Issue 18, October 22, 2012

New Uninvited Fall House Guests: Brown Marmorated Stink Bugs

Like many invasive species, the brown marmorated stink bug (BMSB) has a long list of host plants, including many woody ornamental trees as well as several agricultural crops including fruit trees, grapes, tomatoes, corn, soybeans and others. Also, like many other invasive insects, it is easily moved from location to location by humans (hitchhiking on vehicles, movement of shipping materials, and movement of plants). In the eastern part of the U.S., where very large populations of this insect occur, economic damage has been seen in several crops. They are also causing lots of problems for homeowners as well.

Brown marmorated stink bugs on the side of a house.

It's during this time of year that we see insects hanging out on the sides of houses, garages, and window sills on sunny days, checking out places to spend the winter. While boxelder bugs and multicolored Asian lady beetles first come to mind, in several areas of the state, BMSB is starting to make its presence known as well. Typically, the adults will begin to move to overwintering locations in September, with peak movement in late September and October. Homeowners may start to see BMSB begin gathering on homes, barns, and garages during this time. In the spring, adults will begin to emerge from their overwinter locations as temperatures begin to warm.

BMSB has been making headlines in Illinois for a couple of years. After the first confirmation of this invasive insect was reported in the fall of 2010 (Cook County), additional reports continued in 2011 (Kane, McLean, and Champaign counties). Recently, we have confirmed BMSB in Jacksonville (Morgan County) and the first report has also come out of the Quad Cities area (Scott County, Iowa).

Currently, the known distribution of this insect in Illinois is limited. Homeowners are our primary source of information during the fall and spring. We are very interested in where these insects may be and continue to try to determine where they are in Illinois. If you believe you have BMSB, we would be very interested in looking at it. To positively confirm any insect as BMSB, we need to look at an actual specimen. Suspect stink bugs may be sent to Kelly Estes, 1816 S. Oak St., Champaign, IL 61820. Please put stink bugs in a crush-proof container (pill bottle, check box, etc). You can also send a photo to for preliminary screening if you wish.

Brown marmorated stink bug.

Spined soldier bug.

Common brown stink bug.

Western conifer seed bug.

Squash bug.

Adult BMSB have the typical "shield" shaped body of all stink bugs. In reference to their name, they have a marmorated or mottled brown color. Their antennae have distinct white bands; on the edge of their abdomen they have alternating black and white bands. The underside of the abdomen is white and the legs may also have faint white banding. There are several insects found in Illinois that are very similar in appearance, including the squash bug, common brown stink bug, western conifer seed bug, and spined soldier bug. (Kelly Estes)

Kelly Estes

Return to table of contents