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For Release: Friday, April 26, 2019

DEC to Begin Treatment for Invasive Pest Hemlock Woolly Adelgid at Schenectady County Nature Preserve


The New York State Department of Environmental Conservation (DEC) announced today that DEC and the Schenectady County Environmental Advisory Council's (SCEAC) Invasive Species Committee will begin pesticide treatments next week at the Plotter Kill preserve to combat the spread of the invasive pest hemlock woolly adelgid (HWA).

HWA is a non-native tree pest that can pose significant harm to the forest ecosystem and has been discovered at both the Plotter Kill preserve in the town of Rotterdam and the Indian Kill preserve in the town of Glenville.

In November of 2017, 250 hemlock trees were treated in the Plotter Kill preserve after they were found to be infested with HWA. A similar number of additional trees will be included in the upcoming treatment program.

Weather permitting, certified pesticide applicators will treat hemlock trees in the Plotter Kill preserve from April 29 through May 3. While the actual treatment should only take one day, a week-long window has been set aside in case of inclement weather. Signs will be posted at preserve parking lots and public access will be temporarily restricted during the treatments.

Certified pesticide applicators will apply a mixture of two systemic pesticides, dinotefuran and imidacloprid, to the lower portion of the hemlock tree trunk to provide both immediate and long-term protection. These pesticides have not been shown to have adverse health or environmental impacts at the levels used with this treatment program. The treatment program is a collaboration between DEC's Division of Lands and Forests, the Capital-Mohawk Partnership for Regional Invasive Species Management (PRISM), and municipal and county officials.

Schenectady County recently approved a resolution accepting a Long-Term Hemlock Management Plan that was developed by the SCEAC's Invasive Species Committee. The treatment program is part of the overall strategy detailed in the plan to preserve the county's hemlock resources and to slow the spread of HWA to other areas of the state, such as the Adirondacks.

Hemlocks are an important part of natural ecosystems where they grow along streams and steep slopes and help to provide erosion control along streambanks and waterbodies, as well as provide shade to keep water cool enough to support a healthy aquatic environment. Left untreated, HWA normally kills trees within four to 10 years in the insect's northern range. Damage from the insect has led to widespread hemlock mortality throughout the Appalachian and southern Catskill mountains, with considerable ecological damage, as well as economic and aesthetic losses.

To slow down and limit the spread of HWA, DEC and SCEAC's Invasive Species Committee are working together to protect hemlocks in the two county preserves. The use of insecticides is necessary to preserve the local hemlocks until DEC can successfully implement a long-term control plan that will entail the use of predators for biological control of the pest.

For more information about the project, please contact DEC's forest health information line at 1-866-640-0652, email foresthealth@dec.ny.gov, or visit DEC's website.

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