Browntail Moth - Euproctis chrysorrhoea (L.)

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Browntail Awareness Month - A Success!

circle image that says I am a browntail moth buster! I clip browntail moth winter webs!  Department of Agriculture, Conservation & Forestry

Thank you for joining us this month to raise awareness and take action to reduce browntail moth impacts!

Browntail Moth Awareness Month may be over, but that doesn't mean browntail winter webs are gone!! Our efforts to raise awareness also continue.
Developing outreach materials that people of all ages will enjoy and learn from can be quite a challenge. That's why we're asking for your feedback on these sticker ideas!

Share your sticker feedback with us by taking the short survey:

Your Browntail Checklist for March:

  1. Recognize browntail moth winter webs on the branch tips of their favorite host trees (oak, elm, birch, poplar, cherry, fruit, and ornamentals).
  2. Remove the winter webs before the end of March while the rash-causing caterpillars are still inside and the trees are still dormant.
  3. Recruit help from a licensed arborist or an FAA certified commercial remote pilot with a specialized vehicle to remove webs out of your reach. If web removal isn't possible due to the height or quantity of winter webs, recruit a licensed pesticide applicator who can treat trees in early spring to kill the caterpillars. 
  4. Reach out to your neighbors, co-workers, or businesses if you recognize browntail moth winter webs so plans can be in place to remove the webs. 
  5. Take the Browntail Moth Sticker Feedback Survey to help us improve future stickers.
  6. Host a web-clipping event to clip browntail winter webs in your community. 
  7. Enjoy spring in your backyard with fewer browntail caterpillars

Still need help recognizing browntail winter webs?

  • Stand with the sun to your back and check out browntail's favorite host trees (oak, elm, birch, poplar, cherry, fruit and ornamentals). Look at the tips of branches for palm-sized webs wrapped tightly in white silk. The silk will reflect the sun and differentiate these current webs from older browntail webs or unfallen leaves (no silk reflection).
  • If you find current browntail webs, focus treatment on trees closest to your house and in high traffic areas such as your dooryard. 

Knowing where browntail winter webs are on your property and which trees have the most webs can help inform your management decisions, whether you do it yourself or recruit professional assistance.

Read More…

How to clip browntail moth webs/nests

TIP: Focus management on populations that will directly impact people, pets, and livestock or pose a high risk of contributing to spread.

Use extreme caution if burning webs. Only burn if the branches have been clipped off. This type of burning requires a burn permit. For more information, please visit and check the daily forest fire danger report.

2023 Browntail Moth Awareness Month Webinar

Contact 211 Maine for answers to frequently asked questions on browntail moths:

  • Dial 211 (or 207-874-2211)
  • Text your zip code to 898-211

Or visit our Browntail Moth FAQs.

More Browntail Moth Updates +

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Rulemaking: Browntail Moth Mitigation Fund

The Maine Forest Service is developing rules to administer the browntail moth mitigation funds.

The Fund was created to provide funding to government entities or nonprofit organizations to support the mitigation of browntail moth in areas of Maine with significant populations. The draft rule includes details on the types of organizations that can apply for funds, the application process, the types of activities that could be funded, and how funds will be disbursed.

View Draft Rules (PDF)

General Information

Adult browntail moth white with brown abdomenThe browntail moth is an insect of forest and human health concern which was accidently introduced into Somerville, Massachusetts from Europe in 1897. By 1913, the insect had spread to all of the New England states and New Brunswick and Nova Scotia. Since that time, populations of this pest slowly decreased due to natural controls until the 1960's, when browntail moth was limited to Cape Cod and a few islands off the Maine coast in Casco Bay. Browntail moth populations are again building in Maine and are found in patches along the coast and up to 60 miles inland from the western Maine border to the New Brunswick border, with the greatest concentrations in mid-coastal Maine and the capital region.

The larval stage (caterpillar) of this insect feeds on the foliage of hardwood trees and shrubs including: oak, shadbush, apple, cherry, beach plum, and rugosa rose. Larval feeding causes reduction of growth and occasional mortality of valued trees and shrubs. Learn More: How to Identify Maine’s Main Defoliating Caterpillars (YouTube) / Life Cycle of Browntail Moth (PDF)

While feeding damage may cause some concern, the primary impact on humans by browntail moth results from contact with poisonous hairs produced by the caterpillars. Microscopic, toxic hairs break off the caterpillars and can be airborne or settled on surfaces in browntail moth infested areas. Sensitive individuals who encounter the hairs may develop a skin rash similar to poison ivy and/or trouble breathing. Symptoms can last anywhere from a few hours to several weeks and can be severe in some individuals. Learn More: Maine CDC Browntail Moth Information

Frequently Asked Questions

Partners at Maine Forest Service, Maine Board of Pesticides Control, Maine Center for Disease Control, Cooperative Extension and others have put together an extensive list of frequently asked questions. Questions cover topics from biology, to management, to policy to pets.

