Common species in Wisconsin
Wisconsin follows the state health led source pattern. The species below are drawn from the state-authority sources listed in the sidebar Data Row.
- Lone star tick (northward expansion + unusual-submission context)
- Asian longhorned tick (only if DATCP, WI DNR, or USDA source support is added)
When ticks are most active
Broad caution April through October. Blacklegged tick nymphs peak May-July; adult blacklegged ticks are active spring and fall and can move on warm winter days; American dog ticks are emphasized in spring and early summer.
Where you're most likely to encounter ticks
Northwoods cabin and lake weekends, hunting and fishing camps, Door County and Apostle Islands hiking, Driftless Area forest trails, Madison and Milwaukee suburban edges, tall-grass dog walks, brushy field margins, Mississippi River bluff trails, and Minnesota- or Michigan-border exposure.
Disease context
Each disease named below carries an evidence tag per the Data Row policy. Pills indicate the strength of state-specific evidence, not the severity of the disease. Symptoms should always be routed to a clinician; this is orientation, not diagnosis.
- Lyme diseasestate surveillance confirmed
WI DHS reports Lyme as the most commonly reported tickborne disease in Wisconsin; among the top high-incidence states nationally
- Anaplasmosisstate surveillance confirmed
- Babesiosisstate surveillance confirmed
- Powassan virus diseasestate surveillance confirmed
- Ehrlichiosisstate surveillance confirmed
- Hard tick relapsing feverstate surveillance confirmed
- Borrelia mayoniistate unique angle
Mayo Clinic / Pritt et al. discovery; CDC archive and WI DHS report exposure documented in Wisconsin alongside Minnesota — the Upper Midwest moat fact
- Rocky Mountain spotted fevernon diagnostic mention only
- Tularemianon diagnostic mention only
If you find a tick — what to do
Map resolution notes
mixed resolution.WI DHS supports statewide, regional, and high-incidence Lyme/blacklegged claims at the county level for many counties; CDC maps support national comparison; UW-Madison Medical Entomology supports surveillance-study-specific resolution. Do not infer fine-grained county or neighborhood risk from generic state presence alone; cite WI DHS county data when making county-level claims.
State sources
- Primary species source
- Wisconsin DHS "Tick-borne Diseases" hub and DHS tick identification fact sheets for state tick species, distribution, and surveillance framing; UW-Madison Division of Extension supports biology and practical prevention nuance.
- Primary health source
- Wisconsin DHS "Tick-borne Diseases" hub, DHS Lyme Disease and Anaplasmosis surveillance reports, and DHS public-health guidance for disease/surveillance framing; CDC disease pages and maps provide national guardrails.
- Primary extension source
- UW-Madison Division of Extension publications on ticks, tick prevention, and yard/garden tick management for biology, life-stages, and habitat-management context.
- Surveillance
- WI DHS tickborne disease statistics and county-level surveillance reports; UW-Madison Medical Entomology lab for academic surveillance context; WI DNR for wildlife/habitat context; CDC for national comparison; CDC archive + Pritt et al. + Mayo Clinic News Network for Borrelia mayonii context.