Hemlock Woolly Adelgid - Home and Garden IPM from Cooperative Extension - University of Maine Cooperative Extension

Hemlock Woolly Adelgid (an invasive pest) The Hemlock Woolly Adelgid (Adelges tsugae), often abbreviated as HWA, is a very small (1/32″ long) invasive Hemipteran (‘true bug’) that feeds on sap that it sucks from hemlock trees (Tsuga spp.). It was accidentally introduced to western North America from its native Asia in 1924, and