PORTLAND, Maine - It's shaping up to be a bad year in southern and coastal Maine for the invasive winter moth. Some motorists report driving through clouds of the small, drab, flying insects, and others say the exterior walls of their homes are covered with the creatures, who make their way inside whenever the door opens.
Maine Department of Agriculture Forest Entomologist Charlene Donahue says the winter moths first began showing up in Maine in high numbers in a few locations only about four years ago.
Donahue says the mild weather and lack of ice and snow are contributing to this year's severe outbreak. She says the moths come out this time of year to mate and lay their eggs after spending six to eight months in cocoons in the ground.
"If the weather is really freezing cold, below freezing, if there's ice and snow on the ground, then the moths can't get out of the ground where they've been spending all summer and fall," she says.
Donahue says the the moths have expanded their range. She says there are reports of the insects from Kittery to Harpswell, and on some Casco Bay Islands as well as Vinalhaven Island.
Donahue says the moths being seen right now will yield caterpillars next May that will eat the leaves of oak, maple and ash trees, and some fruit-bearing trees, such as apple.
Donahue says not much can be done about winter moths this time of year. She says trees can be protected with horticultural oil and biological pesticides. In addition, she says, the state continues to release parasitic flies to control winter moths, but says it takes seven to ten years for them to become effective.
