Hello,

The brown marmorated stink bug 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 of the year. Once inside, they congregate almost anywhere. These pests 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 wall 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.  Stink bug traps are also effective in removing these unwanted guests. For a good DIY trap see https://vtnews.vt.edu/articles/2014/05/050714-cals-stinkbugtrap.html. 

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 outsides of homes will, no doubt, involve spraying above one’s head.  Be sure to wear protective clothing such as a wide-brimmed hat and raincoat.  Eye goggles are a must.