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For Release: Monday, November 16, 2020

DEC Announces Update on Lake George Hemlock Woolly Adelgid Treatment

Collaborative Efforts Underway to Help Prevent HWA's Spread in Region

The New York State Department of Environmental Conservation (DEC) and partners have completed this year's treatment to control and prevent the spread of Hemlock Woolly Adelgid (HWA) on Forest Preserve lands in Washington County, as part of an ongoing, multi-year effort. DEC confirmed the HWA infestation in August. The affected hemlock trees were located in the Glen Island Campground on the shore of Lake George, along the shoreline of Shelving Rock Special Management Area, at the Buck Mountain Trailhead, and on Dome Island.

DEC footage taken during the fall treatment efforts are available here:

After the initial finding of HWA, DEC, Cornell's New York State Hemlock Initiative, the Adirondack Park Invasive Plant Program (APIPP), and Lake George Land Conservancy staff spent approximately 100 working days surveying and delineating the infestation to prepare for treatment. Additional survey and treatment will be required in future years to effectively manage this infestation.

Treatment began Oct. 6, and was conducted over a three-week time period by DEC's Division of Lands and Forests. DEC crews from across the state were supported by partners from Capital District/Mohawk Partnership for Regional Invasive Species Management and APIPP. In total, 275 working days were spent during the treatment period covering 138 high priority acres. Within the 138 acres approximately 2,500 hemlock trees were treated to kill any present HWA and protect from any future infestations. Trees were treated with both imidacloprid (long lasting) and dinotefuran (quick acting) pesticides and were primarily treated with a targeted basal bark spray application to limit any impacts to non-target species. Additionally, 80 trees in sensitive locations were treated by a direct injection method to further reduce impacts on non-target species and to the watershed. As part of a biological control effort to combat HWA within the infestation area, DEC partners at the New York State Hemlock Initiative released 620 Laricobius beetles, which feed on adelgids.

Early detection and rapid response to invasive pests is central to protecting New York's natural resources. DEC and its partners' efforts to further prevent the spread of HWA are critical to protecting the hemlock forests in the Lake George watershed and greater Adirondack Park.

Signs of HWA on hemlock trees include white woolly masses (ovisacs) about one-quarter the size of a cotton swab on the underside of branches at the base of needles, gray-tinted foliage, and needle loss. DEC is asking the public to report signs of HWA:

About Hemlock Woolly Adelgid

HWA, a tiny insect from East Asia first discovered in New York in 1985, attacks forest and ornamental hemlock trees. It feeds on young twigs, causing needles to dry out and drop prematurely and cause branch dieback. Hemlock decline and mortality typically occur within four to 10 years of infestation in the insect's northern range. Damage from the insect has led to widespread hemlock mortality throughout the Appalachian Mountains and the southern Catskill Mountains with considerable ecological damage, as well as economic and aesthetic losses. HWA infestations can be most noticeably detected by the small, white, woolly masses produced by insects attached to the underside of the twig, near the base of the needles.

Eastern hemlock trees, which comprise approximately 10 percent of the Adirondack forest, are among the oldest trees in New York with some reaching ages of more than 700 years. These trees typically occupy steep, shaded, north-facing slopes and stream banks where few other trees are successful. The trees help maintain erosion control and water quality, and the hemlock's shade cool waters provide critical habitat for many of New York's freshwater fish, including native brook trout.

To support New York State's overall efforts to combat invasive species, the 2019 State Budget included $13.3 million in the Environmental Protection Fund targeted specifically to prevent and control invasive species. This funding is providing critical support for prevention, eradication, research, and biological control efforts through programs like the New York State Hemlock Initiative and PRISM that protect against threats to New York's biodiversity, economy, and human health.

In September, DEC announced partnerships with the New York Invasive Species Research Institute (NYISRI) and Cornell University to develop and support projects and research to help limit the spread of invasive species. Supported by the State's Environmental Protection Fund with $3.5 million, the NYISRI five-year term agreement includes $2.5 million for invasive species projects; the agreement with Cornell University includes a two-year term with $1 million to support the New York Hemlock Initiative. This work provides a critical service by developing methods to conserve hemlock, including the growth and release of several biological control agents and other fundamental survey, research, and trend analyses.

More information on HWA (leaves DEC website), including identification, control techniques, and reporting possible infestations can be found at Cornell's New York State Hemlock Initiative webpage or call DEC's toll-free Forest Pest Information Line at 1-866-640-0652 to report possible infestations.

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