Chinch bug infestations frequently occur in turfgrass with thick thatch that is exposed to full sunlight during periods of hot, dry weather. Chinch bug damage is often less noticeable during the spring and early summer and more frequently appears from early July through late August when the insects are actively feeding. Chinch bug nymphs and adults cause significant feeding damage by removing plant fluids and by injecting a toxin that causes the grass to yellow, turn reddish brown, and eventually die. Chinch bug damaged areas often coalesce into large patches of dead, brown grass. The suggested economic threshold for chinch bug is 15 to 20 insects per square foot.
• An adult hairy chinch bug is about 1/6 inch long and has a gray-black body with fine hairs, white wings, and reddish legs.
• On the outside of each front wing is a small, black, triangular spot, and the wings of the adult fold flat over their backs.
• Young nymphs are about half the size of a pinhead and start out as being brick-red with a white band across the back; as the young mature, they turn gray and then black with wing pads developing as they grow.