When the weather cools, brown marmorated stink bugs gather by the hundreds on warm New Jersey walls and push inside to overwinter. Here is why, and why sealing beats spraying.
A pest New Jersey knows too well
The brown marmorated stink bug is an invasive insect that has thrived across New Jersey, and Bergen County gets the fall invasion as reliably as anywhere. As the first cool nights arrive, the shield-shaped bugs gather by the hundreds on warm, sunny south- and west-facing walls, soaking up heat and looking for a way inside to spend the winter.
They are not after your food and they do not bite or breed indoors. They are simply looking for a sheltered place to overwinter, and the warm wall of your house is exactly what they want.
How they get in
Stink bugs exploit the same gaps that let other pests in: openings around windows and doors, gaps in the siding, utility and pipe penetrations, vents, and the soffit and roofline. Once through, they settle into wall voids and attics and go dormant.
The frustrating part comes on warm winter days and again in spring, when the dormant bugs wake up, get confused, and turn up inside the living space at windows and light fixtures. By then they are coming out of the walls, where sprays cannot reach them.
Why spraying inside disappoints
Once stink bugs are inside a wall void, insecticide reaches very few of them, and crushing or vacuuming them releases the odor they are named for. Killing them inside the wall can also draw other pests. Reacting after they are indoors is mostly a losing game.
The approach that works is exclusion before the fall push: sealing the reachable gaps around windows, vents, soffits, utility lines, and siding so the bugs cannot get in, combined with a well-timed exterior treatment on the walls while they are gathering outside in late summer and early fall.
What you can do now
Seal what you can reach: caulk gaps around window and door frames, repair torn screens, and close obvious openings at utility penetrations. Keep the exterior treatment timed to late summer, before the bugs congregate, for the best effect.
If stink bugs cluster on your walls every fall, or you are already finding them indoors on warm days, a local pest control provider can seal the entry points and time the exterior treatment. Call and describe what you are seeing.
Call and describe what you are seeing. We will match you with an Englewood-area provider.