Spotted Lanternfly inFrederick County, MDSPOTTED LANTERNFLY GUIDE
Frederick County is part of Maryland's expanding SLF zone, confirmed in 2023 as populations pushed west and north from the Montgomery County core along the I-270 corridor. Frederick — one of Maryland's fastest-growing counties — combines historic downtown character with rapidly expanding suburban development and significant agricultural land. The I-270 Tech Corridor has been a primary vector for SLF introduction from Montgomery County, and the Monocacy River valley provides a natural spread pathway through agricultural and parkland areas. Catoctin Mountain Park and Appalachian Trail crossings are priority monitoring zones as SLF approaches the western mountain barrier.
Maryland issued a statewide quarantine in March 2026. All movement of regulated articles from Frederick County requires a permit from MD MDA.
Highest activity zones
SLF Hotspots in Frederick County, MD
Monocacy National Battlefield
Active zone
Catoctin Mountain Park
Active zone
Frederick City waterfront
Active zone
I-270 Tech Corridor
Active zone
Appalachian Trail crossings
Active zone
Primary SLF food source
Tree of Heaven in Frederick County, MD
Tree of Heaven is established along the I-270 corridor and Monocacy River valley margins in Frederick County, providing SLF dispersal pathways from the established Montgomery County population into the Frederick City area. The Frederick City waterfront along Carroll Creek has Ailanthus colonization in urban margins. Catoctin Mountain Park edges and road margins near Appalachian Trail crossings have ToH populations that raise concerns about SLF establishment in higher-elevation habitat as the infestation frontier expands westward.
Identify Tree of Heaven →Local action resources
What To Do in Frederick County, MD
Report a Sighting
Every sighting in Frederick County, MD maps the invasion front. Report directly to MD MDA.
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 Frederick County, MD. Add your own sighting to help map the front.
Open the Map →Free weekly fight briefing
Fight SLF in Frederick County, MD.
One email per week. Your zip code. Your threat level. Your action plan. Know exactly what to do this week in Frederick County, MD.