A Farmer’s Choice of Weed Control Method and the Impacts of Policy and Risk

The importance of risk in a fanner's decision to use herbicides should not be forgotten. This paper presents a theoretical model of the weed control decision and develops a MOTAD programming model. The model uses herbicides at levels of risk aversion found in previous empirical studies. Thisresult was not changed by equal (or even higher) ASCS yields for not using herbicides, a tax on herbicides, or the elimination of deficiencypayments. The variabilityof returns was more important in influencing a farmer to choose herbicides than the higher expected returns in a nonherbicide system. Most U.S. farmers have adopted chemical over mechanical and cultural methods of weed control. In the four years from 1986-1989, farmers treated 96 percent of the corn and soybean acreage in the U.S. with a herbicide (U.S. Department of Agriculture). Farmers saw chemical weed control as both yield-increasing and risk-reducing. Timeliness and convenience were also mentioned as reasons for chemical weed control; however, Bender (1990b) refutes the validityof these arguments. Federal policies have been cited as another reason for the use of herbicides (National Research Council). According to the 1987 agricultural census, 81 percent of all cropland in the U.S. treated with a chemical for weed control was on a farm participating in Federal programs (Padgitt). Instead of being the primary method as it was before herbicides were available, mechanical and cultural weed control has become complementary to control by herbicides. However, in recent years, society has become concerned about actual and potential environmental damage, degradation of food quality and safety, and health concerns of th