Of 7 tests conducted in Louisiana and Texas, 2 showed significant reductions in Heliothis spp. larvae following applications of Bacillus thuringiensis var. kurstaki (0.5 lbs of Dipel/ac or 3.63 Billion International Units/AC). Worm damage to squares was significantly reduced in 2 tests, but significantly higher than untreated check plots in 2 other tests. Yields were not significantly improved by Dipel applications. Some beneficial arthropod species were significantly reduced in the Dipel plots but no species was reduced in more than 1 of the 7 tests.