In replicated field tests, several Bacillus thuringiensis Berliner (BT) formulations were compared with standard insecticide formulations for seasonal control of Heliothis spp. larvae on cotton. Dipel^® (HD-1 strain) provided better control than previous strains of BT, and Dipel plus the boll weevil bait improved its performance. The favorable performance of Dipel was dependent on population pressures, weather conditions, methods of application, and the composition of the insecticides in the treated control.