Long-leaf wild buckwheat

Eriogonum longifolium subsp. diffusum S. Stokes; E. longifolium var. lindheimeri Gandoger; E. longifolium var. plantagineum Engelmann & A. Gray; E. vespinum Shinners

Plants 3-20 dm, tomentose to nearly glabrous. Leaves: basal leaf blade 0.5-20 × 0.3-3 cm, tomentose abaxially, less so to floccose or nearly glabrous adaxially. Peduncles 0.3-3 cm. Involucres turbinate to campanulate, 4-6 × 2.5-6 mm. Flowers 5-11 mm, including 0.5-2.5 mm stipelike base. Achenes 4-6 mm.

Flowering May-Oct. Sandy to gravelly, often calcareous flats, slopes, and outcrops, mixed grassland, creosote bush, and mesquite communities, oak and conifer woodlands; 60-1100(-1300) m; Ark., Kans., La., Mo., N.Mex., Okla., Tex.

Variety longifolium is widespread and common in the south-central United States. Its roots were used as food by the Kiowa (P. A. Vestal and R. E. Schultes 1939), and an infusion of the roots was taken by the Comanche for stomach trouble (G. G. Carlson and V. H. Jones 1940).