The New York State Department of Environmental Conservation (DEC) has announced that emerald ash borer (EAB) has been confirmed in two locations in Jefferson County. A sample collected from a tree in the city of Watertown on South Massey Street was positively identified by the Cornell University Insect Diagnostic Lab.

The sample was taken in cooperation with the City of Watertown Planning Department and Department of Public Works. A second location was confirmed in the village of Clayton.

Ash trees are a component of some Adirondack forest ecosystems and ash trees have often been used as shade trees in landscaping, including as street trees.  The first infestation in New York State was discovered in Cattaraugus County in 2009, and the invasive species was discovered in the Hudson River Valley in 2010.

Emerald Ash Borer was confirmed in Saratoga County at Ballston Lake in June of 2016, in Oneida County at Rome a month later. In 2017, EAB was found in St. Lawrence County, near Hammond, and at Massena (a large infestation) and on St. Regis Tribal Land, both in Franklin County.  While Jefferson County is not part of the Adirondack Park, the Black River (where much ash grows) flows into the County from the Park’s southwest and Lewis, Warren Clinton Counties can be expected to be confirmed as infected next.

EAB larvae feed in the cambium layer just below the bark, disrupting the transport of water and nutrients into the crown and killing the tree often within a few years. Emerging adult beetles leave distinctive 1/8-inch, D-shaped exit holes in the outer bark of the branches and the trunk. Adults are roughly 3/8 to 5/8 inches long with metallic green wing covers and a coppery red or purple abdomen. These insects may be present from late May through early September, but are most common in June and July.

A full blown infestation of EAB is expected to wipe out some 900 million ash trees in New York State over about 15 years.  Although ash trees and wood are no longer subject to quarantine in New York State, DEC invasive species regulations prohibit most movement of EAB and other prohibited species, with some exemptions for identification and disposal.

DEC firewood regulations regulate the movement of untreated firewood of all wood species to prevent the spread of invasive tree pests, including EAB. DEC recommends that wood from ash trees that have been infested and/or killed by EAB be left or utilized on site or chipped to less than one inch in at least two dimensions to prevent further spread.

The 2019 State Budget included a total of $13.3 million in the Environmental Protection Fund targeted specifically to prevent and control invasive species.

For more information on how to identify emerald ash borer, and treatment options, visit DEC’s website. Occurrences of any invasive species can be reported to the DEC’s Forest Health Diagnostic Laboratory by emailing photographs to foresthealth@dec.ny.gov.

Municipalities and landowners looking for advice on dealing with EAB may contact regional DEC Private Lands Staff.

Photo of emerald ash borer courtesy DEC.