Stink Bug Season in Nassau County
Every fall, brown marmorated stink bugs invade Nassau County homes by the hundreds. Learn why they come in, how to keep them out, and what to do once they're inside.
The brown marmorated stink bug (*Halyomorpha halys*) has become one of the defining seasonal pest events across Nassau County. Every fall — typically from late September through November — these shield-shaped, mottled-brown insects begin congregating on the warm, sun-facing exterior walls of homes and office buildings, searching for gaps to overwinter inside. What follows can be weeks of finding stink bugs on curtains, lamp shades, window sills, and anywhere else they wander as temperatures fluctuate inside the home.
Why Nassau County Has a Stink Bug Problem
The brown marmorated stink bug is an invasive species from Asia, first detected in the United States in Allentown, Pennsylvania in the late 1990s. It has since spread to all 50 states. In Nassau County, populations have grown steadily over the past decade, with reports increasing particularly in communities with mature tree cover and suburban gardens — areas like Syosset, Woodbury, Jericho, and the North Shore corridor.
Stink bugs are agricultural and ornamental pests during the growing season, feeding on fruit trees, vegetable gardens, and landscape ornamentals. Nassau County's mix of residential properties with fruit-bearing trees (apple, pear, peach), ornamental berry plants, and vegetable gardens provides an ideal summer habitat. As days shorten and temperatures drop in fall, these populations aggregate and begin seeking overwintering sites — including the interior voids of homes.
How They Enter Nassau County Homes
Stink bugs are remarkably good at finding small openings. Their flat body profile allows them to fit through gaps that seem impossibly small. Common entry points in Nassau County homes include:
- Gaps around window and door frames, particularly older single-hung and double-hung windows where the frame has contracted or settled
- Torn or damaged window and door screens
- Utility penetrations — gaps around cable TV lines, phone lines, and air conditioning lines entering through walls
- Attic vents and soffit vents without properly maintained screening
- Cracks in exterior siding, particularly where wood trim meets siding and at corner boards
- Chimneys without caps
Once inside wall voids and attic spaces, stink bugs can congregate in the hundreds or even thousands. A warm winter day will bring them out of dormancy and into living areas — appearing on windows and walls as if from nowhere.
The Smell Problem
When disturbed, threatened, or crushed, stink bugs release a defensive chemical from glands in their thorax. The odor — described variously as cilantro, skunk, or chemical-burning — is persistent and noticeable. Vacuuming stink bugs in a standard vacuum disperses the odor through the exhaust. Crushing them makes the smell worse. This makes removal in homes with active indoor populations genuinely unpleasant without the right approach.
Effective Control and Exclusion
For stink bugs, exclusion — sealing entry points before the fall congregation begins — is significantly more effective than any treatment applied after they're inside.
A fall exclusion inspection should cover all window and door frames, utility penetrations, vent screens, soffit conditions, and any cracks in exterior cladding. Caulking should be applied to all gaps around frames and penetrations. Window and door screens should be repaired or replaced. Attic and soffit vents should be screened with appropriate mesh.
For homes with existing interior populations, a professional exterior perimeter treatment applied in late September or early October — targeting the aggregate zones on sunny exterior walls — significantly reduces the number that make it inside. The treatment residual deters new arrivals and kills those that contact treated surfaces. Treated surfaces are clear to re-enter for family members and pets once dry — typically within 30–60 minutes.
Interior stink bugs are best removed by hand into a bucket of soapy water or with a vacuum fitted with a stocking trap over the exhaust to contain the odor.
Planning Ahead
The key to stink bug season in Nassau County is acting before the congregation begins — ideally by the second week of September. Once large numbers have entered wall voids, the winter emergence problem is difficult to fully resolve until spring.
Liberty Pest Pros provides fall exclusion services and exterior perimeter treatments for stink bug management throughout Nassau County. Call (516) 763-4600 for a fall assessment.