- 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...
