Spring Pest Prevention 2026: The Complete Westchester Homeowner Checklist

Why Spring Is the Right Time for All of These

Pest management has a timing problem: homeowners call when they see activity, which is weeks to months after the conditions driving that activity were set. A termite swarmer in May is evidence of a colony established years earlier. Carpenter ants in July indicate a satellite colony established in spring. Mice in November entered through a gap that was open all summer. In every case, the right intervention was earlier — before the pest established, not after.

Spring is the single best prevention window because it precedes the active phase of every significant Westchester pest category. Use this checklist to address each category before its season peaks.

Termites: Schedule Your Annual Inspection Now

Eastern subterranean termite swarm season in Westchester County runs from late March through June, with peak activity in April and May. If you have seen winged insects near your foundation, windowsills, or emerging from soil near the structure in the past four weeks, schedule a termite inspection this week — swarm evidence confirms a mature colony is established at or near your structure.

Even without visible swarmers, an annual termite inspection in spring is the most cost-effective form of protection available to Westchester homeowners. Termite damage is not covered by standard homeowners insurance and accumulates silently over months and years. The cost of annual inspection is a small fraction of the cost of structural repair after an undetected colony has been active for two or three seasons.

Spring action items: Schedule a professional termite inspection if you have not had one in the past 12 months. Inspect the foundation perimeter for mud tubes — the primary visible indicator of subterranean termite activity. Check the basement and crawlspace for any wood that has direct soil contact, and eliminate that contact where possible.

Carpenter Ants: Address Moisture and Dead Wood

Carpenter ant swarmers emerge in April and May; foraging workers are visible spring through fall. If you saw carpenter ants in your home last year, the parent colony is still within foraging range and the same conditions that produced last year's satellite colony are likely still present.

Spring action items: Inspect gutters and downspouts — clogged gutters overflow and wet the fascia and soffit, creating the moisture-damaged wood that carpenter ant satellite colonies target. Check window and door frame caulking for cracks or separation. Look for stumps, wood debris, and firewood stored near the foundation. Trim any tree branches that contact the roofline.

If you are seeing large black ants (¼ to ½ inch) inside consistently, this is not a DIY situation — it indicates a satellite colony already established in the structure. A professional carpenter ant removal program locates both the satellite colony inside and the parent colony outdoors, which is the only approach that produces lasting elimination rather than temporary suppression.

Mosquitoes: Start Treatment by Mid-May

The single most common mosquito control mistake is starting treatment too late. Mid-May is the correct start date for barrier spray in Westchester County in 2026 — the mild 2025–2026 winter has produced an earlier-than-average active season, with overwintered adult Culex mosquitoes already active in early May.

Spring action items: Clean gutters in April — clogged gutters holding organic debris are productive Culex breeding sites. Identify and eliminate any standing water sources on the property before the season begins: birdbaths (change water every 3–4 days), low-lying lawn areas, tarps, and decorative pots. Schedule the first barrier spray treatment for mid-May for continuous suppression from the season's start. For tick and mosquito combined protection on wooded properties, consider LymeShield as the more comprehensive solution.

Deer Ticks: April–June Is Peak Nymph Season

Deer tick nymphs — the stage responsible for the vast majority of Lyme disease transmission in Westchester County — are active from April through August, with peak density in May and June. Nymphs are the size of a poppy seed and nearly invisible, which is why the Westchester Lyme disease transmission rate is highest during this period rather than in late summer when adult ticks are more easily spotted.

Westchester County has one of the highest Lyme disease incidence rates in the United States. Properties with wooded edges, deer pressure, or adjacent to the county's reservoir and parkway corridors carry the highest nymph exposure risk.

Spring action items: Keep lawn mowed — nymphs are concentrated at the edge of tall grass and low vegetation, not in open maintained lawn. Create a wood chip or gravel barrier between wooded edges and lawn areas. Consider a professional tick treatment program — the LymeShield barrier spray applied from May through August targets the vegetation-to-lawn edge where nymph exposure is highest. For more detail on tick prevention, see our tick prevention guide for NY homeowners.

Rodents: Seal Entry Points While Mice Are Moving Out

House mice that overwintered inside your home are migrating back outdoors in April and May. This spring exit through known entry points is the annual window to find and seal those gaps before the fall re-entry pressure begins again in September.

Spring action items: Inspect the foundation perimeter for gaps at utility penetrations, cracks in mortar joints, and areas where different materials meet. Check all door sweeps — they should make complete contact with the threshold. Check garage door seals. Move firewood at least 20 feet from the structure. Eliminate dense groundcover against the foundation. For complete professional entry-point sealing with a written gap report, see our Home Shield Exclusion program.

Wildlife: Inspect Before Nesting Season Peaks

Squirrels, raccoons, and birds are all actively seeking nesting sites in spring. Attic voids, soffits, chimney caps, and gaps in the roofline are the primary targets. Wildlife entry problems are significantly easier and less expensive to resolve before a litter or nest is established — once young are present, removal becomes more complex and is subject to additional legal considerations depending on species and timing.

Spring action items: Inspect the roofline and soffits from the ground for damaged or missing sections. Check the chimney cap — chimney caps that have corroded or been displaced are a primary raccoon and bird entry point. Listen for scratching sounds from the attic, particularly in the early morning. Walk the perimeter of the structure and look for scratch marks, disturbed insulation visible through soffit vents, and any openings wider than 1.5 inches at the roofline. For active wildlife removal and exclusion, see our wildlife exclusion service.

General Pests: Schedule Your First Service Visit

Spring is when overwintering insects — stink bugs, box elder bugs, cluster flies — that sheltered in wall voids over winter begin emerging. It is also when pavement ants begin foraging along foundation edges and German cockroaches become more active with warming temperatures in kitchens and utility areas.

A spring perimeter treatment as part of a year-round Home Protection Plan addresses this emergence before it becomes an interior problem. The spring visit establishes the season's baseline treatment layer on which summer and fall visits build. For homeowners who do not currently have ongoing pest management, spring is the optimal enrollment window — you get the full benefit of the program from the season's start rather than catching up from an already-established population.

The Spring Prevention Priority Order

If you can only address a few items this spring, prioritize in this order based on consequence severity and time sensitivity:

1. Termite inspection — structural damage, not covered by insurance, accumulates silently. Highest long-term financial risk.
2. Tick treatment start — public health risk (Lyme disease) peaks in May–June. Time-sensitive.
3. Mosquito treatment start — nuisance and public health risk (West Nile). Start by mid-May for full-season coverage.
4. Rodent exclusion — spring exit window closes by June. Next opportunity is next spring.
5. Carpenter ant moisture assessment — property damage risk, highest in homes with prior moisture history.
6. Wildlife roofline inspection — time-sensitive before nesting season; easier and less expensive now than in June.