Abstract
The insecticides aldrin, dieldrin, heptachlor, endrin, and diazinon were applied to Pullman clay loam soil at the rale of 1.6 lb/acre. The chlorinated hydrocarbons gave satisfactory control of wire worm (Conoderus sp.) and grub (Phyllophaga cribrosa (Leconte)), for 5 years after treatment. Soil-insect control with diazinon was not satisfactory. However, better control was obtained with crop rotation than with insecticides. Neither grain sorghum nor wheat yields were affected by the insecticides. The amounts of chlorinated hydrocarbon residue, detected at the end of 5 years, are also presented.