hemlock woolly adelgid

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Pennsylvania has 58 separate species of non-native forest pests threatening trees and plant life, according to a new study out Tuesday in the journal Ecological Applications.

“That’s second only to New York state in terms of the number of pests,” said lead author Gary Lovett, senior scientist at the Cary Institute of Ecosystem Studies in upstate New York.

Hemlock Killer Makes Its Way to Western Pennsylvania

Apr 29, 2013

A small killer is making its way through Pennsylvania, leaving dead hemlock trees in its wake.

According to the Pennsylvania Department of Conservation and Natural Resources (DCNR), the hemlock woolly adelgid has been detected in Cook Forest State Park in Clarion County and Clear Creek State Park in Jefferson County.

The hemlock woolly adelgid (HWA) is an invasive beetle-like insect originating from southern Japan. The adelgid multiplies at the base of a tree and moves upward attaching itself to the underside of branches.