Green Stink Bug
Acrosternum hilare Say
Appearance and Life History
The green stink bug feeds on many plants, including native and ornamental trees, shrubs, vines, weeds, and soybean. The preferred hosts are generally wild plants, but as these plants mature these bugs move to soybean.
Green stink bug is a flattened, shield-shaped bug, named for the offensive odor it produces. The adult is bright green and about 2/3 inch (17 mm) long. It is easily distinguished by the triangular-shaped plate that partially covers its wings.
The nymphs hatch from clusters of barrel-shaped eggs. They closely resemble the adults throughout their several nymphal stages. However, the nymphs are wingless, black and red in color and lack the triangular plate.
Green stink bug may appear in soybean fields from mid-July through harvest time. Often they are most numerous in the border rows next to weedy or wooded areas.
Both green stink bug adults and nymphs feed by means of their piercing-sucking mouthparts. They cause injury to soybean by puncturing pods and sucking fluid from the developing beans. This feeding can cause pods to form hardened, knotty spots or to drop from plants. Seeds that do develop despite stink bug pod feeding may be smaller, shriveled, and/or discolored. This damage may lower bean quality, and stunted seedlings may develop from damaged seeds.
If stink bugs are found in a field after the pods have begun to form, take 20 sweeps with a sweep net in each of 5 field areas. Determine the average number of bugs per sweep. Also, observe the border areas to determine if stink bugs are numerous and threatening the crop.
Soybean Insect Control Recommendations: E-series 77-W (PDF)
Commercial Soybean - Control may be necessary if there are 40 stink bugs per 100 sweeps (0.4 bugs/sweep) and pods are still green.
Seed Soybean - Control may be necessary if there are 20 stink bugs per 100 sweeps (0.2 bugs/sweep) and pods are still green.
If control is necessary, contact your state Cooperative Extension Service or click here for control materials and rates.