Supporting Statement - Part B

FIELD CROPS PRODUCTION

OMB No. 0535-0002

B.	COLLECTION OF INFORMATION EMPLOYING STATISTICAL METHODS

1.	Describe (including a numerical estimate) the potential respondent universe and any sampling or other respondent selection method to be used. Data on the number of entities (e.g., establishments, State and local government units, households, or persons) in the universe covered by the collection and in the corresponding sample are to be provided in tabular form for the universe as a whole and for each of the strata in the proposed sample. Indicate expected response rates for the collection as a whole. If the collection has been conducted previously, include the actual response rate achieved during the last collection.

The potential respondent universe is all 2.2 million farmers in the United States, excluding those who have already been selected for the national agricultural probability surveys program, OMB No. 0535-0213. Each Field Office maintains a list of farmers known to grow crops of interest and to represent all crop growing areas within a State. Sample sizes are determined for each crop as shown in Item A-12 table. Telephone follow-up is conducted for any survey which does not reach at least 50 percent response, subject to available funds, to ensure reliable indications. These follow-on surveys are required to cover small or specialty crops that are not adequately represented in our probability surveys.

Cooperative Extension Service agents are the primary respondents for the weekly Crop Progress and Condition Inquiry. Other sources include farmers, FSA county officials, and farm loan representatives of banks serving agricultural areas.

Field Crop Response Rates for 2006

Survey	Sample

Size	Freq	Response Rate %	Survey	Sample

Size	Freq	Response Rate %
Alfalfa/Clover Seed	350	1	88 .5	Sweetpotatoes	1,500	3	78 .2
Dry Beans	6,000	3	76 .4	Tobacco	2,500	5	49 .4
Mint	300	1	76 .0
Oilseeds, special	1,900	1	63 .5	Wheat & Barley Variety	14,000	1	67 .7
Potatoes	4,500	3	70 .9
Sugarbeets	6	4	100 .0	Acreage and Production	300,000	1	56 .8
Sugarcane, Firms	17	6	93 .9
Sunflower, non-oil	2	3	100 .0	Crop Progress	4,000	40	55 .1

2.	Describe the procedures for the collection of information.

The specialty surveys listed in the first part of the table above target commodities that cannot be covered adequately in general purpose surveys. Most are grower surveys using a mail phase with telephone nonresponse followup until a prescribed cutoff date. The sample sizes cited often represent over 50 percent of the sampling population and contain a large number of matched reports from survey to survey. These surveys are coordinated with other collections to avoid duplicate contacts. The sugar and sunflower surveys are a census of all processors using a mail phase with phone followup.

The Wheat and Barley Variety surveys and the Acreage and Production survey obtain the information needed to estimate proportions and averages only. No direct indications or estimates are derived from these data. Official State and U.S. estimates are set from the quarterly Crops/Stocks survey (OMB No. 0535-0213), a national probability survey with full followup. The results of the Variety and Acreage surveys are used to allocate the official estimate into classes (variety) or to geographic subdomains (district and county). These surveys employ a mail phase with phone followup until a prescribed time deadline. Nonreponse followup is directed to achieve sufficient coverage and full followup is not required. Operations selected for the Crops/Stocks probability surveys are excluded from the Acreage survey (to aviod duplicate contacts), however data collected are pooled when computing the proportions and averages. The Crops/Stocks surveys and the 5-year Census of Agriculture (OMB No. 0535-0226) are used to evaluate potential bias.

The Crop Progress surveys are a weekly panel of respondents made up largely of government employees, USDA Extension Agents and USDA Farm Service Agency personnel. It is a quick turnaround (same day) survey using a Web-based instrument. Data are collected by noon and estimates are published by 4:00 pm Eastern Time. No followup is done for these sureveys.

Modes of data collection include original mailing of questionnaires, follow-up mailing of questionnaires to non-respondents, post card reminders, phone follow-up, and limited face to face enumeration in certain situations. The amount of time allotted to collect the data as well as amount of funds available for data collection will be considered when determining the modes to be used on each of the surveys. Each State is responsible for utilizing the resources available to them to maximize the response rates while minimizing the respondent burden and out of pocket expenses.

Questionnaires are mailed to the entire sample/universe. They are returned to the State Field Offices (FOs) and reviewed for reasonableness prior to keying into data processing media for summarization. Questionnaires are summarized by crop reporting districts and the indications weighted for the State based on the relative importance of the commodity in the district.

3.	Describe methods to maximize response rates and to deal with issues of non-
response. The accuracy and reliability of information collected must be shown to be adequate for intended uses. For collections based on sampling. a special justification must be provided for any collection that will not yield "reliable" data that can be generalized to the universe studied.

Since we are relying on the mail for a great deal of data collection for these surveys, it is very important for the respondents to know who NASS is and how we will be using the data that they provide. This is accomplished both by including publicity materials with the questionnaires and sending out survey results to the respondents once the summaries are published. Statisticians within each of the State Offices also attend growers meetings, trade shows, State Fairs, etc., to meet with farmers and answer any questions they have about NASS or the data that is collected.

With the heavy dependence on a mail phase for these surveys, Field Offices are directed to perform sufficient non-response followup to reduce the possible impact of a self-
selecting sample. All samples and estimators are designed to provide unbiased point estimates of the items of interest. Surveys that do not require full followup can only provide approximations of measures of precision. Estimates of proportions and averages have very narrow ranges and standard errors tend to be small given the large sample sizes.

NASS Field Offices constantly monitor responses, particularly for the acreage and production surveys, to ensure adequate coverage for all counties requiring estimation. Targeted non-response follow-up occurs regularly when coverage deficiencies are identified. This involves extensive telephone follow-up in addition to personal enumeration when resources allow.

4.	Describe any tests of procedures or methods to be undertaken.

No testing is done.

5.	Provide the name and telephone number of individuals consulted on statistical aspects of the design and the name of the agency unit, contractor(s), grantee(s), or other person(s) who will actually collect and/or analyze the information for the agency.

Sample size for each State is determined by the Sampling Branch, Census and Survey Division; Branch Chief is William Iwig, (202)720-3895. Sample size for each State is reviewed by the Agency's Statistical Methods Branch; Branch Chief is Dave Aune, (202)720-4008.

Data collection is carried out by NASS Field Offices; Deputy Administrator for Field Operations is Marshall Dantzler, (202)720-8220. Survey data are also reviewed and summarized by the State Field Offices. Publications are released from the State Offices and Headquarters.

March 2007

Revised November 2007

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