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Taxon  Report  
Polygonum sawatchense  Small  ssp. sawatchense 
Knotweed
Polygonum sawatchense ssp. sawatchense is an annual or perennial herb that is native to California, and also found elsewhere in western North America.
Siskiyou Del Norte Modoc Humboldt Shasta Lassen Trinity Plumas Tehama Butte Mendocino Glenn Sierra Yuba Lake Nevada Colusa Placer Sutter El Dorado Yolo Alpine Napa Sonoma Sacramento Mono Amador Solano Calaveras Tuolumne San Joaquin Marin Contra Costa Alameda Santa Cruz Mariposa Madera San Francisco San Mateo Merced Fresno Stanislaus Santa Clara Inyo San Benito Tulare Kings Monterey San Bernardino San Luis Obispo Kern Santa Barbara Ventura Los Angeles Riverside Orange San Diego Imperial
bloom graphic
Bloom Period
Parent: Polygonum sawatchense
Genus: Polygonum
Family: Polygonaceae  
Category: angiosperm  
PLANTS group:Dicot
Jepson eFlora section: eudicot

Wetlands: Occurs usually in non wetlands, occasionally in wetlands
Name Status:
Accepted by JEF

Alternate Names:
JEFPolygonum douglasii ssp. johnstonii
JEFPolygonum douglasii var. johnstonii
JEFPolygonum exile
JEFPolygonum triandrum
Information about  Polygonum sawatchense ssp. sawatchense from other sources
Nursery availability from CNPLX
Commercial availability unknown.
Jepson eFlora

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ID Tips on PlantID.net

International Plants Names Index

Search efloras.org (Flora of North America)

Landscape information from Calscape

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: 01/29/2023).