Calflora
Taxon  Report   11015    
Persicaria wallichii  Greuter & Burdet
Himalayan knotweed
Persicaria wallichii, a dicot, is a perennial herb that is not native to California; it was introduced from elsewhere and naturalized in the wild. There is a high risk of this plant becoming invasive in California according to Cal-IPC.
Observation Hotline
(observation details)
one or more occurrences
within a 7.5-minute quadrangle

Bloom Period
Family: POLYGONACEAE  
Genus: Persicaria
Wetlands: Equally likely to occur in wetlands and non wetlands

Habitat: disturbed

Communities: weed, characteristic of disturbed places, wetland-riparian

Name Status:
Accepted by JEF

PLANTS accepted name:
Polygonum polystachyum

Alternate Names:
ICPN: Polygonum polystachyum
ICPN: Persicaria wallichii var. wallichii
More information about  Persicaria wallichii
Search efloras.org (Flora of North America)

Photos on 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 25, 2019).