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Hemlock woolly adelgid: a threat to eastern forests

Informally Refereed

Abstract

The hemlock woolly adelgid (HWA) (Adelges tsugae Annand) is a destructive, non-native pest of forest and ornamental hemlock trees in eastern North America. It was first collected in the eastern United States in 1951 in Richmond, Virginia, arriving sometime earlier directly from southern Japan, probably on live plant material. Other than its new association with eastern and Carolina hemlock, HWA has been historically associated with hemlock species in western North America and Asia. The geographic range of eastern hemlock extends from the Canadian Maritime Provinces, west to the Great Lakes region, and as far south as northern Georgia and Alabama, with many separated populations to the south and west of its main range.

Citation

Havill, Nathan P.; Vieira, Ligia C.; Salom, Scott M. 2014. Hemlock woolly adelgid: a threat to eastern forests. National Woodlands. 37(2): 14-15.
https://www.fs.usda.gov/research/treesearch/46789