If you don't see the chinch bugs near the soil surface, push a bottomless can several inches into the ground in an area where the grass is turning yellow. Fill the can with water, wait several minutes, and any bugs will float to the surface. Chinch-bug damage also can resemble brown patch symptoms. Proper lawn care can go a long way in discouraging chinch bugs. Irrigate sunny areas that quickly become hot and dry.
Sufficient moisture can suppress chinch bugs.
Mow at proper heights. If chinch bug populations become a real threat to the lawn, apply an appropriate insecticide. But don't overdo it, because such treatments often wipe out beneficial insects and those organisms that decompose thatch. Sod webworms create patches of chewed blades. If they are present, you may notice webbing in affected areas in the early morning.