Herbs, erect to spreading, annual, 1-5 dm, thinly tomentose, green-ish, grayish, or reddish. Stems: caudex absent; aerial flowering stems erect, not striated but sometimes angled, solid, not fistulose, 0.1-0.8 dm, tomentose. Leaves basal and cauline; basal: petiole 0.5-1 cm, floccose; basal blade oblanceolate to oblong, 2-4 × 0.3-1 cm, tomentose abaxially, floccose to glabrate and grayish or greenish adaxially, margins crenulate, often slightly revolute; cauline sessile, blade narrowly oblong, 0.5-2(-6) × 0.2-0.8(-1.5) cm, similar to basal blade. Inflorescences cymose, mostly open, 5-35 × 5-35 cm; branches thinly tomentose; bracts 3, scalelike, 1-3 × 1-2.5 mm. Peduncles spreading, straight, capillary, 0.8-2.5 cm, glabrous. Involucres campanulate, 1.8-2 × 2-3 mm, glandular-puberulent, not densely tomentose adaxially; teeth 5, erect, 0.4-0.8 mm. Flowers 2-2.5 mm; perianth white to rose, glandular-puberulent; tepals monomorphic, oblong to elliptic; stamens included, 1-2 mm; filaments pilose proximally. Achenes light brown, 3-gonous, 1-1.2(-1.5) mm, glabrous. 2n = 40.
Flowering year-round. Sandy to gravelly or clayey flats and slopes, mixed grassland, chaparral, saltbush, and creosote bush communities, oak and conifer woodlands; 0-1100 m; Calif.
Eriogonum gracillimum is found in the Coast, Transverse, and scattered mountain desert ranges in Fresno, Inyo, Kern, Kings, Los Angeles, Madera, Merced, Monterey, Riverside, San Benito, San Bernardino, San Diego, San Luis Obispo, Santa Barbara, and Tulare counties. The species is often common and occasionally even weedy.