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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
~141 records in California
redone or more occurrences
within a 7.5-minute quadrangle
DJJJASONAFMM

Bloom Period
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

[Cal-IPC] Asia native, invasive: Persicaria wallichii (Himalayan knotweed) is a perennial herb/ (family Polygonaceae) with white flowers and narrow leaves found in the north and central coast ranges of California. It is native to south-central Asia. It favors grasslands, wetlands, bog and marsh, and riparian and bottomland habitat. It spreads via small fragments that form new plants. Means of dispersal include wind, water, animals and humans. (contributed by Mary Ann Machi)


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: 03/28/2024).