Chinese wasps deployed to fight off spread of invasive ash borer

Section: Main,  Page: A3

Date: Friday, July 22, 2011

CEMENTON -- In woods off Route 9W in the tiny hamlet of Cementon, Greene County, tiny Chinese wasps will take flight next month as America's allies against a tide of ravenous beetles that have devoured ash trees by the millions.

If successful, the deliberate release of the wasps could blunt the spread of the emerald ash borer, which is now in New York, more than a dozen other states and Canada since arriving in the U.S. a decade ago.

Last week, the tiny, metallic-green beetles invaded the U.S. Military Academy in West Point, Orange County. The borers were found in a purple box trap, one of thousands that DEC has put across the state to track the beetles' advance.

Last summer, they were found in Greene and Ulster counties.

The beetles first arrived in western New York, around Randolph in Cattaraugus County, in summer 2009.

Orange County has been added to a state-imposed quarantine zone that restricts movement of ash tree materials to prevent spread of the pest.

This summer, New York is among eight states where officials from the U.S. Agriculture Department will release wasps, which are native to Chinese forest home of the borer and feed on its larval form.

Three different varieties of wasps, reared in a federal lab in Michigan, have been studied to be sure they won't create environmental problems by attacking something else unexpectedly, said John Vandenberg, a research entomologist with the U.S. Agriculture Department Research Service.

Sometime next month, Vandenberg will bring boxes of several hundred wasps to four locations in Greene and Ulster Counties, including sites near Saugerties, Glasgow, Lake Katrine and Bristol Beach State Park. After those initial releases, he'll unleash the wasps in Cattaraugus County.

The hope, he said Thursday, is wasps will be drawn to ash trees that have been deliberately stripped of some bark to become attractive targets for attack by the borers, which lay eggs inside ash trees.

"We want to up the odds for the wasps to have easy hunting," said Vandenberg.

The borer larvae emerge in the spring and eat their way through a tree. Millions of trees have been destroyed in infested states since the beetle spread out from Detroit, where the borer arrived in 2002 -- likely inside infested shipping containers. The borer has no natural enemies in the U.S.

Reach Brian Nearing at 454-5094 or bnearing@timesunion.com.