Mosquito Season in Westchester County
Mosquitoes become active when temperatures consistently exceed 50°F — in Scarsdale, that means mid-April through October. Peak biting pressure runs July through September, overlapping directly with outdoor entertaining season.
Westchester County is a recognized surveillance zone for West Nile Virus (WNV), carried by the Culex pipiens mosquito — the most common species breeding around Scarsdale homes. Beyond nuisance, mosquito exposure carries real health risk for families and pets alike.
Disease Risks in Scarsdale
- West Nile Virus: Monitored annually by the Westchester County Health Department; transmitted via Culex mosquitoes breeding in stagnant water
- Eastern Equine Encephalitis (EEE): Rare but serious neurological infection found in wooded wetland corridors near Westchester
- Dog Heartworm: Dirofilaria immitis transmitted to dogs and cats through a single mosquito bite
Our Mosquito Control Program
Licensed professionals in our network deliver a three-part system tailored to Scarsdale properties.
Barrier Spray Treatments
A residual barrier spray is applied to resting zones mosquitoes return to throughout the day:
- Perimeter shrubs, hedgerows, and tree lines
- Ornamental beds and groundcover
- Shaded lawn perimeters and fence lines
- Undersides of decks and outdoor structures
Treatments use EPA-registered pyrethrins or synthetic pyrethroids — low mammalian toxicity, rapid environmental breakdown, 21–28 days of residual protection per application.
Larvicide Applications
Where standing water cannot be eliminated, technicians apply Bacillus thuringiensis israelensis (Bti) — a soil bacterium that kills mosquito larvae without harming other wildlife. Targeted areas include decorative ponds, drainage swales, and low-lying areas that collect rainwater.
Source Reduction Consultation
Every visit includes a property audit identifying breeding sites unique to your yard. A single teaspoon of standing water supports a complete mosquito lifecycle in as few as 7–10 days.
Common Breeding Sites Around Scarsdale Homes
- Clogged gutters — the #1 breeding site around residential properties
- Birdbaths — change water at minimum twice per week
- Pool covers — depressions collect water after every rain event
- Tarps and yard equipment — even small depressions accumulate enough water
- French drain outlets — blockages create persistent standing pools
- Tree holes and stumps — natural cavities that retain rainwater
Frequently Asked Questions
When should I start mosquito treatment?
Begin in early May, before mosquito populations establish. Starting early prevents the first generation of larvae from maturing into biting adults — dramatically reducing season-long pressure on your property.
How long does a barrier treatment last?
Residual barrier sprays last 21–28 days per application. Heavy rain within 24 hours of treatment may reduce effectiveness and may warrant a follow-up visit.
Are mosquito treatments safe for children and pets?
Yes. EPA-registered products are safe once dry — typically 1–2 hours after application. Keep children and pets indoors during treatment and until all treated surfaces have fully dried.
Take Back Your Outdoor Space
Don't forfeit your patio, deck, or yard to mosquitoes. Our network of licensed specialists serves Scarsdale and all of Westchester County with proven seasonal programs.
Related Resources
For combined tick and mosquito protection, see our Tick & Mosquito Control page. For Westchester County mosquito surveillance data, visit the Westchester County Health Department.