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Quackgrass, plants in Alaska - Photo by Elizabeth Bella; USDA, Forest Service
Scientific Name: 

Elymus repens (L.) Gould subsp. repens (ITIS)


Agropyron firmum J. Presl, Agropyron repens (L.) P. Beauv., Elytrigia repens (L.) Desv. ex Nevski, Triticum firmum (J. Presl) Link, Triticum repens L. (GRIN)

Common Name: 

Quackgrass, medusa's head, Quackgrass rye, Quackgrass grass

Native To: 

Eurasia (Klein 2011)

Date of U.S. Introduction: 

1600s (Klein 2011)

Means of Introduction: 

Accidental, probably as a seed contaminant (Klein 2011; Werner and Rioux 1977)


Crowds out native species and cultivated crops (Klein 2011)

Distribution / Maps / Survey Status

University of Georgia. Center for Invasive Species and Ecosystem Health.
Provides state, county, point and GIS data. Maps can be downloaded and shared.


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


Google. Google. YouTube; Ag PhD: Information for Agriculture.

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 Quackgrass.

University of Alaska - Anchorage. Alaska Center for Conservation Science.
See also: Non-Native Plant Species List for additional factsheets (species biographies) and species risk assessment reports of non-native species present in Alaska and also non-native species currently not recorded in Alaska (potential invasives)

USDA. APHIS. PPQ. Center for Plant Health Science and Technology; California Department of Food and Agriculture.

University of Georgia. Center for Invasive Species and Ecosystem Health.
Texas State University System. Texas Invasive Species Institute.
Federal Government
USDA. FS. Rocky Mountain Station. Fire Sciences Laboratory.

Smithsonian Institution. Smithsonian Environmental Research Center. Marine Invasions Research Lab.

USDA. NRCS. National Plant Data Center.

USDA. ARS. National Genetic Resources Program. GRIN-Global.

International Government
Ontario Ministry of Agriculture, Food, and Rural Affairs (Canada).
State and Local Government

Thurston County Public Health and Social Services (Washington). Environmental Health.

See also: IPM for Homeowners & Land Managers for more species
California Department of Food and Agriculture.
See also: Included on California's noxious weed list; see Encycloweedia: Program Details for additional resources

Colorado Department of Agriculture. Conservation Services Division. Noxious Weed Program.

Maine Department of Agriculture, Conservation and Forestry.

See also: Weeds - Quackgrass for more species resources

Pennsylvania State University. Cooperative Extension.

Ohio State University. Ohio Agricultural Research and Development Center.

University of Maine. Sustainable Agriculture Program.
See also: For Farmers for more resources