Calling all Birders: Be on the lookout for invasive forest pests!

The Vermont Urban & Community Forestry Program and VTInvasives are joining state agricultural and forestry agencies around the county asking birders to look for signs of damage from two invasive tree pests, emerald ash borer and Asian longhorned beetle, during the Christmas Bird Count and other birding activities this winter. “The Christmas Bird Count is an ideal opportunity for bird watchers to check the trees for signs of invasive pests,” said Jennifer Forman Orth, State Plant Pest Survey Coordinator at the Massachusetts Department of Agricultural Resources.

She continues: “The damage from these insects can easily be seen in winter, when there are no leaves on the trees, and birdwatchers are typically armed with a pair of binoculars that will help them check high-up branches for the perfectly round holes left by Asian longhorned beetles in maples and other hardwoods, or the increased woodpecker activity and removal of bark (“blonding”) caused by excessive woodpecker activity associated with emerald ash borer infestations in ash trees.”

According to staff scientists with NH Audubon, four bird species are particularly helpful in detecting infestations of emerald ash borer on ash trees: red-bellied and hairy woodpeckers, will strip off larger segments of bark from ash trees, while downy woodpeckers and nuthatches will remove smaller patches of bark.

If you are going out to watch or count birds this winter, please download the free Birdwatcher’s Field Guide to Holes in Trees, a handout produced by The Nature Conservancy. This one-page guide explains the differences between holes made by typical woodpecker and sapsucker foraging, holes made by woodpeckers seeking invasive insect larvae, and holes caused by the invasive insects themselves.

Birders are encouraged to take digital photos of any damage potentially related to forest insects, identify the species of tree with the damage if possible, and submit photos via the ReportIt link on the website.

Go to for more information on emerald ash borer, Asian longhorned beetle, and other invasive forest pests in Vermont.

Article adapted with permission from Leigh Greenwood, The Nature Conservancy,