Spotted Lanternfly inNew Haven County, CTSPOTTED LANTERNFLY GUIDE
New Haven County — Connecticut's second-largest county and home to Yale University — confirmed SLF in 2023 as populations advanced from Fairfield County along the Metro-North New Haven Line and I-95 coastal corridor. New Haven city sits at the convergence of I-91 and I-95, one of the most strategically significant freight interchanges in New England, creating a major ongoing SLF spread node. Yale University's extensive campus and botanical collections face direct SLF pressure, and the Quinnipiac River valley provides a natural SLF dispersal pathway inland from the Long Island Sound shoreline. Metro-North New Haven Line terminus at Union Station concentrates commuter and tourist traffic from the established Westchester and NYC infestation zones year-round.
Highest activity zones
SLF Hotspots in New Haven County, CT
Yale University campus (New Haven)
Active zone
I-91 / I-95 junction area
Active zone
Quinnipiac River valley
Active zone
Long Island Sound shoreline
Active zone
Metro-North New Haven Line terminus
Active zone
Primary SLF food source
Tree of Heaven in New Haven County, CT
Tree of Heaven is established along the I-91/I-95 corridor and Quinnipiac River valley margins throughout New Haven County, providing primary SLF dispersal pathways from Fairfield County populations northward and inland. Yale University campus edges and New Haven's urban street margins have Ailanthus colonization that supports SLF establishment in the city core. The Long Island Sound shoreline road margins and Metro-North New Haven Line rail embankments are priority monitoring zones as SLF populations continue to advance through this historically and academically significant Connecticut county.
Identify Tree of Heaven →Local action resources
What To Do in New Haven County, CT
Report a Sighting
Every sighting in New Haven County, CT maps the invasion front. Report directly to Connecticut Agricultural Experiment Station.
Report Now →Squish on Sight
See a spotted lanternfly? Kill it immediately — it is legal and encouraged in all states. Learn the best kill methods.
Full Fight Guide →Map ToH in Your Block
Tree of Heaven removal cuts off SLF food supply. Add ToH sightings to the community map to guide removal efforts.
View Sighting Map →Statewide resources
Full CT State Guide
County-level data, quarantine zones, treatment guides, and agency resources for the entire state.
See the full CT guide →Community intelligence
Live Sighting Map
See where SLF has been spotted near you in New Haven County, CT. Add your own sighting to help map the front.
Open the Map →Free weekly fight briefing
Fight SLF in New Haven County, CT.
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