Boll Weevils (Coleoptera: Curculionidae): Emergence from Bolls During the Spring, and Trapping of Adults in Arizona

Abstract

Boll weevils, Anthonomus grandis Boheman, in Arizona continued to emerge until 23 May from infested bolls collected in December and placed above or on the soil surface under emergence cages during January or early February. Practically no emergence occurred when infested bolls were buried under 15 cm of soil under cages. Boll weevil captures in grandlure-baited traps were near zero during the summer (June–August), began to increase in the fall, reached maximum numbers in January and February, and began to decline in April of each year. The decline in numbers caught occurred at approximately the same time that the emergence from bolls was nearly complete. The relatively large catches of boll weevils during periods when no host was available suggests that emergence from bolls is occurring throughout this period and that large segments of the populations during the winter are not in a resting state, but are actively seeking host material or mates.