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Hemlock Woolly Adelgid

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Hemlock Woolly Adelgid
Hemlock Woolly Adelgid, Adult with wax removed - Michael Montgomery USDA, Forest Service
Scientific Name: 
Adelges tsugae (Annand) (Annand 1928)
Common Name: 
Hemlock Woolly Adelgid (HWA)
Native To: 
Date of U.S. Introduction: 
Discovered on the West Coast in the 1920s, but it is disputed whether this was an introduced or native population; an introduced population was discovered on the East Coast in the 1950s (Havill et al. 2006; Orwig et al. 2003)
Means of Introduction: 
Impact: 
Destroys Eastern hemlock trees (Tsuga canadensis) (Orwig et al. 2003)

Spotlights

USDA. FS. Southern Research Station. CompassLive.

Laricobius nigrinus is a small beetle that eats an even smaller bug – the hemlock woolly adelgid, or HWA. Since 2003, Laricobius has been used to help control HWA. But the beetle, which is native to western North America, is only active during the fall, winter and early spring. Recently, USDA Forest Service research entomologist Bud Mayfield and his colleagues, including students and prominent researchers, published the results of a six-year collaboration on Laricobius as biocontrol.

Silvicultural recommendations for managing HWA are still in development. But when they are available, Mayfield and his colleagues plan to update their resource manager’s guide. They wrote the guide for managers who want to use an integrated pest management strategy to control hemlock woolly adelgids.

USDA. FS. Southern Research Station. CompassLive.

Forest Service scientists have published a guide synthesizing best practices for controlling these tiny bugs. It promotes a strategy of combining insecticide use with adelgid-eating insects.

Distribution / Maps / Survey Status

USDA. FS. Northern Research Station.

Select the non-indigenous forest pest to view maps depicting state and county distribution. Produced by: USDA, FS, Forest Health Protection, and its partners.

University of Georgia. Center for Invasive Species and Ecosystem Health.
Provides state, county, point and GIS data. Maps can be downloaded and shared.
USDA. FS. Northeastern Area State and Private Forestry.
Provides distribution maps and predicted future range expansion.
USDA. APHIS. Cooperative Agricultural Pest Survey. National Agricultural Pest Information System.

Quarantine

Vermont Department of Forests, Parks and Recreation. Forestry Division.

Images

University of Georgia. Center for Invasive Species and Ecosystem Health.

Videos

Google. YouTube; New York Department of Environmental Conservation.

Selected Resources

The section below contains highly relevant resources for this species, organized by source. Or, to display all related content view all resources for Hemlock Woolly Adelgid.

Partnership

USDA. Forest Service; Southern Regional Extension Forestry. Forest Health Program.

See also: Hemlock Woolly Adelgid for more resources

National Plant Diagnostic Network.

You can become a more effective First Detector by familiarizing yourself with invasive target pests and pathogens known to exist in the U.S. If you think you have encountered one of the species or disease complexes listed, report its presence.

Nature Conservancy. Don't Move Firewood.
IUCN. Species Survival Commission. Invasive Species Specialist Group.

New York Invasive Species Clearinghouse.

Texas State University System. Texas Invasive Species Institute.
Federal Government
State and Local Government

Wisconsin Department of Natural Resources.

Pennsylvania Department of Conservation and Natural Resources.

Maryland Department of Agriculture.

Maine Department of Conservation. Maine Forest Service. Forest Health and Monitoring Division.

Ohio Department of Agriculture. Plant Health.

New York Department of Environmental Conservation.
Academic

Alabama Cooperative Extension System.

Rutgers University. New Jersey Agricultural Experiment Station.

University of Minnesota.
IPM of Midwest Landscapes is available for educating growers, landscapers, managers, and consumers in the principles of IPM and its application to managing the over 150 common insect species in Midwest landscapes.
Cornell University. Cooperative Extension of Suffolk County. Horticulture Diagnostic Laboratory.
See also: Tree and Shrub Insect Pests for more fact sheets.

University of Maryland Extension.

Pennsylvania State University. Cooperative Extension.

Columbia University. Center for Environmental Research and Conservation.

Cornell University. Forest Health and Invasive Non-native Forest Pests.

Citations