The deadly invasive emerald ash borer -- a beetle that destroys ash trees -- has been discovered for the first time in New York state by Cornell researchers.

"The threat is extreme," said E. Richard Hoebeke, a senior extension associate in entomology at Cornell. "There is the potential for ash as we know it to be extirpated from the landscape."

The U.S. Department of Agriculture (USDA) Agricultural Research Service (ARS) in Washington, D.C., announced official identification of the beetle in New York state June 18 after receiving and examining specimens sent by Cornell researchers earlier this week.

The flying Asian beetle was discovered in ash trees near Randolph in Cattaraugus County in southwestern New York. The state has some 900 million ash trees, representing about 7 percent of all trees in the state, and all are at risk should this invasive pest become established.

The beetle -- which has metallic green wing covers and a coppery red or purple abdomen and is small enough to fit on a penny -- was first discovered in the United States in Michigan in 2002 and has since decimated more than 70 million ash trees in 13 Midwestern states and Pennsylvania, as well as many in southern Ontario in Canada. The beetle's larvae girdle under a tree's bark, killing the tree in one to three years.

On June 14, USDA-ARS entomologists John Vandenberg, a Cornell adjunct professor in entomology, and Michael Griggs, both based in Ithaca, were driving in New York on Route 17 to study the beetle in Michigan when they stopped to examine some damaged trees along the road and found the beetle, which appears to have been in the area for a few years. They contacted Hoebeke, who immediately drove to the area.

Hoebeke collected specimens and mailed them overnight to the USDA-ARS Systematic Entomology Laboratory in Washington, D.C., which then officially identified the emerald ash borer. State and federal agencies now will begin helicopter surveillance of the area and investigate strategies for controlling the pest.

"There's not a whole lot we'll be able to do about it," said Hoebeke. The standard practice of removing infested trees does not effectively stop the ash borers from spreading, he added. Officials plan to survey trees throughout the state and start an intensive effort to trap the ash borers in infested areas to assess the extent and longevity of the infestation. Information from this survey will help determine the response strategy, which could range from tree removals to ash product quarantines.

The beetle has most likely spread through the country via the transport of infested firewood, even though most states ban the interstate movement of untreated firewood.