Microencapsulated formulations (MEF) of malathion and Sumithion were compared to malathion ULV for efficiency in controlling adult Aedes sollicitans (Walker,) and the levels of malathion residues on vegetation and in soil were determined. Control of mosquitoes was greater and lasted longer in fields treated with the microencapsulated formulations. Within the 48 hr after application, malathion residues on vegetation in the MEF field. In soil the residue difference was 2.7. The correlation between depression of mosquito populations and the residual life of MEF warrants further research.
