AUGUSTA — February 2022 has been recognized as Browntail Moth Awareness Month in Maine to encourage people to take advantage of the dormant season of the insect and join together to reduce impacts from browntail moth (BTM).
BTM populations in Maine have been in an outbreak phase since 2015 and the pest cannot be eradicated. Most areas of Maine, especially settled areas with significant host tree populations such as oak, apple, crabapple, pear, birch, cherry, or other hardwoods, are at risk of infestation by the caterpillars. While long-lasting tree defoliation and branch dieback are major concerns, BTM’s microscopic, toxic hairs can cause trouble breathing and skin irritation similar to poison ivy from a few hours up to several weeks.
The Maine Forest Service (MFS) Forest Health and Monitoring Division coordinates within state government, local communities, and directly with citizens to respond to this issue. Winter is the best time to clip and destroy BTM winter webs within reach or hire licensed arborists or pesticide applicators to reduce out-of-reach populations. Comprehensive BTM information and tools compiled by MFS, Board of Pesticides Control, Maine Center for Disease Control, the University of Maine and other partners including research, infestation tracking, FAQs, and educational resources for communities, municipalities, businesses, and healthcare providers, are available on maine.gov/dacf/knockoutbtm.
Follow the Four Rs to “Knock Out BTM” In Our Communities and Reduce the Itch!
Recognize: Learn how to tell if the trees where you live, work, and play have BTM. Their winter webs can look like single leaves hanging onto twigs or fist-sized clumps of leaves tied together tightly with silk. Knowing where the nests are in your yard or town can help inform your management decisions. Learn more by participating in the BTM Awareness Month events included below.
Remove: With permission, use hand snips or extendable pole pruners to remove webs within reach from the ground and away from hazards such as powerlines. Protect your eyes and skin from hairs that might be present from past caterpillar activity. After removal, destroy webs by burning or soaking in soapy water for several days, then dispose of the nests in the trash.
Recruit: Hire professional help to treat webs out of reach or near hazards on the property you own or manage. Line up help during winter. Licensed Professional Arborists can remove BTM webs in larger trees and shrubs in the winter. In trees where the caterpillars’ hairs cause a nuisance and where it is not practical to remove the webs, Licensed Pesticide Applicators may be able to use insecticides during the growing season to manage BTM.
Reach Out: If you find BTM in your neighborhood, let your neighbors and town officials know. The more neighbors, businesses, and others get together to respond to the problem, the better the results.
Encounters with hairs from BTM caterpillars can cause mild to severe rashes and respiratory issues. Some people say they experience itching with fewer than ten webs per tree or shrub; others say they have no symptoms from heavier infestations around their yards.
Everyone is invited to participate in the following BTM Awareness Month events or set up community events. Use #KnockOutBTM on social media to share your efforts. Some ideas for activities include mapping infestations on the town and public properties, hosting public service web-clipping events, creating contests for the most webs clipped or other community, and knowledge building activities.
BTM Awareness Month Events
January 27, 2022, 11 AM
Tune in to Maine Public Broadcasting’s Maine Calling for a conversation about BTM. Episodes are rebroadcast at 7pm and past episodes are available on-demand.
February 1, 2022, 12 to 1 PM
Piscataquis County Soil and Water Conservation District will host MFS Forest Entomologist Tom Schmeelk for a webinar discussion on BTM, Emerald Ash Borer and ticks, issues of growing concern in the region. Register now or contact the district for more information (207-564-2321, Ext. 3.)
February 1, 2022, 6:30 to 8 PM
Belfast Free Public Library will host MFS Forest Entomologist Tom Schmeelk for webinar on BTM and Emerald Ash Borer, two invasive insects of significant concern. Learn more and register on the library website.
February 2, 2022, 6:30 PM
Hallowell Conservation Commission is hosting MFS Forest Entomologist Tom Schmeelk for an Informational Meeting on BTM, open to the public.
February 8, 2022, 12 to 1 PM
Visit the Viles Arboretum in Augusta to learn steps you can take to manage BTM in your area. MFS Forest Entomologist Tom Schmeelk will discuss Integrated Pest Management of BTM. Check the events page on the arboretum website for details.
February 10, 2022, 4 PM
Blue Hill Heritage Trust, Island Heritage Trust, Hancock County Soil and Water Conservation District, Great Pond Mountain Conservation Trust, and Frenchman Bay Conservancy are hosting a conversation bout BTM in the region with State Entomologist and Director of MFS Forest Health and Monitoring Allison Kanoti. A brief overview of the problem and management approaches will be presented. Register for this webinar.
February 16, 2022, 9:15 to 10:15 AM
University of Massachusetts’ Cooperative Extension program is hosting MFS Forest Entomologist Tom Schmeelk to talk about BTM and What You Should Know. Details may be found on the Extension’s events web page.
February 17, 2022, 7 PM
The Lewiston Auburn Community Forestry Board (LACFB) and Auburn Conservation Commission are teaming up to host an evening discussion on BTM and other invasive pests with Director of MFS Forest Health and Monitoring Allison Kanoti. Meeting details to be announced. LACFB will be coordinating a field session in March, details to be determined.
February 23, 2022
BTM and other insects and diseases of ornamental and forest trees will be topics of discussion at the MELNA educational workshop in Portland. Details will follow on the MELNA website.
February 24, 2022, 9 AM to 12 PM
The Maine Municipal Association is sponsoring the Tackling Environmental Challenges in Your Community webinar covering the topics of BTM, Emerald Ash Borer and Vernal Pools. Registration fee. More information is available on the MMA website.
March 5, 2022
Maine Arborist Association is planning a return to their annual in-person meeting March 5 in Portland, ME. Maine Forest Service will provide updates on topics including BTM, forest health and Project Canopy. Visit the MAA website for updates and registration details.
For more information:
Contact 211 Maine for answers to BTM FAQs:
- Call 211 or 1-877-463-6207
- Text your ZIP code to 898-211
Or visit the MFS website. While you are there, sign up for the BTM News Bulletin.
–Maine Department of Agriculture, Conservation and Forestry