Evidence of hemlock woolly adelgid on hemlock. (Connecticut Agricultural Experiment Station Archive, Connecticut Agricultural Experiment Station / ©
Evidence of hemlock woolly adelgid on hemlock. (Connecticut Agricultural Experiment Station Archive, Connecticut Agricultural Experiment Station / © Bugwood.org)
Monday January 14, 2013

PUTNEY -- As Forest Protection Forester with the Vermont Department of Forests, Parks and Recreation, it is Jim Esden's job to track the spread of the hemlock woolly adelgid, an invasive insect that feeds on the sap of hemlock trees.

First discovered in Vermont in 2007, the insect has been showing up in greater numbers and was first discovered in Bennington County last year.

After a relatively slow and steady increase in the area that is infested in Vermont, last year, the number of towns where the insect has been confirmed doubled.

Everyone knew that it was only a matter of time before it was found farther north, Esden said.

The hemlock woolly adelgid has no natural predators, but Esden said that cold weather was one of the tools the state had to slow the spread.

Last year during the historically warm winter Esden said the insect survived in much grater numbers and now the adelgid has been found in Putney.

"There was a very low mortality rate last year and now we are seeing a large expansion of the area known to be infested," Esden said. "A good deal of Windham County is infested now."

He will come to town on Tuesday, Jan. 15, at 6:30 p.m. to lead a discussion at the Putney Fire Station on the hemlock woolly adelgid.

Esden said a few Putney residents saw signs of the hemlock woolly adelgid along Aiken Road in November.

Citizen involvement is the most important method the state has to monitor the thousands of acres of forest land in Vermont, said Esden, and the meeting is a way to get more people involved in monitoring the woods.

Esden says he will have photos of the tell-tale white, fuzzy insect and he will tell people what they are supposed to do if they see signs of the adelgid.

The state has been experimenting with releasing a beetle from the Pacific Northwest that feeds on the adelgid.

Esden said it will be many years before the state is certain that the beetle can be used to combat the spread of the adelgid, though he said initial finding are encouraging.

And the meeting, Esden said, is for people all over the region who are interested in learning more abut what can be done to slow down the spread of the hemlock woolly adelgid.

"We've known for sure that it was coming and now we are trying to slow the spread. We always though this was inevitable," he said. "We've dropped any thought about eradicating the adelgid."

Howard Weiss-Tisman can be reached at 802-254-2311, ext. 279, or hwtisman@reformer.com. You can follow him on Twitter @HowardReformer.