egy since these materials first appeared in the late 1940's (NAS 1975, Pimentel 1976). Insecticides, along with the other agricultural chemicals, new plant varieties, and mechanization, have substantially increased crop production (NAS 1975). USDA officials maintain that without them 70% of crops produced in the United States could not be successfully grown, and those which could would suffer additional losses with an attendant rise in food prices of 50 to 70% (Shaw 1971, Walker 1969). Chemical insecticides have also