A new bioinsecticide, GemStar LC , is based on an insect-specific baculovirus which causes a lethal infection in bollworm and tobacco budworm larvae. It is produced by Thermo Trilogy Corporation (which purchased this and other biopesticide product lines from biosys, Inc. in January 1997), and became commercially available in 1996. It provides a safe and effective means of controlling young larvae without disrupting natural control of cotton pests by natural enemies. Recommendations are given for using GemStar LC in management of cotton pests.