[Buckwheats: The Genus Eriogonum East of the
Cascade Mts. of Oregon and Washington]
Mat Buckwheat, Matted Buckwheat, Matted Wild Buckwheat
Eriogonum caespitosum
Synonyms: Eriogonum cespitosum, Eriogonum sphaerocephalum var. sericoleucum
Mat buckwheat as seen from the summit of the Steens Mountain, Harney County, OR.........September 1, 2011.
Photo at right
of Eriogonum caespitosum from Hart Mt, Hart Mt. National Antelope Refuge.
Note the lack of leaves or bracts both on the stem and directly below the inflorescence.
Characteristics:
Mat buckwheat is a cushion plant with spreading branches from
5-20 cm long and scapes to 8 cm tall. The numerous grayish leaves are spatulate
in shape, 5-20 mm long (which includes the petiole) and tomentose on both surfaces.
The flower scapes lack cauline (stem) leaves. The inflorescence
is a single, tight umbel (consisting of 1 involucre) with the flowers often
reflexed downward. The involucre is a shallow bowl with approximately 6-10 narrow,
oblong and unequal, reflexed lobes about as long as the bowl. The flowers are
yellow, reddish tinged, and from 5-6 mm long. The outer segments are oblong
or elliptic in shape while the inner are smaller and obovate in shape. The outer
surface of the involucre as well as the perianth is tomentose.
Mat buckwheat is also known as cushion buckwheat.
Habitat:
Mat buckwheat is found interspersed with sagebrush from the
foothills to mountain ridges.
Range:
Mat buckwheat may be found from southeast Oregon to southeast
California, east to central Idaho, Montana, Wyoming and Colorado.
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Mat buckwheat blooming on clifftops at the head of Kiger Gorge, Steens Mountain..........July 12, 2014.
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Close-ups of mat buckwheat as seen at the Steens Mountain summit in southeastern
Oregon........September 1, 2011.
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Additional close-ups of mat buckwheat as seen at the East Rim Viewpoint, Steens Mountain, Harney County, Oregon........September 1, 2011.
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Mat buckwheat covering rocks on shallow lithosol soils atop the Hart Mt. ridgeline just northeast of the head of DeGarmo Canyon, Hart Mt. National Antelope Refuge..........June 9, 2016.
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Mat buckwheat as seen near the East Rim Viewpoint, Steens Mountain..........July 11, 2014.
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What appears to be mat buckwheat as seen on cindery slopes at Domingo Pass, Pueblo Mts. of southeastern Oregon..............May 31, 2012. Without a closer view of the inflorescence, these could also be Crosby's buckwheat (Eriogonum crosbyae) which is also present in this area.
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Mat buckwheat as seen at the summit of Sugarloaf Mountain several miles north of Fish Lake Campground, Wallowa-Whitman National Forest......August 13, 2018.
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Mat buckwheat in bloom atop Light Peak, Fremont-Winema National Forest......June 29, 2019.
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Mat buckwheat as seen at left at the summit of Sugarloaf Mountain several miles north of Fish Lake Campground, Wallowa-Whitman National Forest......August 18, 2019. The photo at right shows mat buckwheat in bloom at about 7400' along the Fremont National Recreation Trail #160 on the southeastern shoulder of Crook Peak, Fremont-Winema National Forest......June 28, 2019.
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Additional close-ups of the inflorescence and leaves
of mat buckwheat as seen at Domingo Pass in the Pueblo Mts. of southeastern
Oregon, June 25, 1999.
Eriogonum caespitosum from Hart
Mt, Hart Mt National Antelope Refuge, July 4, 1996.
Paul Slichter