Response frequency is generally over 75 percent. Data gathered in all the surveys include types, application, timing, and amounts of fertilizer, pesticides, and other chemicals. In 1993 NASS conducted a survey of subscribers to its chemical use publications. Respondents overwhelmingly indicated that the chemical use reports prepared from the survey data are helpful. Respondents found the data useful for determining trends in chemical use, rates of application, and methods of application.
Respondents consider the data to be reliable and useful for making market and policy decisions.
Some suggested expanding coverage to additional crops and States, and publishing statistics for infrequently used products. Data from the surveys are also used to support policy research. Together, this information will enable us to examine the effects on water quality of on-farm agricultural chemical use and production practices. USGS is helping us establish the land use-water quality linkages. These study regions were selected on the basis of the presence of agricultural cropland, significance of agrichemical use, the presence of soils that leach, and a significant water quality demand.