ITHACA, N.Y. — Cornell University and state officials are banking on a beetle from the Pacific Northwest to stop an invasive insect from destroying upstate New York’s hemlock forests.

The first known hemlock woolly adelgid infestation in the Adirondacks was reported July 18 in a small number of trees on Prospect Mountain in Lake George, Warren County.

The tiny insect, from East Asia, was first detected in New York in 1985 and has already caused extensive damage in the southern Catskills and Finger Lakes region. However, 17 other states along the Appalachian Mountain range from Maine to Georgia have reported infestations.

Crews treated infected trees in Lake George with insecticide, but the most effective long-term control is a beetle that feeds on woolly adelgid eggs.

Cornell, with $1.2 million in state funding, recently opened a lab where beetles nicknamed “Larry” will be raised and released in large numbers to control the woolly adelgid. The beetle’s scientific name is Laricobius nigrinus.

“The threat is huge,” said Mark Whitmore, Cornell entomologist, who is running the lab. “Hemlock is an iconic, foundation species. It’s very important ecologically and aesthetically. I’ve heard the hemlock woolly adelgid described as the worst ecological disaster, after climate change.”

Two members of Congress from northern New York and Vermont have asked for federal funding to combat the problem, too. Earlier this month, Reps. Elise Stefanik, R-N.Y., and Peter Welch, D-Vt., wrote to Department of the Interior Secretary Ryan Zinke outlining their concerns and asking for technical and financial assistance.

“This invasive insect threatens the health of forests in our region and it is critical that we respond quickly to its arrival in our region,” said Stefanik, co-chairwoman of the Invasive Species Caucus.

“Vermont’s forests are a central part of our economy, environment and way of life,” Welch said. “It is critical that the Department of Interior work with state and local agencies and provide the necessary resources to prevent the spread of these species and maintain the health of our forests.”

Some estimates indicate that at least 10 percent of Adirondack forests are hemlock. But detecting the woolly adelgid won’t be easy as the 6 million-acre Adirondack Park has many vast, remote areas.

“Right now, that is the soft underbelly of the problem,” Whitmore said. “We don’t have enough people out there considering the size of the Adirondacks.”

Hemlocks are most abundant, numbering tens of thousands of acres, in the southeast part of the park including Lake George, which is reliant on tourism dollars. So potential impacts are both environmental and economic.

The woolly adelgid gets its name from the small white masses they produce, which look like wool and are attached to the underside of twigs near the base of needles. The insects feeds on young twigs, causing buds to die and needles to dry out and drop prematurely.

“Whether you are in the business of forestry or just have an appreciation and concern for the woods, we all need to know what to do about this insect and how to best protect our wooded areas,” said Dan Carusone of Warren County Cooperative Extension.

On Dec. 16, the New York State Department of Environmental Conservation put on a free workshop in Warren County to help people identify infestations. The program was led by Charlotte Malmborg, a colleague of Whitmore’s, who works for the New York State Hemlock Initiative at Cornell.

The Adirondack Mountain Club put on a similar program in September in Gloversville.

It’s unclear how the woolly adelgid spreads. It might be transported on birds’ feet or the wind.

Whitmore has been collecting and bringing home “Larry” beetles from the Pacific Northwest since 2009. The new lab marks the first attempt at raising them in New York, as the woolly adelgid threat increases.

The hope is that the beetles can be raised and released in sufficient quantities to counteract the havoc wreaked by woolly adelgids.

“It’s a numbers game,” he said.

Plans call for releasing the first lab-raised “Larry” beetles next fall. Until then, officials will buy time by continuing to treat isolated trees in the Adirondacks with insecticide. It’s a race against the clock because no one knows where the woolly adelgid will pop up next.

“They’ve already been spotted in Schenectady and Troy,” he said. “That’s way too close in my mind.”

A similar invasive insect, the balsam woolly adelgid, is of particular concern to Christmas tree growers, whose industry has an $8 million impact on New York state’s agricultural economy.

“It really wasn’t a problem until a few years ago,” he said. “Now it’s killing large numbers of trees.”

However, there are no plans to use natural controls to fight it because balsam aren’t as prevalent as hemlock and are only found in the wild at higher elevations, so the ecological threat isn’t as great. Farms that raise balsam and other types of fir such as Canaan and concolor, which the balsam woolly adelgid also attack, can treat infested trees with insecticide.

In an ideal world, Whitmore said he’d like to devote more time and effort combating this invasive pest as well. However, there isn’t enough funding and staff for such work, he said.

Paul Post is a freelance writer in eastern New York. He can be reached at paulpostPhoto courtesy of Ben Rand

The hemlock woolly adelgid.


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