Major Host:
 Hemlocks - especially deadly to eastern and Carolina hemlock
 
Key Features:
 Insects: Immature nymphs (crawlers) less than 1/16 inch long, dark reddish-brown to black.  As nymphs mature they develop a white waxy filamentous (wool-like) halo covering (late fall through early summer).  This covering eventually forms a cotton swab-like ovisac that harbors the eggs.
 
Damage: Feeding at the base of the needles by adelgids reduces stored starches in tree.  This feeding results in needle discoloration and eventual loss of needle.  Needle loss results in crown thinning and dieback which results in reduced vigor of the tree. Long-term infestations can kill trees.
 
Control/management:
 In a landscape situation, HWA can be treated using imidacloprid or other labeled systemic insecticides.  If detected please report the finding either to the Ohio Department of Agriculture, Ohio Division of Forestry or use the Great Lakes Early Detection Network smartphone app.
 

Resources

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• Hemlock Woolly Adelgid - USDA Forest Service
• Hemlock Woolly Adelgid Survey in Georgia - Georgia Forestry Commission
• Biological Control of Hemlock Woolly Adelgid - USDA Forest Service
• Hemlock Woolly Adelgid in Georgia -
• Proceedings: Hemlock Woolly Adelgid in the Eastern United States Symposium - USDA Forest Service
• Pest Alert - USDA Forest Service
• Hemlock Woolly Adelgid Action Team - Southern Appalachian Man and the Biosphere
• Pest Notes - The Nature Conservancy

Selected Images

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Invasive Listing Sources

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• Invasive Species of Concern in Georgia
• Maryland Invasive Species Council - Invasive Species of Concern in Maryland
• Michigan’s Invasive Species Watch List
• New Hampshire Prohibited Invasive Species
• New Jersey Invasive Species Strike Team 2017 Invasive Species List
• New York Regulated and Prohibited Invasive Species - Prohibited
• Nonnative Invasive Species in Southern Forest and Grassland Ecosystems
• Ontario’s Invading Species Awareness Program Tracked Species List
• South Carolina Plant Pest List
• Virginia Invasive Species Management Plan 2012
• West Virginia Invasive Species Strategic Plan and Volunteer Guidelines 2014
• Wisconsin's Invasive species rule – NR 40

References

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Common Name Reference: Bosik, J. J. Common Names of Insects and Related Organisms 1997. Lanham, MD: Entomological Society of America (ESA), 1997. 232 pp.

Scientific Name Reference: R.W. Poole and P. Gentili, Nomina Insecta Nearctica. 1996. Nomina insecta nearctica: a checklist of the insects of North America. Vol. 1-4. Rockville (MD): Entomological Information Services. Available at URL: http://www.nearctica.com/nomina/main.htm