Home Invaders

Typically on the top of our home invader list in Illinois is Asian lady beetles. Asian lady beetles were released to help farmers with the soybean aphid but instead of overwintering in the cliffs of their native land, they like to invade our homes. If there is a crack or crevice leading its way to the inside of your home, then you may be vulnerable to this and other unwanted inhabitants.

"A new potential home invader may be looking for a spot to overwinter in Illinois homes this year and that is the Brown Marmorated Stink Bug (BMSB)," states University of Illinois Extension Horticulture Educator, Kelly Allsup. We have heard about invasions of homes in the Mid-Atlantic States in the past. They are a nuisance because they do what stink bugs do best – stink, but only when threatened.

This invasive insect was first identified in Pennsylvania in 1998 and was considered a stowaway from China. Brown Marmorated Stink Bugs have a large host range eating landscape, native and agriculturally important produce. According to a new study by a University of Maryland entomologist, adults have a strong preference for ripe fruit, leaving the nymphs to eat the plant material. This causes growers on the east coast, where the population has sky rocketed, to forfeit all efforts to be organic and pull out their arsenal of chemicals. Current research is being conducted on using trap crops, pheromone traps and biological control.

The BMSB has piercing mouthparts and is capable of damaging a multitude of crops from apples to pears to soybeans to landscape ornamentals. University of Illinois Extension Entomologist, Mike Gray, has said, "BMSB are capable of causing economic losses to soybean and corn producers." However, Kelly Estes, State Survey Coordinator at the Illinois Cooperative Agriculture Pest Survey Program, states, "The combination of lower populations of BMSB and highly managed crop systems in Illinois have kept detection and economic injury levels low."

"Most reports have come from urban areas in early spring and fall, generally from homeowners and master gardeners," says Kelly Estes. To control BMSB in the home, use a vacuum to suck up adults or take steps in early winter to caulk the house and prevent movement in from the outside. It is not recommended to use sprays in the home because insecticide residues are relatively ineffective in providing control.

BMSB has been identified in 41 states with Illinois being one of them. The state of Illinois is currently classified by USDA as being at low risk for the pest as large numbers have not been recorded. Horticulture Educator Kelly Allsup, Livingston-McLean-Woodford Unit encourages homeowners and gardeners to be on the lookout for this invasive pest as in the past few weeks she has found five BMSB on the screens of her windows at her Bloomington home.

BMSB has the shield-shape characteristic to stink bugs and it's as wide as it is long. The three most identifying characteristics are its black and white banding on the antennae, the alternating dark/light banding on the edge of the wings and the smooth shoulders. Theyare capable of aggregating in manmade structures and recent USDA studies shows they prefer large dead trees that are still standing in the forest-like oak or hickory on the East Coast. After overwintering in April, the adult lays 20-30 eggs with nymphs emerging shortly after. There can be multiple generations per year depending on seasonal temperatures.

Currently, the known distribution of this insect in Illinois is limited. Homeowners are our primary source of information and University of Illinois is interested in where these insects may be in Illinois. Twenty-one counties in Illinois have had positive confirmations of BMSB. This invasive insect is also believed to be inhabiting other counties, but this hasn't been confirmed yet.

If you would like to help, please visit The Brown Marmorated Stink Bug IPM Working Group and take the survey to let them know about the problems that you are experiencing with BMSB and what you are doing to tackle them. The survey can be found at https://www.surveymonkey.com/r/BMSBsurvey.

If you believe you have found a BMSB, please submit it to your local Extension office to get positive confirmation for your county.