Tuesday, January 26, 2021

DEC gives update on fight against hemlock wooly adelgid

Hemlock with HWA egg masses_Connecticut Agricultural Experiment StationThe New York State Department of Environmental Conservation (DEC) and partners issued an update about ongoing efforts to limit the spread of the invasive pest Hemlock Wooly Adelgid (HWA) on Forest Preserve lands in Washington County as part of an ongoing, multi-year initiative. DEC confirmed the HWA infestation in August 2020, and began treatment in October on affected hemlock trees in the Glen Island Campground on the shores of Lake George.

Treatment began Oct. 6, 2020 along the shorelines of Lake George and was conducted over a four-week period by DEC staff. DEC prioritized the infestation at Paradise Bay due to the site’s size and levels of infestation. Crews treated 2,374 trees with insecticide on 138 acres of Paradise Bay and injected insecticides directly into the trunks of 80 trees close to sensitive areas. In addition, the New York State Hemlock Initiative released 620 Laricobius beetles, a biological control for HWA, in the treatment area to feed on HWA.

Since the initial finding of HWA at Glen Island, DEC and its partners continued to survey for the insect in surrounding areas. These surveys led to new findings of HWA at Shelving Rock; Buck Mountain Trail Head; Dome Island, private property along the southern shore of Lake George in Queensbury; and Moreau Lake State Park. To address the infestation, DEC is planning consecutive annual treatments to treat many of the trees in the infested areas, as well as additional strategies. Spring treatments at Glen Island Campground will begin after ground thaw when trees begin to transpire and will take up insecticides and end before the campground opens for the season. Treatment dates and strategies are being determined and will help limit the spread of HWA and protect accessible priority hemlock resources that provide habitat and water quality protections, opportunities for recreation, and aesthetic benefits.

DEC and its partners conducted public outreach about ongoing actions to limit the spread and new findings of HWA, including direct outreach to stakeholders and traditional and social media outreach. In addition, the Capital Region Partnership for Regional Invasive Species Management’s (PRISMs) set up the HWA mobile sign in the parking lot of the popular Million Dollar Beach and distributed informational brochures at trailheads in and around Lake George and at the Northway Exit 18 rest area.

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 wooly 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 Wooly Adelgid

A tiny insect from East Asia first discovered in New York in 1985, HWA 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 their deep shade helps to keep stream temperatures cool. They also 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 2020, 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, including identification, control techniques, and reporting possible infestations can be found at Cornell’s New York State Hemlock Initiative [email protected] or call DEC’s toll-free Forest Pest Information Line at 1-866-640-0652 to report possible infestations.

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NYS DEC

Information attributed to NYSDEC is taken from press releases and news announcements from New York State's Department of Environmental Conservation.




One Response

  1. Vanessa Banti Vanessa says:

    Thank you DEC! I was just talking about HWA with my local arborist because I discovered an infestation at our local park last week :(:(. (I’m in eastern Massachusetts.) His prognosis for the trees in question was grim.

    However, we haven’t had a winter in a long time that is cold enough to kill them. Whereas happily I noticed that it’s gonna get down to -3F over the weekend in Lake George, which should help, right? Further north it will cross the -5 threshold that I have read is critical.

    For now, this will be useful but this is another problem that the changing climate is going to make quite tough to handle :(:(

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