ROTTERDAM, N.Y. — A popular hiking area in New York with steep gorges and numerous waterfalls is closing down for pesticide treatments to fight an insect that damages hemlock trees.

The Department of Environmental Conservation says the Plotter Kill Preserve in Schenectady County will be closed Monday through Wednesday. If it rains, the pesticide application will be postponed to Nov. 1.

The pest is the hemlock wooly adelgid, a non-native species that can cause significant harm to a forest. The state agency says it has recently been discovered at the Plotter Kill Preserve in Rotterdam and the Indian Kill Preserve in the town of Glenville.

Damage from the insect has killed many hemlocks throughout the Appalachian and southern Catskill mountains.

A minor infestation was recently treated in Warren County in the southeast Adirondacks.