The Ultimate Guide to Stink Bug Control in Kentucky
Pest Expert Matthew S. Hess
10/17/2025
Many Kentuckians have been introduced to stink bugs (Halyomorpha halys) in the last decade through home infestations. These pests were common in other states and gradually made their way into the Commonwealth, where they have found plenty of homes to invade. Since they have become a common pest in Kentucky, their numbers have continued to increase, and their infestations appear to grow larger each year.
While these insects pose no serious threats, their infestations can be alarming, inconvenient, and persistent. This comprehensive guide will help you understand and manage these persistent insects effectively, allowing you to reclaim your home and regain peace once again.
History and Introduction to Kentucky
The Brown Marmorated Stink Bug (BMSB) was first detected in Kentucky in 2010 and has since spread throughout the state. Originally from East Asia, these insects have become established pests in both urban and agricultural settings, causing homeowners and farmers alike to be wary of their presence.
Biology and Identification
- Size: Adults measure 1/2 to 3/4 inch long
- Color: Mottled brown with alternating dark and light bands on antennae
- Shape: Shield-shaped body
- Distinctive Features: White bands on legs and alternating dark/light pattern around abdomen
Life Cycle
Stink bugs undergo incomplete metamorphosis with three life stages:
Egg Stage
Eggs are laid from May through August, in clusters of 20-30, on the underside of leaves and similar areas. Depending on various environmental factors, up to two generations may be produced per year. Within 4-5 days, eggs will hatch into the nymph stage.
Nymph Stage
Nymphs hatch from the eggs and begin their five growth stages, which are accomplished through the ecdysis (molting) process. This process involves the nymph shedding the hard, outer layer of its exoskeleton, making room for growth from 2.4mm to 12mm in size.
In the early stages, the nymph resembles a tick, characterized by its red and orange coloration. As the stages advance, they begin to resemble their adult counterparts, and their true marbled brown, black, and white colors become more prominent with each molt. Each of the five nymph stages lasts about a week.
Adult Stage
At around ½ to 5/8 of an inch long and shaped like a shield, the Brown Marmorated Stink Bug has finally molted into an adult and taken on its unique mottled (or marbled) brown colorations. These colorations include light and dark bands on the antenna and alternating light and dark bands along the edge of the abdomen. Most adults will live 6-8 months and be active from August through October, and then shortly again in early spring (March and April) as they emerge to reproduce. During late summer and early fall activity, they will begin to seek shelter for the winter. This is when homeowners will start to see their numbers increase indoors.
The adult Brown Marmorated Stink Bug (BMSB) has a distinct body shape and patterned exoskeleton that clearly identifies this species.
Behavior Patterns
Adult activity typically occurs in large numbers and is a primary concern for homeowners, often being most prominent on warm days. Once the BMSBs have infested a home (typically through gaps and cracks around the exterior), they will prepare to enter a hibernation-like state for the winter. During warm days, especially when the sun is shining, adults may become active for a short time. During these periods, they will be attracted to light (usually around windows when inside), or some may even briefly emerge outside along their original entry points.
Control Methods
Control of the BMSB is most effectively achieved without the use of pesticides. In fact, they can be controlled entirely from invading most buildings if the proper steps are taken.
Prevention and Exclusion
Seal points of entry, such as gaps, cracks, and holes around a building’s exterior, as these can easily allow the BMSB to enter. Special attention can be paid to vulnerable areas like:
- Windows
- Doors
- Door frames
- Ridge Cap/vent
- Gable vents
- Soffit
- Chimneys
- Electric and plumbing penetrations
- Metal roofing trim (and closures)
Each of these areas can allow BMSB entry when they are either not properly installed, not properly maintained, or otherwise become old or damaged. Simple fixes like repairing torn window screens, sealing gaps around doors and windows, sealing gaps and cracks around chimneys, trims, soffits, vents, and other similar areas, and installing door sweeps, gaskets, and other failing structural components, will not only stop BMSB from entering, but most other pests as well.
Gaps and cracks like this one (between the chimney and soffit) allow easy entry for stink bugs and many other pests.
Habitat modification
Manage landscaping by trimming vegetation away from the home or other buildings, removing leaf litter and grass clippings, and keeping mulch at least 12 inches away from the foundation. Keeping the perimeter of the house dry and clean is crucial for controlling a wide range of pests.
Physical Control
If BMSBs have already entered your home for the winter, it’s too late to stop them this season. To help reduce their numbers, however, you can use the following tools:
- Sticky traps
- Vacuum
- Light traps
- Mechanical exclusion devices
By placing sticky traps in areas of high activity, you can reduce BMSB numbers as they emerge on those warm, sunny days. When high numbers are present and active, a thorough vacuuming can have a significant impact on their numbers as well. Be sure to empty the contents into a sealable bag and dispose of it in an outdoor garbage receptacle.
If large numbers of BMSBs are present inside the attic, a good light trap with a sticky board can make tremendous progress, as long as it is regularly monitored. Mount the light according to the manufacturer’s instructions, ensuring all safety protocols are followed. Plug it in and observe the progress.
Chemical Control
When prevention or mechanical control for an existing infestation is ineffective, or exclusion measures are too complicated or costly to implement, chemical control may be necessary or can be implemented in conjunction with other control options. In either case, chemical control measures should be targeted at areas of entry or current activity. For instance, perimeter eve treatments can reduce the number of incoming BMSBs that would enter a building.
Tips for Homeowners
As fall approaches, it is essential to monitor the exterior of your home for BMSBs. Inspect areas of concern, such as cracks and crevices in the soffit, vents, plumbing penetrations, windows, doors, and similar areas. When areas of congregation are found, take action to prevent their entry as soon as possible. In this way, the problem is prevented from extending beyond this point, thereby suppressing population growth and future infestation. Additionally, regular home maintenance to repair any deficiencies is essential.
When to Call the Professionals at Four Seasons Pest Solutions
When you find that the problem is too complex, too costly, or just something you don’t want to deal with on your own, calling in reinforcements is your best bet. Here at Four Seasons, we offer thorough inspections, customized treatment plans, prevention and exclusion programs, and follow-up monitoring, along with warranties. In fact, we’re so good at what we do that all your neighbors will tell you, “It’s good to have Four Seasons on your side!”
And remember, it’s okay to live among pests… but you don’t have to live with them!
Four Seasons Pest Solutions
Four Seasons Pest Solutions