Taxon  Report   6748 
Polygonum douglasii  E. Greene
Douglas' knotweed
Polygonum douglasii
© 2003 Michael Charters
Click on a photo to see it bigger.
Polygonum douglasii
© 2012 Jean Pawek
Polygonum douglasii
© 2009 Barry Breckling
Polygonum douglasii, a dicot, is an annual herb that is native to California and is also found elsewhere in North America and beyond.

Interactive Distribution Map

Observation Hotline
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Plant Characteristics
and Associations

Bloom Period
Polygonum douglasii
© 2009 Barry Breckling
Genus: Polygonum
Yellow Pine Forest, Red Fir Forest, Lodgepole Forest, Subalpine Forest, Sagebrush Scrub
Habitat: meadows [Walker]
Wetlands:Usually occurs in non wetlands, but occasionally found in wetlands [U.S. Fish & Wildlife Service.]
Distribution by County 

Add an Observation of  Polygonum douglasii

Name Status:
Accepted by TJM2 + PLANTS + JM93
Alternate Names:
(according to)

TJM2: Polygonum buxiforme
TJM2: Polygonum douglasii ssp. douglasii
More information about  Polygonum douglasii
Jepson eFlora

Records from the Consortium of California Herbaria

Original Publication citation (ITIS)


Search the International Plants Names Index

Search (Flora of North America)

Search the Lady Bird Johnson Wildflower Center

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]. 2016. Berkeley, California: The Calflora Database [a non-profit organization].
Available:   (Accessed: Oct 23, 2016).

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