Managing brown marmorated stink bugs in homes
How to prevent and get rid of brown marmorated stink bugs in your home or building.
The brown marmorated stink bug, Halyomorpha halys (Hempitera: Pentatomidae), is an invasive insect native to Japan and Asia. It was first discovered in Michigan in 2011. Since then, they have been slowly spreading throughout the state. In addition to causing damage to plants and fruit, brown marmorated stink bugs are a major nuisance because adult stink bugs often seek shelter inside houses and other buildings in the fall. Once inside, they congregate almost anywhere.
Brown marmorated stink bugs will not cause structural damage or reproduce in homes. They do not bite people or pets. Although they are not known to transmit disease or cause physical harm, the insect produces a pungent, malodorous chemical and when handling the bug, the odor is transferred readily.
The best long-term method of controlling these bugs in homes is to prevent their entry. In older homes with wooden clapboard siding, their entry can be reduced by caulking or sealing cracks and crevices on the exterior. No amount of caulk will keep the beetles out of homes with vinyl siding because vinyl siding and soffits are “hung” or loosely nailed to permit the vinyl panels to expand and contract with changing temperatures. Even with wood siding, complete sealing with caulk can be difficult, if not impossible, to accomplish in some homes. If sealing the exterior walls does not help, then caulking around outlet and switch boxes, ceiling fixtures, heat ducts and other openings in interior walls may at least keep the bug in the walls and out of the living space.
If sealing the exterior walls does not help, then caulking around outlet and switch boxes, ceiling fixtures, heat ducts and other openings in interior walls may at least keep the bug in the walls and out of the living space.
Sweeping or vacuuming can remove bugs already in homes. You may want to use an old, junker vacuum for this purpose because the bugs may live up to their name and “stink up” your vacuum.
Spraying the outside walls of homes, especially the south and west facing walls, in September and October can also help reduce the number of these insects entering homes. The spray should be applied when the first bugs are noticed congregating on outside walls, usually in September. Homeowners who choose to spray their homes can hire a professional pest control company to treat the building exterior. Do-it-yourselfers can use bifenthrin, sold as Ortho Max Home Defense. Before treating the whole house, spray a small test area to make sure the insecticide does not stain the siding or paint.
Be sure to read and follow all directions on the pesticide label. Spraying the outside of homes will, no doubt, involve spraying above your head. Be sure to wear protective clothing such as a wide-brimmed hat and raincoat. Eye goggles are a must.
If you have brown marmorated stink bugs in your home or building and do not live in the well-established areas (see map below), please report the sighting to the Midwest Invasive Species Information Network. For more information on how to report a sighting, see “Why and how to report sightings of brown marmorated stink bugs in your home or business” from Michigan State University Extension.