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Taxon  Report  
Persicaria wallichii  Greuter & Burdet
Himalayan knotweed
Persicaria wallichii is a perennial herb that is not native to California.
There is a high risk of this plant becoming invasive in California according to Cal-IPC.
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Observation Search
(132 records)
redone or more occurrences
within a 7.5-minute quadrangle
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Genus: Persicaria
Family: Polygonaceae  
Category: angiosperm  
PLANTS group:Dicot
Jepson eFlora section: eudicot

Wetlands: Equally likely to occur in wetlands and non wetlands

Habitat: disturbed

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

Name Status:
Accepted by JEF
Alternate Names:
JEFAconogonon polystachyum
JEFPersicaria polystachya
JEFPolygonum polystachyum
PLANTSPolygonum polystachyum
Information about  Persicaria wallichii from other sources
International Plants Names Index

Search efloras.org (Flora of North America)

Cal-IPC Profile rating: watch (high risk)

Consortium of California Herbaria 2


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]. 2023. Berkeley, California: The Calflora Database [a non-profit organization]. Available: https://www.calflora.org/   (Accessed: 01/30/2023).