Total pesticide use, as well as the specific active ingredients used (for example, with novel target sites of action or improved toxicological profiles), has changed considerably over the past five decades.
Pesticide use on the 21 crops analyzed in this report rose rapidly from 196 million pounds of active ingredient (a.i.) in 1960 to 632 million pounds in 1981, largely because of the increased share of planted acres treated with herbicides to control weeds. In addition, the total planted acreage of corn, wheat and, in particular, soybeans increased from the early 1960s to early 1980s, which further increased herbicide use. Most acres planted with major crops (particularly corn and soybeans) were already being treated with herbicides by 1980, so total pesticide use has since trended slightly downward driven by other factors, to 516 million pounds in 2008 (the most recent year for which we have enough complete data).
The pesticide types applied by U.S. farmers for the 21 crops analyzed changed considerably from 1960 to 2008. Insecticides accounted for 58% of pounds applied in 1960, but only 6% in 2008. On the other hand, herbicides accounted for 18% of the pounds applied in 1960 but 76% by 2008.
Graph credits: ERS with USDA proprietary data; unless otherwise noted on graph.