Wooly Adelgid

Hemlock woolly adelgid are insects which feed on hemlock and spruce trees and shrubs. They are most destructive to eastern and Carolina hemlock. The symptoms include the yellowing and dropping of needles, followed by the drying of branches and thinning of the crown. The woolly adelgids are less than 1/16" in size and may vary in color from brownish-red to purplish-black. The crawlers hatch and the first instar nymphs feed on stored starch at the base of the needles through piercing, sucking mouth parts.  Activity by hemlock woolly adelgid is normally detected by the white, fluffy, wool ovisacs  on the underside of the outermost branch tips. 

Hemlock woolly adelgid can be controlled by insecticidal soaps, horticultural oil, pesticide spraying, soil injections or basal trunk spraying. The time of year, size of trees and severity of infestation are all considered when choosing the appropriate method of treatment.

Contact Plant Health Solutions for proper diagnosis and to develop a treatment plan. 

Pete discovered that my hemlocks were infested with wooly adelgid and eliminated them, which most likely saved the trees. He is very vigilant and proactive regarding deer tick reduction. I learned a lot from him about this and definitely benefited from his knowledge.

-Wendy M. (Doylestown, Bucks County)

  • Wooly Adelgid
  • Wooly Adelgid