DDT and dieldrin residues on pasture following dusting and spraying

摘要

DDT was applied to short, dry pasture as an emulsion spray, dry mix/DDT superphosphate dust, or #x201C;wet#x201D; mix DDT/superphosphate dust, at the nominal rate of 2 lb pp'-DDTlac. Similar pasture was treated with dieldrin at the rate of 4 oz/ac as an emulsion spray or as a dieldrin/superphosphate dust. Residual insecticides were determined on the pasture at intervals up to 42 days.