In 1998, we continued testing the potential for a group of non-crop plant species to act as a trap crop for the tarnished plant bug and a refuge for heliothines (tobacco budworm and cotton bollworm) susceptible to endotoxin proteins found in Bt cotton. Field studies were conducted, as in 1997, on commercial farms at several locations in the Mississippi Delta to determine the effectiveness of the trap crop/refuge system. Four alternate hosts (kenaf, pigweed, velvetleaf and sesame) were planted in a strip in the middle of three Bt cotton fields in 1998. As in 1997, velvetleaf appeared to be an excellent refuge host for heliothines. Pigweed, at least during part of the season, was highly preferred over cotton by plant bugs, and plant bug numbers remained low in cotton adjacent to the weed strip throughout June. However, populations of tarnished plant bugs exceeded treatment thresholds in all fields during July. Treatment of the weed strip with insecticide active against plant bugs significantly reduced their numbers in the adjacent cotton.