American Bistort, Snakeweed, Mountain Meadow Knotweed, Western Bistort
Synonyms: Persicaria bistortoides, Polygonum bistortoides, Polygonum bistortoides var. linearifolium, Polygonum bistortoides var. oblongifolium, Polygonum cephalophorum, Polygonum glastifolium, Polygonum vulcanicum
American bistort blooming along FS Road #27 in Thompson Valley, Fremont National Forest.......May 19, 2016.
American bistort is an erect perennial arising 30-60 cm from
a thick tuber. The basal leaves are long petiolate and not jointed to the stem.
The leaf blade is oblong-lanceolate or wider, to 15 cm long. The stipules are
brownish and 3-6 cm long. There are a few lanceolate stem leaves, reduced in
size upwards on the stem. The inflorescence is a terminal raceme, spike-like,
from 3-6 cm longand 1-2 cm wide. It is densely white-flowered as seen in the
American bistort is a montane species found in moist or swampy
meadows, streambanks, or alpine slopes.
American bistort is found from southern Alaska to southern California,
east to Alberta, Montana, and New Mexico.
American bistort blooming along a small creek along the South Loop Road about one mile downhill from the East Rim Viewpoint, Steens Mountain, Harney County, Oregon........August 31, 2011.
American bistort observed in bloom along FS Road 4215 about 100 meters south of the junction with FS Road 4220, Ochoco National Forest.......May 19, 2018.
The photo at left shows a close-up of the inflorescence of american bistort as seen on moist grassland slopes in Zumwalt Prairie between Buckhorn Lookout and Enterprise, OR........June 27, 2008. The photo at right shows a close-up of the inflorescence of american bistort about 2.5 miles upstream along the upper Sycan River from the trailhead along the Hanan Trail #142, Fremont-Winema National Forest.....June 17, 2020..
American bistort as seen at the north trailhead for Baldy Mountain, Malheur National Forest........July 1, 2010.
A wet meadow full of american bistort as seen about one mile downhill from the Kiger Gorge Overlook, Steens Mountain, Harney County, Oregon........August 31, 2011. The photo at right shows a late blooming american bistort as seen in wet riparian meadows along the South Loop Road about one mile west of the East Rim Viewpoint, Steens Mountain..........September 20, 2015.