The dreaded emerald ash borer has been detected in Westchester for the first time, the state Department of Environmental Conservation announced earlier this week. The invasive species of beetles, originally from Asia, was discovered in purple DEC traps just north of Peekskill.
It has also been found recently southeast of Binghamton, in Broome County, just outside the current state and federal quarantine zone. That zone encompasses all or part of 42 counties in central and western New York, including Putnam and Orange. Rockland is not yet on the quarantine maps, but the northeastern corner of the county is considered at risk.
To prevent humans from inadvertently transporting the beetles to new areas, quarantine regulations prohibit the movement of untreated firewood more than 50 miles from its source or origin. Infested wood can’t be moved anywhere. On their own, the beetles will only move about a mile per year.
So far the flat-headed, emerald-green beetle that’s smaller than a dime has been detected in 24 counties in the state. To put this in perspective, New York has an estimated 900 million ash trees, making up about 7 percent of the state’s trees. Most ash trees in New York are either green ash or white ash; all species of ash are susceptible to the borer.
Urban and suburban communities face particular risks, the DEC said, because ash is a common street and park tree. In urban areas, many communities planted ash trees to replace American elms that were devastated by Dutch elm disease in the 1950s and ’60s.
Green ash is also a common ornamental tree in suburban yards. New York ash is used in many products, including Louisville Slugger baseball bats.
Most of the infested areas in the state are small and localized so far, with more than 98 percent of New York’s forests and communities not yet infested.
It’s the larvae of the beetle that causes the damage, feeding on the ash tree just under the bark.
The resulting tunnels they create disrupt he tree’s ability to take in water and nutrients. Most trees die within one to four years of being infested.
The ash borer, which has a metallic appearance, was first detected in New York in the town of Randolph, Cattaraugus County, in June 2009. The beetles were first discovered in North America in 2002, when they were found in Michigan and Ontario, Canada. Since then, they have killed millions of ash trees as they make their way east.
The Westchester trap that detected the EAB beetle is part of the DEC’s Slow Ash Mortality (SLAM) strategy, which aims to slow the spread of the ash borer and remove infested trees. The strategy also includes researching insecticides and organisms that kill the pest and monitoring areas where the beetle has not been seen yet, according to a DEC news release.
Check your trees now
The DEC is urging residents and municipalities to check their ash trees and look for signs of infestation. Both homeowners and municipalities can contact the nearest DEC Forestry Office for technical assistance and management recommendations.
Management options include removing stressed ash trees that may attract the beetle and treating healthy trees with insecticides.
The regional office for the Lower Hudson Valley (Westchester, Rockland, Putnam, Dutchess, Orange, Sullivan and Ulster counties) is at
21 South Putt Corners Road in New Paltz, 845-256-3000.
To report signs of the emerald ash borers, or ash trees showing symptoms of infestation, call the DEC’s emerald ash borer hot line at 866-640-0652 or visit http://www.dec.ny.gov/animals/72136.html
What to look for
Adult beetles leave distinctive D-shaped exit holes in the outer bark of the tree’s branches and trunk. Other signs of infestation from the ash borer include basal sprouting, a burst of new green growth at the base of the tree; tree canopy dieback; vertical splits in the bark with serpentine galleries, or tunnels, underneath; and D-shaped exit holes in the bark. You can also look for woodpecker damage because the birds find the larvae quite tasty.
Adults, which live just three to four weeks, are active in late May to mid-August, feeding heavily on the foliage of the ash trees. The females lay eggs on or just under the bark.
When the larvae hatch, they bore through the bark and spend the winter there, making aggressive galleries under the bark and causing canopy dieback.
After the larvae pupate, they emerge as adult beetles through D-shaped exit holes in the bark of the ash tree. Most have a one-year life cycle.