What is the best time of year to clip webs? +

  • Late October to mid-April.
  • When the trees and shrubs are dormant.

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All Frequently Asked Questions

Maine 211 - Get Connected. Get Answers.For More Information:
Dial: 211 or 866-811-5695
Text Zip Code to 898-211

Management Techniques

Focus management on populations that will directly impact people, pets and livestock or pose a high risk of contributing to spread.

Use extreme caution if burning webs. Never burn unless the branches have been clipped off. This type of burning requires a burn permit. For more information, please visit and check the daily forest fire danger report.

For Smaller Trees & Shrubs +

Browntail web removal: Webs in small trees and shrubs, safely within reach of the ground, and without hazards such as powerlines, can be removed between October and April. Destroy webs once removed (burn, soak for an extended period in soapy water, or dispose of in trash). With permission, you can do this on properties you don’t own or manage. If there are hazards, or you need to leave the ground, this is work for a licensed arborist.

Browntail caterpillar treatment: If you miss the window for web removal, caterpillars can be treated with a variety of registered insecticides labeled for the type of application (such as ornamental tree or shrub, fruit tree) and effective in controlling caterpillars. Often browntail moth will not be on the label.

Applications must be consistent with the label directions. Consider hiring a licensed pesticide applicator. In most years, treatment should be effective (caterpillars killed) before late May. Later treatments do little to reduce both hairs in the environment and damage to hosts.

If you are managing browntail moth using pesticides within 250 feet of the mean high tide mark adjacent to coastal waters and extending upriver or upstream to the first bridge, additional rules apply.

If you are unlicensed, do not use this approach on properties that are not yours or are open to the public.

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For Webs in Taller Trees +

Hire professional help to treat webs out of reach or near hazards on the property you own or manage. Line up help during fall or winter.

Licensed Professional Arborists can remove BTM webs in larger trees and shrubs (October to April).

Arborist pruning browntail moth webs.

Unmanned Aerial Vehicle (UAV) Operators with an FAA Remote Pilot License may provide services using UAVs with attachments that physically remove webs.There is no requirement that these operators have knowledge of tree care. As in working with any professional, confirm your prospective contractor is adequately insured and qualified to provide the service.

For large trees, there are very limited insecticidal products (PDF) that are readily available to and applied by unlicensed individuals and that can legally be applied to target trees and life stages of browntail moth.** 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.

**Acecaps are not registered for use in Maine because the label does not meet federal standards for pesticide labeling. It is therefore not legal to use Acecaps. The Maine Board of Pesticides Control has provided support to the manufacturer to explain what needs to be changed to come into compliance and encouraged the manufacturer to work with EPA to bring their label up to standards. If we become aware of a change in status, we will update this message. You can check the current registration status by entering the product name in this database.**

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Where is Browntail Moth in Maine?

Maine Forest Service conducts surveys for browntail moth from small planes and from moving trucks. These are broad-scale surveys that do not completely cover the impacted area. To understand what is happening in your neighborhood, and whether you are at risk of exposure to browntail moth, learn to recognize browntail moth then inspect the trees around you. The best time of year to do this is in the winter from mid-December through March. Browntail moth is most recognizable at this stage and management can occur or be lined up ahead of the spring season.

Browntail Moth Interactive Map

Citizen Science Survey Protocol

Aerial Detection Survey Maps +

Winter Web Survey Maps +

For Towns and Organizations

Pruning browntail moth webs.

Focus management on populations that will directly impact people, pets and livestock or pose a high risk of contributing to spread.

Hire professional help to treat webs out of reach or near hazards on the property you own or manage. Line up help during fall or winter.

Social Media Toolkit +

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Got questions about browntail moth? 211 is there to answer them.

Know your enemy and your friends. #KnockOutBTM, not silkmoths.

Image credits: DACF except promethea larva BOMONA user Zelenaks, promethea adult BOMANA user JRTindall


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Learn how to safely remove and destroy browntail moth winter webs from the Maine Department of Agriculture, Conservation and Forestry at  #KnockOutBTM

To avoid encounters with the fuzzy caterpillars, remove and destroy browntail moth webs by April. Learn how from the Maine Department of Agriculture, Conservation and Forestry at  #KnockOutBTM

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#KnockOutBrowntail Business Challenge +

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Entomologists with the Maine Forest Service in the Department of Agriculture, Conservation and Forestry (DACF) have teamed up with the University of Maine to track the spread and investigate the causes of the outbreak and evaluate management strategies for this daunting pest.