Spotted Lanternfly inHarford County, MDSPOTTED LANTERNFLY GUIDE
Harford County is a heavily infested Maryland county confirmed for SLF in 2022, positioned along the critical I-95 northeast corridor between Baltimore and the Pennsylvania state line. Aberdeen Proving Ground — a major U.S. Army installation occupying extensive restricted-access land — creates significant monitoring challenges as Ailanthus can establish unchecked on military installation grounds, producing SLF reservoirs adjacent to the surrounding community. Susquehanna River State Park offers exceptional wildlife habitat along the lower Susquehanna, but also represents a major SLF spread corridor connecting Pennsylvania's heavily infested York and Lancaster counties to the Maryland quarantine zone. The county's mix of suburban growth, military presence, and natural lands creates a complex SLF management landscape. Harford County is part of Maryland's statewide quarantine in effect since March 2026.
Maryland is under a statewide spotted lanternfly quarantine as of March 2026. Moving regulated articles — including plants, yard waste, and outdoor items — out of Maryland requires inspection.
Highest activity zones
SLF Hotspots in Harford County, MD
Aberdeen Proving Ground perimeter
Active zone
Susquehanna River State Park
Active zone
I-95 northeast corridor
Active zone
Bel Air downtown area
Active zone
Gunpowder Falls State Park
Active zone
Primary SLF food source
Tree of Heaven in Harford County, MD
Tree of Heaven is established along Harford County's I-95 corridor, Susquehanna River margins, and road rights-of-way throughout the county, providing SLF dispersal pathways from the Pennsylvania state line southward toward Baltimore. The Aberdeen Proving Ground fence-line and buffer zone margins are a high-priority monitoring concern — Ailanthus colonizes restricted-access military lands that can serve as large-scale SLF reservoirs. Gunpowder Falls State Park edges and Bel Air area stream corridors have additional ToH populations that fuel SLF spread through the county's suburban and natural area interface zones.
Identify Tree of Heaven →Local action resources
What To Do in Harford County, MD
Report a Sighting
Every sighting in Harford County, MD maps the invasion front. Report directly to Maryland 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 MD State Guide
County-level data, quarantine zones, treatment guides, and agency resources for the entire state.
See the full MD guide →Community intelligence
Live Sighting Map
See where SLF has been spotted near you in Harford County, MD. Add your own sighting to help map the front.
Open the Map →Free weekly fight briefing
Fight SLF in Harford County, MD.
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