Field Evaluation of Perimeter Treatments for Pharaoh Ant (Hymenoptera: Formicidae) Control

Abstract

Four types of exterior perimeter treatments for the control of Pharaoh ants, Monomorium pharaonis (L.), in houses were compared. Treatment with a granular bait containing hydramethylnon, a delayed-action toxicant, resulted in a 95% reduction in foraging activity 1 and 4 weeks after treatment. Houses treated with either an insecticidal residual spray, insecticide granules, or a granular bait containing a contact insecticide, had an average increase of 22% in foraging activity. Foraging by Pharaoh ants on a delayed-action toxicant bait applied solely to the exterior periphery of houses controlled Pharaoh ant colonies located inside the structure. Exterior perimeter baiting for Pharaoh ants could reduce indoor insecticide applications.