The potential effect of predators and parasites on bollworm, Heliothis zea (Boddie), and tobacco budworm, H. virescens J.), in cotton is often recognized in cotton insect control guides, but explicit instructions for using their numbers in decision-making are lacking except for one state, Texas. Consequently, emphasis is placed on conserving predators and parasites by delaying early season foliar applications of insecticides to the foliage; where aldicarb is used infurrow at planting, low rates (< 112 lb AI/acre) are recommended.

Numerous reports link decreased predator numbers (as a consequence of insecticide usage) with Heliothis population increase, increased damage due to Heliothis feeding, and reduced yield. Experimental and simulated data document high rates of Heliothis mortality in the field due to predation and parasitism. Predators and parasites can be more efficiently conserved by using insecticides that favor the metabolic processes best developed in them for detoxification. A conceptual decision-making model is presented that includes structures incorporated for Heliothis feeding, impact of natural enemies on Heliothis feeding and survival, cotton crop growth, mortality of Heliothis, parasites, and predators from insecticides, insecticide degradation, and the economics of pest control.