DEM confirmed the leaves on this tree next to the School Department had been hit by the winter moth. Credit: EG News
First I noticed light green inchworms just kind of appearing (on the window sill, on my arm, in my hair), then I started noticing holes in the leaves on trees all around. An email from Tom at the library connected the dots (thanks, Tom!).
Turns out the winter moth caterpillar’s taken a liking to the trees on the Hill and all over the state, according to the state Dept. of Environmental Management, causing defoliation on oak, maple, ash, basswood, elm, beech and fruit trees. “Leaves on affected trees are filled with small holes and have a shotgun-hole appearance,” the DEM said in a press release.
DEM, URI and UMass Amherst are fighting back – for the past three years, they’ve been releasing a parasitoid fly that feeds exclusively on winter moth in early May throughout Rhode Island. Of course, that won’t repair those holey leaves (and yes, holey is a word). But – eventually – it should help. The fly, cyzenis albicans, is a natural enemy of the winter moth and has been effective in mitigating large populations of winter moths in Nova Scotia, according to DEM. But it will take several years for populations of the parasite to catch up with the winter moths.
A tree on Church Street.
In the meantime, if you think your trees have been hit by the winter moth caterpillar, send an email Bruce Payton at [email protected] or Paul Ricard [email protected], giving the location, along with a contact name and phone number. They will use the information to help target fly releases next year.
As for this year, Payton said that heavily defoliated trees will be stressed, so to make sure they get enough water, especially if we end up having a dry summer.
Do NOT fertilize defoliated trees, he said. And don’t give up on your trees either. Just give them plenty of water and sit tight until next year.