Ash pest found closer to Orange County

By George M. Walsh ALBANY — The invasive beetle that has destroyed tens of millions of ash trees over the past decade has been found east of the Hudson River for the first time, researchers said on April 18.

But the discovery of an emerald ash borer infestation in the Dutchess County village of Rhinecliff last month may signal a victory in the battle to stem the pest's spread: Foresters believe the colony was caught less than a year after it got established, a big step given that the beetle can go unnoticed for years.

Orange County is under quarantine for the ash borer. Researchers set out purple traps and stripped bark from trees last year, eventually mapping finds of beetle larvae in a 225-square-mile area running north from just below Kingston, bounded on the east by the river and parts of the Catskills in the west. Jeff Rider, a Department of Environmental Conservation supervising forester, said 28 "trap" trees on the east shore were also girdled — stripped of a band of bark — to attract any beetles that may have made it across.

The larval beetle tunnels under the bark, eventually destroying a tree without any sign until its foliage yellows and dies. The shiny green adults are only about half an inch long and tend to fly well above the ground, making them hard to spot.

"It's rare that infestations are found this early," said Nate Siegert, a U.S. Forest Service entomologist who has been working in Rhinecliff this month. He credited state foresters for taking steps that led to the discovery.

Ash trees, prized as a commercial hardwood and a feature in urban plantings, have been ravaged through much of the Midwest and into the mid-Atlantic and Northeast since the Chinese beetle was first discovered near Detroit in 2002. Borer infestations were found in western New York in 2009, but experts say the Hudson Valley colony could have started years before that, possibly after catching a ride across the state in a load of wood.

The main population has been spreading gradually at a pace of about two to three miles a year, but "satellite" colonies leapfrog ahead, mostly by hitchhiking in loads of logs or firewood.

New York became a leading edge for research and control efforts after a major infestation was discovered on the west shore of the Hudson in 2010, about 150 miles east of colonies discovered elsewhere in New York since 2009.

Rider said plans are being made to quarantine moving ash material in Dutchess County, but he thinks that may be limited to particular towns, not entire counties like across the river. People can be fined for moving firewood 50 miles beyond its origin, a regulation meant to thwart ash borers and other invasive pests.

Rider thinks the latest infestation involved adults that crossed the river during last summer's flying season.