<Tr> <Th_colspan="2"> Binomial name </Th> </Tr> <Tr> <Td_colspan="2"> Adelges tsugae (Annand, 1928) </Td> </Tr> <P> Hemlock woolly adelgid (Adelges tsugae), or HWA, is member of the Sternorrhyncha suborder of the order Hemiptera and native to East Asia . It feeds by sucking sap from hemlock and spruce trees (Tsuga spp.; Picea spp .). In its native range, HWA is not a serious pest because populations are managed by natural predators and parasitoids and by host resistance . In eastern North America it is a destructive pest that threatens the eastern hemlock (Tsuga canadensis) and the Carolina hemlock (Tsuga caroliniana). HWA is also found in western North America, where it has likely been present for thousands of years . In western North America, it primarily attacks western hemlock Tsuga heterophylla and has only caused minor damage due to natural predators and host resistance . Accidentally introduced to North America from Japan, HWA was first found in the eastern United States near Richmond, Virginia, in 1951 . The pest is now found from northern Georgia to coastal Maine and southwestern Nova Scotia . As of 2015, 90% of the geographic range of eastern hemlock in North America has been affected by HWA . </P> <P> An adult individual body length is typically 0.8 mm, and is oval in shape . The tiny brown - colored insect has four thread - like stylets that are bundled together and function as a mouthpart . Three times the length of its body, the stylet bundle pierces the host plant's parenchymatic ray tissue to derive nutrition from stored reserves . It may also inject a toxin while feeding . The resulting desiccation causes the tree to lose needles and not produce new growth . Hemlocks stricken by HWA frequently become grayish - green rather than a healthy dark green . In the northern portion of the hemlock's range, death typically occurs 4 to 10 years after infestation . Trees that survive the direct effects of the infection are usually weakened and may die from secondary causes . </P>

Where did the hemlock wooly adelgid come from