As the temperature drops, many insects will search for shelter for the winter months – many times in OUR homes! This year, people may notice a new insect coming indoors.
This new insect is the brown marmorated stink bug. This insect has arrived in several Kentucky counties, and county agents are seeing them brought into the Extension Offices by homeowners for identification. University of Kentucky entomologists are receiving calls from the agents concerning this new stink bug’s appearance, said Ric Bessin, Extension entomologist with the UK College of Agriculture.
The species is native to Asia and came into the United States in the mid-1990s, possibly stowing away in a shipping container. Control of this particular insect can be difficult.
The brown marmorated stink bug has the characteristic shield-shaped stink bug body. The adults (with wings) are approximately 5/8-inch long with a mottled brown-grey body. The next to last (fourth) segment of each antenna has a white band. Edges of the abdominal segments that extend laterally from under the wings are alternatively banded with black and white. The underside of the body is white to light gray with grey or black markings, and the legs are brown with faint white bands.
There are other types of stink bugs and other insects that may fit this description. Bringing the insect to the Extension Office for positive ID is the best way to know what you have.
The first report of this stink bug in Kentucky was in 2010, but it is now confirmed in 13 counties, mostly in the northeastern part of the state and the Louisville area. Six additional counties have reported complaints of stink bugs in homes this fall. Franklin County Extension Office has not yet confirmed that it is here, but we feel certain it is and just not positively identified at this time.
Once the stink bug gets in homes, it releases an odor that smells much like cilantro as a defensive mechanism. The odor will occur most often when the insect is disturbed or crushed.
Along the East Coast, where this stink bug is more established, it has been known to invade homes by the tens of thousands. In Kentucky we are experiencing much smaller invasions, but for some people, just one insect is enough! These insects will not harm people, pets, furniture, food, or other house and home items. The insect is just a nuisance.
When found outside during the warmer months, it feeds on a large number of high-value crops and ornamental plants in its immature and adult life stages. The bug feeds on the sap of a wide range of plants including fruits, vegetables, ornamentals, and some field crops.
In other States, where the population of the insect is greater, significant losses have been reported from apple and peach orchards, blackberry, field and sweet corn, tomatoes, lima beans, and green peppers.
The best thing homeowners can do to prevent stink bug problems is to pest proof their residences, Bessin said. This includes sealing off openings into the structure such as where wires and pipes enter the building from the outside and any cracks or tears in window or door screens.
Homeowners may also want to spray an insecticide around the exterior perimeter of their home. Homeowner products containing the active ingredients deltamethrin, cyfluthrin, lambda-cyhalothrin, cypermethrin, or permethrin are options. They should be applied in now as the bugs begin to congregate.
These insecticides are broken down by sunlight so the residual effect will decrease and may not kill the insects much beyond several days or a week. When applying pesticides, read and follow all label directions.
If stink bugs are found in a residence, homeowners should vacuum them rather than sweep or crush them. Sweeping or crushing may cause them to emit the odor or leave a stain, Bessin said.
For positive identification of the insect, you can email a photo to the Franklin County Extension Office. Or capture a few of the insects in a small plastic bag or container (do not add alcohol or other liquid) and bring that into the Extension Office.
Those wanting more information on the brown marmorated stink bug can refer to UK Entomology’s ENTFACT 641, which can be found online at http://pest.ca.uky.edu/EXT/BMSB/welcome.html.
Or you may contact the Franklin County Cooperative Extension Service at 695-9035 or email DL_CES_Franklin@email.uky.edu.