Granulated Insecticides for Control of the European Corn Borer in Southwestern Ontario1

Abstract

In 1956, sweet corn plots treated with hand applicators three times at weekly intervals with granulated endrin at 0.5 lb. of toxicant per acre or with granulated heptachlor at 1.5 lb. for control of the European corn borer (Pyrausta nubilalis (Hbn.)) yielded over 95% marketable ears. Plots treated with DDT emulsion, granulated DDT, and granulated toxaphene at 1.5 lb. of toxicant per acre yielded 80%, 73%, and 62% marketable ears, respectively. Only 2% of the ears in the untreated check plots were marketable. In 1957, a commercial applicator being used. granulated heptachlor at 1 lb. of toxicant per acre, granulated endrin at 0.3 lb., and granulated Dipterex at 1.5 lb. reduced the number of larvae by over 90%; a DDT emulsion spray at 1.5 lb. and granulated DDT at lb., 87% and 84%, respectively. The percentage of marketable ears for the treatments were: heptachlor, endrin, and Dipterex, over 90%; DDT, over 85%; untreated check, 14%.