Uninvited guests are rarely welcome in a home, especially when they are stink bugs. The brown marmorated stink bug, an insect that is relatively new to our area, has begun its annual search for winter shelter, which unfortunately includes local homes.
The brown marmorated stink bug, Halyomorpha halys, is a plant pest that was introduced into the United States from its native range in Japan, Korea, and China. The word marmorated refers to its marble-like coloration. Sometimes called the yellow-brown stinkbug or the East Asian stink bug, it was first reported in the United States in 2001 from Allentown, Pa. It has since spread to up and down the eastern seaboard and is moving west through Illinois.
The brown marmorated stink bug feeds on fruits and seed pods of a wide range of plants. The first crop damage in the state was found here in Elkhart County this summer in a field of soybeans near the Elkhart airport. There have also been reports of feeding on sweet corn and tomatoes. They are a challenging pest to control in crops and homes, because they are essentially resistant to insecticides.
In the wild, stink bugs normally overwinter in cracks and hollows of trees and shrubs. However, they have adapted to modern buildings, often crawling in through cracks and crevices in an effort to find a comfortable place to overwinter.
Because of their resistance to pesticides, the stink bugs can be extremely difficult to control. They can be mechanically excluded from homes and buildings by sealing cracks and other openings in the buildings. If bugs are entering the living areas of the home, the openings where the insects gain access first should be located, then sealed. Typical entry points include cracks and crevices around window and door trim, window-mounted air conditioners, exhaust fans, ceiling fixtures, baseboards and chimneys. Cracks or openings should be sealed with caulk to prevent entry by the stink bugs. Torn window screens should be repaired, and window-mounted air conditioners should be removed. Live and dead stink bugs can be removed from buildings with a vacuum cleaner or wet-dry vac, and the vacuum bag should be promptly removed and discarded.
Insecticides should not be used inside houses after the insects have gained access. Using an insecticide indoors is not recommended because this will not stop additional invasions, and exposure of humans and pets to pesticides should be avoided.
Also, you should be aware that a second “invasion” will occur later in the year. As the temperatures warm the outer walls of you home and office, the stink bugs will waken from their winter sleep and look for a way out. Unfortunately, half of the critters will stumble into the living space instead of finding their way outdoor.
Jeff Burbrink is an extension educator at Purdue Extension Elkhart County, 17746 County Road 34 Suite E, Goshen IN 46528-6898. Contact him at 574-533-0554, 574-533-0254 (fax) or firstname.lastname@example.org.