The New York State Department of Environmental Conservation (DEC) and Cornell Cooperative Extension Suffolk County announced this week that emerald ash borer (EAB) has been confirmed for the first time in Eastern Long Island, on private property in the Town of Southold. Cornell Cooperative Extension confirmed larval specimens from infested trees earlier this month.
EAB is native to Asia and was first discovered in the U.S. in 2002 in southeastern Michigan. This invasive beetle infests and kills North American ash species (Fraxinus), including green, white, black, and blue ash. Although not a large component of Long Island's forest ecosystem, ash trees are often used as an amenity or shade tree in landscapes and along roadsides. Extensive losses from EAB reinforces the importance of diversity in New York’s urban forest canopy.
EAB infestation is difficult to detect during its early stages. Later signs of infestation include woodpecker activity and outer bark removed, numerous shoots produced on trunks or limbs, tree canopy yellowing or dieback, browning of leaves, and winding galleries in the inner bark. EAB has also been reported to attack fringe-trees (Chionanthus virginicus), a native shrub or small tree sometimes used in landscapes in New York State. After the pest is established in an area, heavily damaged trees may not recover.
The public is encouraged to send suspect samples and direct inquiries to the local Cooperative Extension Diagnostic Lab office in Suffolk County, and in Nassau County.
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. They may be present from late May through early September but are most common in June and July.
Although ash trees and wood are no longer subject to quarantine in the State, DEC invasive species regulations still 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 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.
Under Governor Cuomo’s leadership, the 2018-19 state budget included $13.3 million in the State’s Environmental Protection Fund targeted specifically for invasive species related initiatives.
For more information about emerald ash borer, visit DEC's website. Occurrences of EAB and other invasive species can be reported to the DEC’s Forest Health Diagnostic Laboratory by emailing photographs to email@example.com