2. Moderately High: At least one practice from two of the categories with no practice counting
twice.
a. Avoid:
i. All crops in the rotation are in conservation tillage (continuous no-till or reduced
tillage)
b. Control:
i. At least one structural practice in overland flow or concentrated flow control
categories (e.g., terrace, contouring, or grassed waterway), or
ii. A high biomass conservation crop rotation (i.e., a crop residue score of 2 or
more) if all crops are in conservation tillage.
c. Trap:
i. At least one structural practice to trap potential losses (e.g., filter or buffer), or
ii. If all crops are in conservation tillage, a field border structural practice with a
minimum of 30 feet in width and placed to intercept flow from cropped area can
be substituted for filter or buffer trapping practice.
3. Moderate: At least one practice from any category.
a. Avoid:
i. All crops in the rotation are under conservation tillage (continuous no-till or
reduced tillage),
b. Control:
i. At least one structural practice in overland flow or concentrated flow control
categories (e.g., terrace, contouring, or grassed waterway), or
ii. A high biomass conservation crop rotation (i.e., a crop residue score of 2 or
more).

164

Conservation Effects Assessment Project

c. Trap:
i. At least one trapping practice such as a filter or buffer, or
ii. A Field Border can be substituted if it is minimum of 30 feet in width and
intercepts flow from cropped area.

4. Low:
a. At least one crop in the rotation under conventional tillage, and
b. No avoid, control, or trap practices are applied
Nutrient Management:
For nitrogen and phosphorus management, management levels are based primarily on rate,
method, and timing of nutrient application:
Rate: Four rate classes are based on the average annual per acre nutrient application for the crop
rotation:
1. Nitrogen:
a. Low: Rotational average of 75 pounds or less per acre annually.
b. Moderate: Rotational average of greater than 75 pounds and less than or equal to 90
pounds per acre annually.
c. Moderately High: Rotational average of greater than 90 pounds and less than or equal to
120 pounds per acre annually.
d. High: Rotational average of more than 120 pounds per acre annually.
2. Phosphorus
a. Low: Rotational average of 20 pounds or less per acre annually.
b. Moderate: Rotational average of greater than 20 pounds and less than or equal to 35
pounds per acre annually.
c. Moderately High: Rotational average of greater than 35 pounds and less than or equal to
50 pounds per acre annually.
d. High: Rotational average more than 50 pounds per acre annually

Method: Three method classes are based on the level of incorporation of the applied nutrient for
the crop rotation:
1. All applications are incorporated within 48 hours through tillage, injection, knifing, or banding.
Fertigation is considered incorporation since the water moves the nutrients from surface into
subsurface.
2. Some applications are incorporated within 48 hours.
3. No applications are incorporated within 48 hours.

Post-plant and fall applications to perennials and winter annuals are exempted from the method
assessment. Post-plant applications on actively growing crops with full surface coverage have
very low loss risk through surface and subsurface pathways, especially with late winter/early
spring top dressing of winter annuals (e.g., wheat).
Timing: Two timing classes are based on fall and winter applications (beginning of September
to end of February) for the crop rotation:
1. No fall or winter application. Fall manure applications are considered acceptable for all crops in
the rotation, however, winter manure applications are not acceptable for any crop in the rotation,
including winter annuals and perennials. All non-manure applications are acceptable for winter
annuals and perennials regardless of season.

Conservation Practices on Cultivated Cropland

165

2. At least one fall or winter application.
Nitrogen Management Levels:
High:
i.
Rate class is low, or
ii.
Rate class is moderate, all or some applications are incorporated, and there are no fall or winter
applications.

Moderately High:
i.
Rate class is moderate, or
ii.
Rate class is moderately high, all applications are incorporated, and there are no fall or winter
applications.

Moderate:
i.
Rate class is moderately high, and all or some applications are incorporated.
Low:
Rate class is moderately high, and no applications are incorporated, or
i.
ii.
Rate class is high.
Phosphorus Management Levels:
High:
i.
No phosphorus is applied, or
ii.
Rate class is low, and all applications are incorporated, or
iii.
Rate class is low, some applications are incorporated, and there are no fall or winter applications,
iv.

or
Rate class is moderate, all applications are incorporated, and there are no fall or winter
applications, or
Rate class is low, and all applications are post-plant applications on winter annuals or perennials.

v.
Moderately High:
i.
Rate class is low, some applications are incorporated, and there are fall or winter applications, or
ii.
Rate class is low, and no applications are incorporated, or
iii.
Rate class is moderate, and all applications are incorporated, or
iv. Rate class is moderate, and all applications are post-plant applications on winter annuals or
perennials.

Moderate:
i.
Rate class is moderate, and some or none of the applications are incorporated, or
ii.
Rate class is moderately high, and all applications are incorporated, or
iii.
Rate class is moderately high, and all applications are post-plant applications on winter annuals or
perennials.

Low:
i.
Rate class is moderately high and some or none of the applications are incorporated, or
ii.
Rate class is high.