Survey and Control of the Boll Weevil in West Texas with Traps Baited with Males123

Abstract

Traps baited with live male Anthonomus gandis Boheman were effective for surveying populations of overwintered and migrating boll weevils, but in midseason, competition from males in fruiting cotton and decreased movement of weevils from field to field reduced the effectiveness. The larger catches observed in all areas from about Aug. 20 indicated that dispersal of weevils occurred at this time. Traps placed in and around a field of cotton in an area heavily infested with boll weevils captured > 4000 overwintered boll weevils per cotton acre but failed to reduce populations because the weevils in the traps could not compete with the large number of native weevils in the cotton. Traps placed in and around a field of cotton in an area with a small population of weevils (inside the Texas High Plains reproduction-diapause control zone) captured enough overwintered boll weevils to suppress the population until dispersal began. Thus, the pheromone of the male boll weevil is a potential tool for future survey, control, and eradication programs, but the population of overwintered weevils must be reduced throughout a large area before the traps can prevent buildup of populations to damaging levels or accomplish eradication.