Pests to know in Duluth
Termites in Duluth
University of Minnesota Extension says termites are generally uncommon in Minnesota, more common in the south and rare to non-existent farther north.[1]
Invasive species reported here
- The City of Duluth says emerald ash borer was detected in Duluth in late 2015, though later infestations suggest it had been present for a few years.[6]
- Duluth is testing stingless wasps that eat emerald ash borer larvae as a biological control, with the trial limited to Hartley Park.[6]
- The Minnesota Department of Agriculture's spongy moth timeline lists 1969 as the year the first signs, egg masses and pupal cases, appeared in Duluth.[7]
- MDA says Cook and Lake counties have permanent, established spongy moth populations and are under formal quarantine.[8]
Climate
Central Duluth (ZIP 55802) is in USDA plant hardiness zone 5a, where the average coldest winter night is -20 to -15°F.[12]
Public agencies that handle pests
- St. Louis County Public Health asks law enforcement and medical staff to submit animal bite referrals to its office within 24 hours of the incident.[2]
- The Minnesota Department of Health says most tickborne diseases in the state come from bites of infected blacklegged (deer) ticks.[3]
- MDH reports that dead bird reporting and virus testing since 2002 confirmed West Nile virus is widely established across Minnesota.[5]
Hiring a licensed company
Free local help
University of Minnesota Extension calls the multicolored Asian lady beetle a nuisance in Minnesota, clustering on buildings in large numbers each fall to find winter shelter.[11]
Through the year
- Spring to Fall
- MDH says adult ticks in Minnesota emerge after snowmelt, peak in May, stay active through June, and return from late September through October.[4]
Sources
- University of Minnesota Extension, “Termite workers.” apps.extension.umn.edu/garden/diagnose/insect/indoor/beetles/small/termiteworker.html (accessed 2026-10-06)
- St. Louis County Public Health, “Animal Bite Referral to St. Louis County Public Health.” apps.stlouiscountymn.gov/animalbitereferral/ (accessed 2026-10-06)
- Minnesota Department of Health, “Tickborne Diseases.” www.health.state.mn.us/diseases/tickborne/index.html (accessed 2026-10-06)
- Minnesota Department of Health, “Ticks in Minnesota.” www.health.state.mn.us/diseases/tickborne/ticks.html (accessed 2026-10-06)
- Minnesota Department of Health, “West Nile Virus.” www.health.state.mn.us/diseases/westnile/index.html (accessed 2026-10-06)
- City of Duluth Parks & Recreation, “Emerald Ash Borer (EAB).” duluthmn.gov/parks/natural-resources/invasive-species/eab/ (accessed 2026-10-06)
- Minnesota Department of Agriculture, “Spongy Moth Insect Info and History.” www.mda.state.mn.us/spongymothbiology (accessed 2026-10-06)
- Minnesota Department of Agriculture, “Spongy Moth Quarantine.” www.mda.state.mn.us/spongymothregs (accessed 2026-10-06)
- Minnesota Office of the Revisor of Statutes, “Minnesota Statutes 18B.32 Structural Pest Control License.” www.revisor.mn.gov/statutes/cite/18B.32 (accessed 2026-10-06)
- City of Duluth City Clerk, “Animal Licensing.” duluthmn.gov/city-clerk/licenses-permits/animal-licensing/ (accessed 2026-10-06)
- University of Minnesota Extension, “Multicolored Asian lady beetles.” extension.umn.edu/garden-and-home/yard-and-garden/yard-and-garden-insects/multicolored-asian-lady-beetles (accessed 2026-10-06)
- USDA ARS and PRISM, via phzmapi.org, “Plant hardiness zone for ZIP 55802 (2023 USDA map data).” phzmapi.org/55802.json (accessed 2026-10-06)
- National Pesticide Information Center, “State Pesticide Regulatory Agencies.” npic.orst.edu/reg/state_agencies.html (accessed 2026-10-06)