Bohemian knotweed, Hybrid Japanese knotweed
(Reynoutria x bohemica Chrtek & Chrtková)

Overview

Appearance

Fallopia x bohemica is a perennial that can grow from 6-12 ft. (1.8-3.7 m) tall.

Foliage

Stems are usually erect, clustered, and glabrous. Leaves are ovate, base is truncate to cordate, entire margins, and acute tips.

Flowers

Flowers are white to pink, 0.16-0.24 in. (4-6 mm), tepals are obovate to elliptic, and apex is obtuse to acute. Flowering occurs between July and October.

Fruit

The fruits are dark brown in color, shiny, 0.08-0.12 (2-3 mm) long, smooth, and three sided with flat wings that are 0.06-0.08 in. (1.5-2.1 mm) wide.

Ecological Threat

Fallopia x bohemica prefers disturbed areas such as fields, pastures, and along roadsides and railways. It is native to Japan.

Selected Images

Maps

Invasive Listing Sources

• Alberta Weed Control Act
• California Invasive Plant Council
• California Noxious Weeds
• Colorado Noxious Weeds
• Idaho Noxious Weeds
• Illinois Exotic Weed Act
• Indiana Invasive Species Council - Invasive Plant List
• Indiana Terrestrial Plant Rule
• Minnesota Noxious Weeds
• Montana Noxious Weeds
• Native Plant Society of Oregon, 2008
• Nebraska Noxious Weeds
• New Hampshire Prohibited Invasive Species
• New York Regulated and Prohibited Invasive Species - Prohibited
• Ohio Invasive Species Council
• Ontario’s Invading Species Awareness Program Tracked Species List
• Oregon Noxious Weeds
• Pacific Northwest Exotic Pest Plant Council, 1998
• Pennsylvania Department of Conservation and Natural Resources Invasive Plants
• Washington Noxious Weeds
• Wisconsin Noxious Weeds
• Wisconsin's Invasive species rule – NR 40

References