Polygonum cuspidatum Siebold & Zucc.
(not an active name )
Japanese knotweed
2005 Louis-M. Landry
2006 Dr. Amadej Trnkoczy
Polygonum cuspidatum is a
perennial herb that is
not native to California.
Cal-IPC rating: moderate
Siskiyou
Del Norte
Modoc
Humboldt
Shasta
Lassen
Trinity
Plumas
Tehama
Butte
Mendocino
Glenn
Sierra
Yuba
Lake
Nevada
Colusa
Placer
Sutter
El Dorado
Yolo
Alpine
Napa
Sonoma
Sacramento
Mono
Amador
Solano
Calaveras
Tuolumne
San Joaquin
Marin
Contra Costa
Alameda
Santa Cruz
Mariposa
Madera
San Francisco
San Mateo
Merced
Fresno
Stanislaus
Santa Clara
Inyo
San Benito
Tulare
Kings
Monterey
San Bernardino
San Luis Obispo
Kern
Santa Barbara
Ventura
Los Angeles
Riverside
Orange
San Diego
Imperial
one or more occurrences within a 7.5-minute quadrangle
Information about
Polygonum cuspidatum
from other sources
0000 0000 0105 2341:!0000 0000 0306 0139:!
2005 Louis-M. Landry:!2006 Dr. Amadej Trnkoczy:!
null:!null:!
Suggested Citation
Calflora :
Information on California plants for education, research and conservation,
with data contributed by
public and private institutions and individuals.
[web application]. 2024. Berkeley, California:
The Calflora Database
[a non-profit organization].
Available:
https://www.calflora.org/
(Accessed: 11/21/2024).