woolly adelgid

Hemlock woolly adelgid (Adelges tsugae), commonly abbreviated as HWA is a true bug native to East Asia that feeds by sucking sap from hemlock trees (Tsuga sp.). In eastern North America it is a destructive pest that poses a major threat to the Canadian hemlock (Tsuga canadensis) and the Carolina hemlock (Tsuga caroliniana). The former extends north of the current range of the adelgid, but there are fears that it could spread to these areas. Accidentally introduced from Asia in the 1920s, HWA has now been established in eleven eastern states from Georgia[1] to Massachusetts, causing widespread mortality of hemlock trees.
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woolly adelgid
n : an insect that feeds on hemlocks; its egg sacs are small fuzzy white balls like artificial snow on a christmas tree

Noun
1. an insect that feeds on hemlocks; its egg sacs are small fuzzy white balls like artificial snow on a Christmas tree
(hypernym) adelgid