Hemlock

Hemlock Wooly Adelgid (Adelges tsugae Annand) has become a problem in eastern Pennsylvania forests.

Penn State Department of Entomology fact sheet: "The most obvious sign of a hemlock woolly adelgid infestation is the copious masses of white filaments of wax produced by females. These "cottony" masses normally persist throughout the season and into the following year, even after the insects are dead”. http://www.ento.psu.edu/extension/factsheets/hemlockwoolly.htm

Our 35-year-old hemlocks are about 70 feet tall. (see picture below) That’s too large for me to spray with insecticidal soap. I’m keeping an eye on them. Hopefully, they will last another 35 years.

Here are a two sites that illustrate the difficulty of control.

USDA Forest Service “An Exotic Pest Threat to Eastern Hemlock: An Initiative for Management of Hemlock Woolly Adelgid” http://www.na.fs.fed.us/fhp/hwa/pub/hwa_mgt_plan.pdf

Save Our Hemlocks Action Team http://www.saveourhemlocks.org/controls/my_prop.shtml