Invasive Emerald Ash Borer Confirmed For First Time In Vermont

Mar 1, 2018

This week, the Vermont Agency of Natural Resources announced that the invasive Emerald Ash Borer has been confirmed in the state.  Officials are not surprised by the discovery, but they are disappointed.

Ash trees make up about 5 percent of Vermont forest lands and are also common in urban areas.  The Emerald Ash Borer threatens all ash species in the state – white, green and black ash. It has no natural predators nor are there known effective controls.

Vermont Agency of Agriculture Food and Markets State Pest Survey Coordinator Emilie Inoue expects the pest will eventually kill all the ash trees in the state.  “Given the nature of this insect pretty much a hundred percent of those ash trees are going to die. There may be a few trees left. Unfortunately the vast maturity of ash trees within North America, in the states that are being hammered right now, most of them aren't showing any sort of resistance. There does seem to be a little bit here and there but unfortunately when an Emerald Ash Borer arrives it does do a pretty good job in terms of getting to and finding all the ash trees and killing them within three to five years once they infest it.”

The Emerald Ash Borer threatens only ash trees. Inoue explains that it’s the larval form of the beetle that threatens the trees.  “What happens is after the egg hatches and the larvae tunnels through underneath the bark, the larva actually feeds on that layer of tissues that brings all the water and nutrients up to the canopy of the tree. So when you get a heavy infestation you have a lot of larvae in there tunneling away and what ends up happening is it is essentially strangled.”

Vermont Department of Forest Parks and Recreation Forest Health Program Manager Barbara Schultz has expected the Emerald Ash Borer to enter the state for a long time, noting it is in 32 states and had already been confirmed in Quebec and the surrounding states of New York, New Hampshire and Massachusetts.  “This is a tree killer and the generation of ash trees we have now we're going to see a lot of impact on those trees. My hope is that the next generation will fare better. There are these natural enemies that have been introduced. We hope that they will be around and established by the time the next ash trees grow up and maybe those ash trees will have some resistance.  Surviving ash are around. We hope that maybe that indicates there’s some genetic resistance as well. So we will see a lot of dead ash trees but I'm hoping that those two facts will allow us to see another generation of ash come up.”

While Vermont had placed purple traps amid trees to try to detect the Emerald Ash Borer, Inoue says it was confirmed after a private forestry consultant reported a possible infestation to the state’s invasives website.  “Within twenty four hours of reporting it on site we were able to take a look at the photos that he had submitted and we were out there looking at it actually trying to figure out if this was EAB (Emerald Ash Borer) and it turned out that it was.”

State and federal officials are implementing an emergency action plan to respond to the EAB’s appearance in Vermont.  It will determine the extent of the infestation and outline quarantine and management options.