[Fleeceflowers and Knotweeds: The Genera Aconogonon, Bistorta, Fagopyrum, Fallopia, Persicaria and Polygonum East of the Cascades of Oregon and Washington]
Douglas' Knotweed
Polygonum douglasii
Synonyms: Polygonum buxiforme var. montanum, Polygonum douglasii ssp. douglasii, Polygonum douglasii var. douglasii, Polygonum douglasii var. latifolium, Polygonum emaciatum, Polygonum montanum
The photo above and below show close-ups of
the leaves and flowers of Douglas' knotweed as seen along road #6000 at about
2780' on the southeastern slopes of Mt. Adams..........May 29, 2005.
Note that the tepals are cleft more than one-half their length.
Douglas' knotweed as seen along the Umatilla Rim Trail #3080 on the western slopes of High Ridge, Umatilla National Forest...........July 24, 2012.
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Douglas' knotweed as seen in lithosol soils along Forest Service Road 35 on Table Mountain, Wenatchee National Forest.........June 4, 2013.
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Douglas' knotweed as seen along the South Loop Road about one mile downhill from the Kiger Gorge overlook, Steens Mountain, Harney County, Oregon........September 2, 2011.
Douglas' knotweed as seen in moist meadows along the South Loop Road about one mile downhill from the East Rim Viewpoint, Steens Mountain, Harney County, Oregon.........September 2, 2011.
Paul Slichter
