Herbicides are applied to 92–97% of acreage planted in corn, cotton, soybeans, and citrus; 87% of potato acreage; three-fourths of vegetable acreage; and two-thirds of the acreage planted in apples and other fruit (ERS, 1997; see Table 2-1). Herbicide use is least extensive on winter wheat (56%). In contrast, insecticide use is much less widespread. Among row crops, insecticides are used most extensively in cotton, tobacco, and potatoes. About 30% of corn acreage is treated annually with insecticides, and insecticides are applied to 12% or less of wheat and soybean acreage. Insecticide use is quite prevalent, however, on fruit and vegetable crops. Nearly all apples, citrus, and potatoes and about 90% of other vegetable and other fruit crop acreage are treated with insecticides (ERS, 1997). Fungicide use is similarly highly prevalent on potatoes and fruit crops. Among row crops, only in cotton, tobacco and potato are fungicides used regularly; less than 10% of cotton acreage is typically treated with fungicides. The category “other pesticides ” includes defoliants, growth regulators, and soil fumigants, which are used widely on cotton and potatoes. Potatoes are particularly pesticide intensive—almost 90% of the acreage is treated, with fungicides and soil fumigants as the dominant types of treatment (ERS, 1997).

One measure of the intensity of pesticide use is reflected by calculat-