Spotted Lanternfly inWarren County, NJSPOTTED LANTERNFLY GUIDE
Warren County is northwestern New Jersey's most rural county — confirmed for SLF in 2021, later to establish than eastern New Jersey counties, but facing increasing pressure as the infestation front advances. Belvidere is the county seat. Delaware Water Gap National Recreation Area anchors the county's western border, where SLF populations from the Lehigh Valley in Pennsylvania have crossed the Delaware River. The I-80 corridor is a critical spread vector, bringing SLF westbound from established populations in Lehigh County, PA and eastbound from the growing Warren County zone into Morris and Sussex counties. The county's rural character means SLF can establish and expand before being detected.
Highest activity zones
SLF Hotspots in Warren County, NJ
Delaware Water Gap NRA
Active zone
Kittatinny Mountain corridor
Active zone
Swartswood State Park
Active zone
Pequest Wildlife Management Area
Active zone
I-80 corridor
Active zone
Primary SLF food source
Tree of Heaven in Warren County, NJ
Tree of Heaven is present along the Delaware River corridor in Warren County and along the I-80 road margin from the Delaware Water Gap eastward. Kittatinny Mountain corridor road margins and the Pequest River valley have Ailanthus populations that extend SLF habitat into upland zones. Swartswood State Park edges and the Pequest Wildlife Management Area boundary margins are priority monitoring zones as SLF continues to establish across this rural northwestern county.
Identify Tree of Heaven →Local action resources
What To Do in Warren County, NJ
Report a Sighting
Every sighting in Warren County, NJ maps the invasion front. Report directly to NJ Department of Agriculture.
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 NJ State Guide
County-level data, quarantine zones, treatment guides, and agency resources for the entire state.
See the full NJ guide →Community intelligence
Live Sighting Map
See where SLF has been spotted near you in Warren County, NJ. Add your own sighting to help map the front.
Open the Map →Free weekly fight briefing
Fight SLF in Warren County, NJ.
One email per week. Your zip code. Your threat level. Your action plan. Know exactly what to do this week in Warren County, NJ.