UMass Researchers Say They've Gotten Rid Of Winter Moth Problem -- Without Pesticides

Sep 6, 2018

UMass Amherst insect researchers say they've eliminated the threat of the winter moth -- which feeds on maple, oak, and other trees -- without the use of pesticides.

Winter moth came to New England from Europe in the 1990s, possibly by hitching a ride on a nursery plant, according to UMass entomologist Joseph Elkinton.

In its caterpillar form, the moth was destroying shade trees and blueberry plants, mostly along the coast.

For 14 years, Elkinton -- with USDA funding -- has been developing what's called a "biocontrol" method against the pest.

Based on a previous outbreak in Nova Scotia, Elkinton's lab introduced a parasitic fly that preys on the moth.

"You want to make sure that the thing you introduce is not going to become a problem in its own right," Elkinton said. "But the beauty of this particular fly we've been working with is that it attacks only winter moths, and not other species."

A shade tree on Cape Cod defoliated by winter moth.
Credit Joseph Elkinton / University of Massachusetts Amherst
A fly and fly puparia inside a winter moth pupa.
Credit Nicholas Condor / University of Massachusetts Amherst

Now that the fly has been successfully released into the environment, and the moth rendered a "non-pest," Elkinton said homeowners can avoid the cost and harm of pesticides.

His lab will now help develop biocontrol methods against the gypsy moth and other invasive insects.