Jeffrey Hahn, Asst. UMN Extension Entomologist
This is a moderate-sized insect, measuring about ½ - 3/4 inch long. Like other stink bugs, it has a shield-like or triangular shaped body. The BMSB is brown with whitish mottling on its body. There are native stink bugs in Minnesota that are also brown and a similar size. The best way to distinguish between them is BMSB has alternating black and white markings on its abdomen. Also look for black antennae with white bands. The immature BMSB look similar but are smaller and lack wings.BMSB are pests because they feed on fruit, like apples and peaches and vegetables, such as corn, tomatoes, and soybeans. They feed on a wide variety of plants and are also found on many hardwood trees and shrubs and some herbaceous plants, although it is not clear how injurious they are to these plants. This year has seen an explosion in the numbers of this stink bug in many areas were they are already known to occur, causing loss in some crops.
Also watch out for BMSB in the fall as they can be pests by entering homes and other buildings as the weather starts to become cold, much like boxelder bugs and multicolored Asia lady beetles. In addition to their unwanted presence, they also give off a very disagreeable, pungent odor.
It is important to discover this insect as soon as possible when it first arrives in Minnesota so it can be controlled. If you believe you have seen a BMSB, report it to the Minnesota Dept. of Agriculture's 'Arrest the Pest' Hotline at 1-888-545-6684 (toll free). You can also e-mail them at Arrest.the.Pest@state.mn.us.