Effectiveness of Fenoxycarb for Control of Red Imported Fire Ants (Hymenoptera: Formicidae)1

Abstract
The insect growth regulator fenoxycarb reduced colony size indices of laboratory colonies of red imported fire ants, Solenopsis invicta Buren, by 93-98% within 8 wk after treatment. Reductions were caused by lethality to developing immatures, inhibition of egg production by the queen, and a shift in caste differentiation from worker to sexual forms. No significant difference was noted in the response of colonies to 5 or 10mg (AI) per colony; the majority of colonies treated at either dosage died as a result of the treatment. In field tests, baits containing fenoxycarb eliminated ca. 60% of the colonies on treated plots and reduced total ant population indices by 67-99% within 12-13 wk after treatment at rates of 6.2-22.6 g (AI)/ha.