Common species in New Hampshire
New Hampshire follows the shared source pattern. The species below are drawn from the state-authority sources listed in the sidebar Data Row.
- Woodchuck tick
- Brown dog tick
- Lone star tick (where NH DHHS or UNH document local establishment or expansion)
- Asian longhorned tick (animal/livestock context)
When ticks are most active
Blacklegged tick: nymph activity May through July is the highest-risk window for human Lyme exposure, with adult activity in spring and fall. American dog tick: most active spring through mid-summer, with May to early July as the practical peak. Broad prevention caution spring through fall, with adult blacklegged tick activity continuing on any day above freezing.
Where you're most likely to encounter ticks
White Mountain and southern NH forests, wooded and grassy trail edges, low forest vegetation along leaf litter, stone walls and brushy yard edges, dog walking, hiking, hunting, and yard/garden work near woods.
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
- Anaplasmosisstate surveillance confirmed
- Babesiosisstate surveillance confirmed
- Powassan virus diseasestate surveillance confirmed
- Ehrlichiosisregional pattern
- Rocky Mountain spotted fevernon diagnostic mention only
- Tularemianon diagnostic mention only
- Borrelia miyamotoi diseaseregional pattern
- Alpha-gal syndromeregional pattern
If you find a tick — what to do
Map resolution notes
mixed resolution.NH DHHS, UNH Extension, and CDC sources support state-level and some regional statements, but not all species, disease, density, or expansion claims are county-supported. Use county-level claims only where an official county-level source supports that exact field; keep general species/range claims at state or regional level when the source resolution is broader.
State sources
- Primary species source
- NH DHHS Bureau of Infectious Disease Control tick and tickborne disease pages for state species framing; UNH Cooperative Extension tick resources for seasonal, habitat, and expansion nuance.
- Primary health source
- NH DHHS tickborne disease pages and clinician reference materials for disease and clinician-routing context; CDC tickborne disease pages for national context.
- Primary extension source
- UNH Cooperative Extension tick fact sheets and yard/landscape guidance for species activity, habitat, prevention, and removal detail.
- Surveillance
- NH DHHS tickborne disease surveillance summaries, CDC NNDSS for Lyme/anaplasmosis/babesiosis/Powassan counts, CDC Where Ticks Live, and UNH Extension tick resources where map or surveillance context is used.