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Japanese Knotweed

Scientific Name

Fallopia japonica (Houtt.) Ronse Decr. (ITIS)

Common Name

Japanese knotweed, fleeceflower, Mexican bamboo, huzhang

Synonym

Polygonum cuspidatum Siebold & Zucc.; Reynoutria japonica Houtt.

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)

Japanese knotweed
Image use policy

Japanese knotweed, foliage

Credit

Photo by Jack Ranney; University of Tennessee

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Distribution / Maps / Survey Status

Videos

Selected Resources

The section below contains highly relevant resources for this species, organized by source.

Council or Task Force
Partnership
Federal Government
International Government
State and Local Government
Academic
Professional
Citations