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Japanese Knotweed

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Japanese knotweed
Scientific Name:
Fallopia japonica (Houtt.) Ronse Decr. (ITIS)
Synonym:
Polygonum cuspidatum Siebold & Zucc.; Reynoutria japonica Houtt.
Common Name:
Japanese knotweed, fleeceflower, Mexican bamboo, huzhang
Photo:
Japanese knotweed, foliage - Photo by Jack Ranney; University of Tennessee
Native To:
Asia (Stone 2010)
Date of U.S. Introduction:
Late 1800s (Stone 2010)
Means of Introduction:
Introduced as an ornamental (Stone 2010)
Impact:
Crowds out native species (Stone 2010)

Distribution/Maps/Survey Status

Images

Videos

Selected Resources

The section below contains selected highly relevant resources for this species, organized by source. To view all related content for this species, click on "View all resources for species" in the top left of this page.

Council or Task Force

Ohio Invasive Plants Council.
See also: Invasive Plants of Ohio for worst invasive plant species identified in Ohio's natural areas
Washington State Recreation and Conservation Office. Washington Invasive Species Council.

Partnership

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)
IUCN. Species Survival Commission. Invasive Species Specialist Group.
Ontario's Invading Species Awareness Program (Canada).
University of Georgia. Center for Invasive Species and Ecosystem Health.
University of Georgia. Center for Invasive Species and Ecosystem Health.
CABI Bioscience.

New York Invasive Species Clearinghouse.

Great Britain Non-Native Species Secretariat.

Federal Government

USDA. FS. Rocky Mountain Research 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

Cornwall County Council (United Kingdom).

Australian Government. Department of the Environment and Energy.

State and Local Government

Washington State Noxious Weed Control Board.
California Department of Food and Agriculture.
See also: Included on California's noxious weed list; see Encycloweedia: Program Details for additional resources
New Hampshire Department of Agriculture, Markets, and Food. Division of Plant Industry.
See also: New Hampshire's Prohibited Invasive Plant Fact Sheets for additional invasive trees, shrubs, vines, and herbaceous plants
Missouri Department of Conservation.

Indiana Department of Natural Resources. Invasive Plant Species Assessment Working Group.

See also: Species Assessments and Invasive Species for exotic animal and plant pests invading Indiana, causing economic and visual damage
Pennsylvania Department of Conservation and Natural Resources.
See also: Invasive Plant Fact Sheets for plant species (trees, shrubs, vines, herbs and aquatic plants) that have impacted the state's natural lands
Michigan Department of Natural Resource; Michigan State University Extension. Michigan Natural Features Inventory.
See also: Best Control Practice Guides for more guides

Wisconsin Department of Natural Resources.

King County Department of Natural Resources (Washington). Water and Land Resources Division.
Colorado Department of Agriculture. Conservation Services Division. Noxious Weed Program.

Academic

Pennsylvania State University. Pennsylvania Sea Grant.
See also: Aquatic Invasive Species: Resources for additional species information
Columbia University. Center for Environmental Research and Conservation.
Pennsylvania State University. Cooperative Extension.
North Carolina State University. Cooperative Extension. Going Native: Urban Landscaping for Wildlife with Native Plants.
Purdue University (Indiana). Extension.
University of Maine Cooperative Extension.
See also: Maine Invasive Plants & Entire Series for entire series of 22 fact sheets and invasive plants brochure (available in HTML/PDF or for purchase)
Ohio State University. Ohio Agricultural Research and Development Center.

Citations