Named for its smelly-foot-like odor when crushed, the brown marmorated stink bug (Halyomorpha halys) is relatively new to the U.S. This stinky bug has become a big problem in homes, especially, it seems, in North Carolina. The bug is believed to have been brought into the eastern U.S. from China, Japan, Korea, and/or Taiwan in the later 1990s.
Stink bugs are becoming more than just a nuisance pest in agricultural areas of the eastern U.S. Like squash bugs and boxelder bugs, they are not known to breed indoors, cause interior damage, or harm humans. But stink bugs can be a real nuisance and cause alarm when they appear on draperies, blinds, lights, or even buzzing around one's head in the home. The bugs enter the home's structure through cracks and gaps, then come into our living areas when they feel the warmth of the interior.
Use this guide to help identify the stink bug:
- Color: Although the brown marmorated is the most common stink bug in the U.S., a green variety of stink bug can also be found in the Southeastern and South Central states.
- Shape: Stink bugs are shaped like shields and are 1/2 to 3/4 inches long. Young stink bugs are similarly shaped, but are more rounded and may be black or light green.
- Behavior: Similar to boxelder bugs, stink bugs will congregate on exterior building walls in the fall, seeking hidden areas in which to overwinter. They can also be a nuisance in the spring as they move further into the home and during summer when they feed on vegetation and crops.
In the home, stink bugs are little more than a nuisance pest to people because they do not sting or bite and they don't cause structural damage to homes or buildings. They can cause significant damage to trees, shrubs, and vines, as well as tree fruits, blackberries, corn, beans, tomatoes, peppers, soybeans, and other crops. Although they prefer wild plants, stink bugs will eat more than 50 different vegetation varieties.
The stink bug's needle-like mouthpart pierces seeds to feed on their nutrients. The amount of damage to the plant is dependent on the developmental stage at which the bug fed. The stink bug can also transmit yeast-spot disease to plants while it feeds.
The stink bug's odor repels many potential predators, but a number of common bird species prey on the insect for food. With so few natural predators, the stink bug can become quite obnoxious to humans.
Unfortunately, according to Rutgers University Extension Service, "there are no viable strategies for control of the Brown Marmorated Stink Bug. The use of insecticides has a very short-lived effect and there is evidence of resistance development. Even where insecticide is effective, repopulation occurs through migration from non-treated areas."
For this reason, the best defense against the stink bug is a good offense:
- Home or Building Exterior: Insecticidal spraying by a licensed professional can provide some control of bugs on exterior walls. Because the sun and weather can break down the insecticide, it will only be effective for a few days to a week, depending on the weather. The best defense is inspecting your home's exterior to find and seal all cracks and openings which will prevent the bugs from entering. Caulk around incoming pipes, utility wires, and cables, repair any broken window and door screens and ensure door and window seals are intact.
- Interior: If the bugs do get inside, entomologists highly recommend against the use of insecticides. It is best to follow insecticide-free practices. Vacuum and dispose of any stink bugs found inside the home (or flush them down the toilet). Because the dead bugs can attract other predacious insects like carpet beetles, any insects killed with insecticide would still need to be vacuumed or swept. The bugs do not sting or breed indoors and contrary to urban myth, dead stink bugs do not attract other stink bugs. Live stink bugs will emit odors to attract other stink bugs.