Browntail moth has been in Maine since 1904 and has been in an outbreak phase over a broader area since 2015.[1] The Maine Forest Service has found it in all 16 counties, including Cumberland County.[2] Populations can be heavy on one street and light on the next, so the best way to know about the trees around your Yarmouth home is to look for winter webs. The Maine Forest Service also keeps a map of known populations.[3]
In 2026, Maine CDC reported higher browntail moth populations in parts of Cumberland County, along with parts of Androscoggin, Hancock and Oxford counties, even as populations statewide have been steadily decreasing over the past couple of years.[4] The Maine Forest Service’s 2026 aerial survey found localized defoliation mainly along the western shores of Sebago Lake.[5]
Browntail moth control for Yarmouth properties
Spray or injection?
Both are used for browntail moth in Maine. Near wells, the Maine Forest Service advises using tree injection rather than foliar spray or soil drench, to reduce off-site movement.[6] Speed and length of protection vary by product: some act within minutes and others take weeks, and injected products can remain active in trees anywhere from two weeks to two years.[6] One thing to avoid: insecticide capsules sold as Acecaps are not registered for use in Maine.[3]
Within 250 feet of the mean high tide mark along coastal waters, and upriver to the first bridge, additional rules apply to browntail moth treatments.[3] Like much of coastal Maine, Yarmouth has many properties close to the water, so treatment has to be chosen with care.
Why hire a professional?
Many webs sit at the very tops of tall oaks, well out of reach of a pole pruner. Maine also requires insecticide applications to be made by licensed pesticide applicators, except when you treat your own property with general-use products, and you cannot treat a neighbor’s trees unless you are licensed.[6] A licensed professional can reach high webs safely and choose a treatment that fits your property.
Want the full picture? Read our complete guide to browntail moth treatment in Southern Maine.
Browntail moth and Yarmouth
Browntail Moth help near Yarmouth
Tree Medics is based in Biddeford and works throughout Southern Maine. We also offer browntail moth services in nearby towns:
See all tree care in Yarmouth.
Sources
- Maine Forest Service: Browntail moth management overview
- Maine CDC & Maine Forest Service: Browntail moth hairs pose risk during spring outdoor activities
- Maine Forest Service: Browntail moth information, treatment timing and map of known populations
- Maine CDC Health Advisory: Browntail moth (May 2026)
- Maine Forest Service: Forest & shade tree conditions, August 2026
- Maine Forest Service: Browntail moth frequently asked questions
- Town of Yarmouth: Browntail Moth Caterpillar (BTM)
