Cottam's wild buckwheat

Eriogonum tenellum Torrey subsp. cottamii S. Stokes, Eriogonum, 70. 1936 (as cottami)

Plants erect, 1-3.5 × 2-5 dm. Aerial flowering stems erect, 0.5-2 dm, tomentose. Leaves: blade narrowly oblanceolate to narrowly elliptic; leaf blades (2-)3-4(-4.5) × 0.3-0.5(-0.7) cm, margins plane. Inflorescences cymose, usually divided 3 or more times, 2-7 cm; branches tomentose. Involucres usually 1 per node, turbinate, 2-3(-3.5) × 1.5-2(-2.5) mm, tomentose. Flowers (2.5-)3-4 mm; perianth yellow, glabrous.

Flowering Jun-Sep. Gravelly limestone slopes and clay hills, sagebrush communities, oak and pinyon-juniper woodlands; 1300-2100 m; Utah.

Variety cottamii is infrequent in the desert ranges west of the Wasatch Range in eastern portions of Juab, Millard, and Tooele counties, the southwestern corner of Salt Lake County, and in western Utah County. The attractive tomentum of Cottam's wild buckwheat changes from a gray to tannish- or reddish-brown as the plant matures, and the species is worthy of horticultural consideration. The narrow leaf blades of var. cottamii readily distinguish it from the more western E. natum.