Spotted Lanternfly inMilwaukee County, WISPOTTED LANTERNFLY GUIDE
Milwaukee County is Wisconsin's most populous county and the primary gateway for spotted lanternfly advancing westward from the heavily infested Chicago metro and northern Illinois. Established as a watch zone in 2025, Milwaukee sits at the convergence of I-94 and I-43 — two of the busiest freight corridors connecting Illinois to the upper Midwest. The Port of Milwaukee on Lake Michigan receives interstate shipping and cargo that has historically served as an introduction vector for invasive species. Milwaukee's dense urban core, mature tree canopy, and extensive rail network connecting to Union Pacific and BNSF mainlines make early monitoring and rapid response essential to preventing SLF from establishing permanent populations in Wisconsin.
Highest activity zones
SLF Hotspots in Milwaukee County, WI
Milwaukee downtown
Active zone
Wauwatosa
Active zone
West Allis
Active zone
South Milwaukee
Active zone
Oak Creek
Active zone
Primary SLF food source
Tree of Heaven in Milwaukee County, WI
Tree of Heaven is present along Milwaukee River corridor greenways, I-94 and I-43 highway margins, and Union Pacific and BNSF rail line rights-of-way through the metro. Lake Michigan shipping port facilities and intermodal yards in the Milwaukee metro are priority survey locations. The Milwaukee River and Kinnickinnic River stream valleys provide natural Ailanthus dispersal corridors through the urban core.
Identify Tree of Heaven →Local action resources
What To Do in Milwaukee County, WI
Report a Sighting
Every sighting in Milwaukee County, WI maps the invasion front. Report directly to Wisconsin Dept 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 WI State Guide
County-level data, quarantine zones, treatment guides, and agency resources for the entire state.
See the full WI guide →Community intelligence
Live Sighting Map
See where SLF has been spotted near you in Milwaukee County, WI. Add your own sighting to help map the front.
Open the Map →Free weekly fight briefing
Fight SLF in Milwaukee County, WI.
One email per week. Your zip code. Your threat level. Your action plan. Know exactly what to do this week in Milwaukee County, WI.