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 has been naturalized in the wild. There is a high risk of this plant becoming invasive in California according to Cal-IPC.
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Observation Search
(105 records)
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 ICPN

PLANTS other name:
Polygonum polystachyum

Alternate Names:
ICPN: Persicaria wallichii var. wallichii
ICPN: Polygonum polystachyum
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]. 2020. Berkeley, California: The Calflora Database [a non-profit organization]. Available: https://www.calflora.org/   (Accessed: Aug 13, 2020).