May 2019 - Author Urban Tree

In recent years the Browntail Moth population has been on the rise in southern coastal Maine. This is a concern because not only are they voracious eaters, but they pose a health risk to many individuals.

A bit of history on the presence of these insects in our area:

The invasive caterpillar was first introduced in Somerville, Massachusetts in 1897. By 1914 it had spread south to Cape Cod and north into the mid-coast of Maine. Through extensive management practices, by the 1950s the population had retreated to the islands of Casco Bay, ME and Cape Cod. While there have been occasional outbreaks since then, the population has been held largely kept in check. In recent years however, and for reasons unknown to biologists, the caterpillars have returned in force to the mid and southern coasts of Maine.

Browntail Moth

Since 2015 Browntail Moths have been found along coastal Maine, from Kittery to Trenton. The potential health hazard comes from their microscopic hairs that break off from the caterpillar, are released in the air and distributed via wind. They collect on all surfaces; lawns, garden plants, decks and clothes drying on the line. These hairs frequently cause a skin rash similar to poison ivy. For people with sensitive respiratory systems, the hairs can cause serious breathing difficulties when inhaled. The effects of the hairs can last anywhere from a few hours to several weeks depending on the sensitivity of the person.

Browntail Moth web

Identification is easiest during the winter when the leaves are off the trees and the webs are easy to spot dangling off the end of the twigs. (see photo) The caterpillars grow to be 1.5” in length, are dark brown with a white stripe down each side and two red dots on the back. They are seen from August to the following June. The adult moths are found in July and August, they have white wings and a tuft of dark brown hair on the abdomen.

If you think you might have Browntail Moths, please do not hesitate to contact Urban Tree Service. One of our licensed professionals will help identify if the caterpillars are present and establish a treatment plan keeping your family and friends safe when enjoying the outdoors!