Polygonum cuspidatum (Japanese knotweed). . , Family: Polygonaceae (Knotweed Family), Distribution: Japanese knotweed can be found throughout North America with the exception of a few southern states and central Canada. It is present in almost every county in West Virginia., Size: This plant can reach heights up to 12 ft., Habitat/Description: This herbaceous perennial, which appears woody, can grow in a wide range of habitats, including roadsides, waste places, streambanks, wet lands, riparian areas, and neglected gardens. It tolerates dry soil, salt, and high temperatures very well. It prefers sunlight, but is tolerant of mild to moderate shade. Numerous, attractive white inflorescences with tiny flowers appear between July and October. The winged, papery fruits contain smooth, shiny black, triangular seeds. Japanese knotweed aggressively forms dense, persistent thickets that overtake other neighboring foliage. This is a problem because such severely altered habitats may negatively affect wildlife. These thickets grow in size very quickly because this plant reproduces vegetatively by vigorous rhizomes that form a dense mat. As a result, populations are difficult to eradicate. Plants can even penetrate asphalt! This is a severely invasive, non-native species., Ethnobotanical Uses: Japanese knotweed is a native of Asia. Sometime after 1830, this plant was introduced to Europe. It was widely distributed in plant catalogs, but as the aggressive nature of the plant was discovered, it began to decline in popularity. In the late 1800s, Japanese knotweed was brought to the United States for horticultural use, and it soon escaped cultivation. It quickly became naturalized in Pennsylvania, New York, New Jersey, and surrounding areas. By the 1930s, invasiveness had become such an issue that catalogs began publishing information about how to eradicate it from gardens. When the Cherokee encountered it, they used Japanese knotweed as a leafy vegetable. Young shoots may be eaten as a tasty potherb.
Family: Polygonaceae (Knotweed Family)
Distribution: Japanese knotweed can be found throughout North America with the exception of a few southern states and central Canada. It is present in almost every county in West Virginia.
Size: This plant can reach heights up to 12 ft.
Habitat/Description: This herbaceous perennial, which appears woody, can grow in a wide range of habitats, including roadsides, waste places, streambanks, wet lands, riparian areas, and neglected gardens. It tolerates dry soil, salt, and high temperatures very well. It prefers sunlight, but is tolerant of mild to moderate shade. Numerous, attractive white inflorescences with tiny flowers appear between July and October. The winged, papery fruits contain smooth, shiny black, triangular seeds. Japanese knotweed aggressively forms dense, persistent thickets that overtake other neighboring foliage. This is a problem because such severely altered habitats may negatively affect wildlife. These thickets grow in size very quickly because this plant reproduces vegetatively by vigorous rhizomes that form a dense mat. As a result, populations are difficult to eradicate. Plants can even penetrate asphalt! This is a severely invasive, non-native species.
Ethnobotanical Uses: Japanese knotweed is a native of Asia. Sometime after
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1830, this plant was introduced to Europe. It was widely distributed in plant catalogs, but as the aggressive nature of the plant was discovered, it began to decline in popularity. In the late 1800s, Japanese knotweed was brought to the United States for horticultural use, and it soon escaped cultivation. It quickly became naturalized in Pennsylvania, New York, New Jersey, and surrounding areas. By the 1930s, invasiveness had become such an issue that catalogs began publishing information about how to eradicate it from gardens. When the Cherokee encountered it, they used Japanese knotweed as a leafy vegetable. Young shoots may be eaten as a tasty potherb.
Erected 2017 by West Virginia Wesleyan College Department of Biology.
Location. 38° 59.611′ N, 80° 13.065′ W. Marker is in Buckhannon, West Virginia, in Upshur County. It can be reached from Camden Avenue north of Walktrail Lane, on the left when traveling north. Marker is located on the Buckhannon Nature Park and Learning Trail west of the Camden Avenue parking area. Touch for map. Marker is at or near this postal address: 8 Camden Avenue, Buckhannon WV 26201, United States of America. Touch for directions.
Regionally, this marker is in North Central West Virginia. It is also in the American South, specifically in the Upper South, in Appalachia, and specifically in Northern Appalachia. Globally, it is in North America, the Western Hemisphere, the Western World, and the Anglosphere. Historically, it finds itself in what was once the territory of the Mississippian Culture.
Credits. This page was last revised on March 6, 2025. It was originally submitted on March 6, 2025, by Bradley Owen of Morgantown, West Virginia. This page has been viewed 135 times since then and 11 times this year. Photos:1, 2. submitted on March 6, 2025, by Bradley Owen of Morgantown, West Virginia.
