Hemlock Woolly Adelgid Control Efforts

This past spring, we completed treatment of our eastern hemlocks to protect them from hemlock woolly adelgid (HWA).  The hemlock woolly adelgid is a small aphid-like invasive forest pest that lives, feeds, and reproduces exclusively on hemlocks. The insect kills the buds on infested branches, preventing new growth and eventually killing the tree. We treated 2,340 eastern hemlocks over the course of the project. Eventually retreatment may be necessary. In the meantime, we will measure the growth of treated trees using photographic analysis of canopy cover and monitoring for adelgid re-infestations.

We also are working with Cornell University in hopes of introducing two biocontrol insects into our environment. First, these insects go through a rigorous testing process that can take years to complete to determine that they will have little to no effect on native flora and fauna. A beetle (Laricobius nigrinus) and a silver fly (Leucopis argenticollis) from the Pacific Northwest are predators of the western hemlock woolly adelgid. Our hope is that these biocontrols and periodic treatments will save the unique eastern hemlock forest for the next generation to enjoy.

The hemlocks project was supported with funding from the New York State Conservation Partnership Program (NYSCPP) and New York’s Environmental Protection Fund. The NYSCPP is administered by the Land Trust Alliance, in coordination with the state Department of Environmental Conservation.

Posted in Stewardship & Land Management.