Taxon  Report   6748    
Polygonum douglasii  Greene
Douglas' knotweed
Polygonum douglasii
© 2016 Judy and Barry Breckling
Photos from
CalPhotos / Calflora
Polygonum douglasii
© 2003 Michael Charters
Polygonum douglasii
© 2012 Jean Pawek
Polygonum douglasii, a dicot, is an annual herb that is native to California, is also found elsewhere in North America and beyond.

Interactive Distribution Map

Observation Hotline
(observation details)

point, line, or polygon

Plant Characteristics
and Associations

Bloom Period
Polygonum douglasii
© 2009 Barry Breckling
Genus: Polygonum
Communities: Yellow Pine Forest, Red Fir Forest, Lodgepole Forest, Subalpine Forest, Sagebrush Scrub

Wetlands: Occurs usually in non wetlands, occasionally in wetlands

Habitat: meadows

Name Status:
Accepted by JEF + PLANTS

Alternate Names:
ICPN: Polygonum buxiforme
ICPN: Polygonum douglasii ssp. douglasii
More information about  Polygonum douglasii
Nursery / seed vendor availability from CNPLX
Commercial availability unknown.
Landscaping information from Calscape
Photos on   /   Google Images
Jepson eFlora

Records from the Consortium of California Herbaria

ITIS Original Publication citation


Search the International Plants Names Index

Search (Flora of North America)

website references from Google

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]. 2019. Berkeley, California: The Calflora Database [a non-profit organization]. Available:   (Accessed: Jan 19, 2019).