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Taxon  Report  
Polygonum cuspidatum  Siebold & Zucc.

(not an active name)

Japanese knotweed
Polygonum cuspidatum is a perennial herb that is not native to California.
also called Fallopia japonica
Cal-IPC rating: moderate
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Observation Search
~505 records in California
redone or more occurrences
within a 7.5-minute quadrangle
Genus: Polygonum
Family: Polygonaceae  
Category: angiosperm  
PLANTS group:Dicot
Jepson eFlora section: eudicot

Communities: escaped cultivar
Name Status:
Accepted by PLANTS

Alternate Names:
PLANTSFallopia japonica
PLANTSPleuropterus cuspidatus
PLANTSPleuropterus zuccarinii
PLANTSPolygonum cuspidatum var. compactum
PLANTSPolygonum zuccarinii
...
Information about  Polygonum cuspidatum from other sources
USDA PLANTS Profile (POCU6)

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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: 11/21/2024).