[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, 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.

Mat Buckwheat, Matted Wild Buckwheat: Eriogonum caespitosum (Synonyms: Eriogonum cespitosum, Eriogonum sphaerocephalum var. sericoleucum)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.


Mat Buckwheat, Matted Buckwheat, Matted Wild Buckwheat: Eriogonum caespitosum (Synonyms: Eriogonum cespitosum, Eriogonum sphaerocephalum var. sericoleucum) - Mat Buckwheat, Matted Buckwheat, Matted Wild Buckwheat: Eriogonum caespitosum (Synonyms: Eriogonum cespitosum, Eriogonum sphaerocephalum var. sericoleucum) - Mat Buckwheat, Matted Buckwheat, Matted Wild Buckwheat: Eriogonum caespitosum (Synonyms: Eriogonum cespitosum, Eriogonum sphaerocephalum var. sericoleucum)

Mat buckwheat blooming on clifftops at the head of Kiger Gorge, Steens Mountain..........July 12, 2014.

Mat Buckwheat, Matted Buckwheat, Matted Wild Buckwheat: Eriogonum caespitosum (Synonyms: Eriogonum cespitosum, Eriogonum sphaerocephalum var. sericoleucum) - Mat Buckwheat, Matted Buckwheat, Matted Wild Buckwheat: Eriogonum caespitosum (Synonyms: Eriogonum cespitosum, Eriogonum sphaerocephalum var. sericoleucum)

Close-ups of mat buckwheat as seen at the Steens Mountain summit in southeastern Oregon........September 1, 2011.

Mat Buckwheat, Matted Buckwheat, Matted Wild Buckwheat: Eriogonum caespitosum (Synonyms: Eriogonum cespitosum, Eriogonum sphaerocephalum var. sericoleucum)

Mat Buckwheat, Matted Buckwheat, Matted Wild Buckwheat: Eriogonum caespitosum (Synonyms: Eriogonum cespitosum, Eriogonum sphaerocephalum var. sericoleucum) - Mat Buckwheat, Matted Buckwheat, Matted Wild Buckwheat: Eriogonum caespitosum (Synonyms: Eriogonum cespitosum, Eriogonum sphaerocephalum var. sericoleucum)

Additional close-ups of mat buckwheat as seen at the East Rim Viewpoint, Steens Mountain, Harney County, Oregon........September 1, 2011.

Mat Buckwheat, Matted Buckwheat, Matted Wild Buckwheat: Eriogonum caespitosum (Synonyms: Eriogonum cespitosum, Eriogonum sphaerocephalum var. sericoleucum) - Mat Buckwheat, Matted Buckwheat, Matted Wild Buckwheat: Eriogonum caespitosum (Synonyms: Eriogonum cespitosum, Eriogonum sphaerocephalum var. sericoleucum)

Mat Buckwheat, Matted Buckwheat, Matted Wild Buckwheat: Eriogonum caespitosum (Synonyms: Eriogonum cespitosum, Eriogonum sphaerocephalum var. sericoleucum) - Mat Buckwheat, Matted Buckwheat, Matted Wild Buckwheat: Eriogonum caespitosum (Synonyms: Eriogonum cespitosum, Eriogonum sphaerocephalum var. sericoleucum)

Mat Buckwheat, Matted Buckwheat, Matted Wild Buckwheat: Eriogonum caespitosum (Synonyms: Eriogonum cespitosum, Eriogonum sphaerocephalum var. sericoleucum)

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.

Mat Buckwheat, Matted Buckwheat, Matted Wild Buckwheat: Eriogonum caespitosum (Synonyms: Eriogonum cespitosum, Eriogonum sphaerocephalum var. sericoleucum) - Mat Buckwheat, Matted Buckwheat, Matted Wild Buckwheat: Eriogonum caespitosum (Synonyms: Eriogonum cespitosum, Eriogonum sphaerocephalum var. sericoleucum)

Mat buckwheat as seen near the East Rim Viewpoint, Steens Mountain..........July 11, 2014.

Mat Buckwheat, Matted Buckwheat, Matted Wild Buckwheat: Eriogonum caespitosum (Synonyms: Eriogonum cespitosum, Eriogonum sphaerocephalum var. sericoleucum) - Mat Buckwheat, Matted Buckwheat, Matted Wild Buckwheat: Eriogonum caespitosum (Synonyms: Eriogonum cespitosum, Eriogonum sphaerocephalum var. sericoleucum)

Mat Buckwheat, Matted Buckwheat, Matted Wild Buckwheat: Eriogonum caespitosum (Synonyms: Eriogonum cespitosum, Eriogonum sphaerocephalum var. sericoleucum) - Mat Buckwheat, Matted Buckwheat, Matted Wild Buckwheat: Eriogonum caespitosum (Synonyms: Eriogonum cespitosum, Eriogonum sphaerocephalum var. sericoleucum)

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.

Mat Buckwheat, Matted Buckwheat, Matted Wild Buckwheat: Eriogonum caespitosum (Synonyms: Eriogonum cespitosum, Eriogonum sphaerocephalum var. sericoleucum) - Mat Buckwheat, Matted Buckwheat, Matted Wild Buckwheat: Eriogonum caespitosum (Synonyms: Eriogonum cespitosum, Eriogonum sphaerocephalum var. sericoleucum)

Mat buckwheat as seen at the summit of Sugarloaf Mountain several miles north of Fish Lake Campground, Wallowa-Whitman National Forest......August 13, 2018.

Flower head of Mat Buckwheat, Matted Wild Buckwheat: Eriogonum caespitosum (Synonyms: Eriogonum cespitosum, Eriogonum sphaerocephalum var. sericoleucum) - Basal leaves of Mat Buckwheat, Matted Wild Buckwheat: Eriogonum caespitosum (Synonyms: Eriogonum cespitosum, Eriogonum sphaerocephalum var. sericoleucum)

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.

Mat Buckwheat, Matted Wild Buckwheat: Eriogonum caespitosum (Synonyms: Eriogonum cespitosum, Eriogonum sphaerocephalum var. sericoleucum)

Eriogonum caespitosum from Hart Mt, Hart Mt National Antelope Refuge, July 4, 1996.

Paul Slichter