SUMMARY
An economic evaluation was conducted on near isolines of cotton cultivars that did or did not contain Bollgard® technology for their usefulness in the defense of cotton bollworms Helicoverpa (=Heliothis) zea (Boddie), tobacco budworms Heliothis virescens (F.) and other insect pests at a northern and southern location of the Texas High Plains. The most intense insect pressure came from beet armyworms Spodoptera exigua (Hubner), an insect not targeted for Bollgard® control, in the southern location. Conventional insecticide applications saved an average 178 lb/ac of lint cotton, but were not economically feasible because of the cost and number of insecticide applications. The northern location did not result in any insect pest surpassing the economic threshold, especially those targeted for control with Bollgard®. The benefits of preventing secondary pests outbreaks from cotton aphids and other pests did not present itself in the two years and two locations of this study.