Calflora
Taxon  Report   6748    
Polygonum douglasii  Greene
Douglas' knotweed
Polygonum douglasii
© 2003 Michael Charters
Photos from
CalPhotos / Calflora
Polygonum douglasii
© 2009 Barry Breckling
Polygonum douglasii
© 2016 Judy and Barry Breckling
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 + photos)



point, line, or polygon

Plant Characteristics
and Associations



Bloom Period
Polygonum douglasii
© 2012 Jean Pawek
Family: POLYGONACEAE  
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 PlantID.net   /   Google Images
Jepson eFlora

Records from the Consortium of California Herbaria

ITIS Original Publication citation

USDA PLANTS Profile (PODO4)

Search the International Plants Names Index

Search efloras.org (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]. 2018. Berkeley, California: The Calflora Database [a non-profit organization].
Available: https://www.calflora.org/   (Accessed: Nov 17, 2018).

The information on this page comes from diverse sources. None of the links are sponsored.