A field study was conducted to determine the effectiveness of applications of Karate (l-cyhalothrin) to NuCotn 33B based on egg and larval treatment thresholds for bollworms (Helicoverpa zea [Boddie]), and to assess the impact of prior applications of acephate on populations of predaceous arthropods and the subsequent impact on bollworm and fall armyworm (Spodoptera frugiperda [J. E. Smith]) populations and damage. Main plots (acephate, no acephate) were subdivided into 5 thresholds: (1) 1 application of Karate at peak oviposition, (2) 1 application of Karate at peak oviposition followed by a 2nd application ca. 1 wk later, (3) 1 application of Karate when 3 large larvae (0.25-in. in length)/100 plants are present, (4) 1 application of Karate when 3 large larvae/100 plants are present followed by a 2nd application ca. 1 wk later, and (5) no applications of Karate.