Polygonum amphibium Calflora

Calflora, a 501c3 non-profit

Taxon Report

Polygonum amphibium L.

(not an active name)

Swamp knotweed, Water knotweed, Water smartweed

2003 Tom Annese

2006 Matt Below

Polygonum amphibium is a perennial herb that is native to California, and also found elsewhere in North America and beyond.

also called Persicaria amphibia


	Plant Range Observation Search ~550 records in California Plant Characteristics

Bloom Period

Photos on Calflora


Genus:	Polygonum
Family:	Polygonaceae
Category:	angiosperm
PLANTS group:	Dicot
Jepson eFlora section: eudicot

Communities: Yellow Pine Forest, Red Fir Forest, Lodgepole Forest, Subalpine Forest, Foothill Woodland, Chaparral, Valley Grassland, wetland-riparian, many plant communities

Name Status:
Accepted by PLANTS

Alternate Names:


JEF	Persicaria amphibia

Information about Polygonum amphibium from other sources


Nursery availability from CNPLX This plant is available commercially. USDA PLANTS Profile (POAM8) Photos on Calflora Photos on CalPhotos Google Images Photos on iNaturalist ID Tips on PlantID.net	ITIS Original Publication citation International Plants Names Index Search efloras.org (Flora of North America) Landscape information from Calscape BONAP Distribution Map Consortium of California Herbaria 2 Search the Native American Ethnobotany Database	Add an Observation Location Suitability Planting Guide Distribution by County
photos / record / common / links 2003 Tom Annese:!2006 Matt Below:! null:!null:!

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).