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Please Check Your Hemlock Trees For Woolly Adelgid Infestation

Holden Arboretum has reported Hemlock Woolly Adelgids are now in our area. This is an invasive pest that is killing hemlock trees. It is important for everyone to check their hemlocks as many in our area are on private property.

The hemlock woolly adelgid is tiny, less than 1/16 inch long, and varies from dark reddish brown to purple black in color.  As it matures, it produces a covering of wool-like wax filaments to protect itself and its eggs from natural enemies and prevent them from drying out.  This “wool” is most conspicuous when the adelgid is mature and laying eggs.  Ovisacs can be readily observed from late fall to early summer on the underside of the outermost branch tips of hemlock trees.

The brochure from the US Department of Agriculture can be downloaded below.  It describes what to look for on your hemlocks. If you find you have an infestation, report it to:

Report Online: Invasive Species Report Form

Report By Phone:  ODNR 877-247-8733  or  ODA 614-728-6400

Download: Brochure on Woolly Adelgid In Eastern Hemlocks