ALBANY -- An invasive beetle that has killed tens of millions of ash trees in the Midwest and Canada has been found for the first time in New York.

The state Department of Environmental Conservation says emerald ash borers were discovered this week in Cattaraugus County, in the southwestern corner of the state. About 30 trees appear to be infested.

Carol Ash, commissioner of the state parks department, says the pests may cause significant ecological and economic harm if not contained. State scientists are studying the infestation to determine what action to take.

In 2008, New York banned untreated firewood from entering the state to deter the introduction of emerald ash borers and other invasive species.