Calflora
Taxon  Report   10891    
Fallopia japonica  (Houtt.) Ronse Decr.
Japanese knotweed
Fallopia japonica, a dicot, is a perennial herb that is not native to California. Cal-IPC rating: Moderate
Observation Hotline
(observation details)
one or more occurrences
within a 7.5-minute quadrangle

Bloom Period
Family: POLYGONACEAE  
Genus: Fallopia
Wetlands: Occurs usually in non wetlands, occasionally in wetlands

Communities: escaped cultivar

Name Status:
Accepted by JEF

PLANTS accepted name:
Polygonum cuspidatum

Alternate Names:
ICPN: Polygonum cuspidatum
ICPN: Reynoutria japonica
ICPN: Fallopia japonica var. japonica
More information about  Fallopia japonica
Search efloras.org (Flora of North America)

Photos on PlantID.net   /   Google Images

Consortium of California Herbaria


Suggested Citation
Calflora: Information on California plants for education, research and conservation, with data contributed by public and private institutions and individuals, including the Consortium of California Herbaria. [web application]. 2019. Berkeley, California: The Calflora Database [a non-profit organization]. Available: https://www.calflora.org/   (Accessed: Mar 20, 2019).