How to Manage Pests
UC Pest Management Guidelines
The adult false chinch bug is a small bug, about 0.12 inch or 3 mm long. It is gray to light brown in color and looks somewhat like a small lygus bug. The nymph is gray with a reddish brown abdomen.
False chinch bugs can occur in high numbers on weeds within or adjacent to pistachio orchards. The eggs are laid randomly on the soil or within soil cracks near weeds. The false chinch bug spends the winter primarily in the immature stage (nymph) on weeds. As weeds dry in spring or are destroyed, chinch bugs migrate to pistachio trees where they feed. Nymphs predominate during migration but adults may also be present. Important weeds that serve as hosts include wild mustard, wild radish, shepherd's-purse, and London rocket. The most serious infestations result from spring migrations; however, fall migrations can also occur. Movement occurs in early morning or evening.
False chinch bugs can be a serious problem on newly planted pistachio trees, especially when cardboard trunk guards are used, which shelter the bugs during the day. Their feeding can cause young trees to wilt and die. Feeding on older trees can cause leaves to drop.
On newly planted trees, if bugs are so numerous that wilting is evident, a treatment is warranted. Treat either in the evening or early morning when chinch bugs are active.
UC IPM Pest Management Guidelines: Pistachio