Whitening of the damaged druplet results from plant bug feeding on mature fruit. Injured fruit tend to crumble easily and are generally unmarketable. Other plant bug species and stink bugs can cause similar damage. They are coppery brown with a yellow-tipped triangular area on their backs. The immature stages, or nymphs, are smaller and bright green.
Nymphs resemble aphids but are much more active than aphids.
In the spring, they are attracted to flower buds and shoot tips of many plants, including apple, peach, and strawberry. Several generations of this insect develop each year, and adults and nymphs are present on many different plants from April or May until a heavy frost in the fall. Adults of early and midsummer generations move onto blossoms and fruits of brambles as fruit begins to form. Controlling weeds in and around brambles helps to reduce populations of the tarnished plant bug. However, weeds and nearby forage crops such as alfalfa should not be mowed when brambles are flowering and setting fruit, because mowing encourages the movement of tarnished plant bugs from these plants to blackberries and raspberries.