Herbs, erect, annual, (0.5-)1-6(-10) dm, glabrous, green. Stems: caudex absent; aerial flowering stems erect, usually hollow and fistulose, 0.5-2 dm, glabrous. Leaves basal or sheathing up stems 1-6 cm; petiole 1-10 cm, pilose-hispid; blade subcordate, (0.5-)1-4(-6) × (0.5-)1-5(-7) cm, pilose-hispid and bright green on both surfaces, margins plane. Inflorescences narrowly cymose, open, 5-80 × 5-35(-40) cm; branches often fistulose, glabrous; bracts 3, scalelike, 1-4 × 0.5-2 mm. Peduncles deflexed, straight, slender, (0.05-)0.1-0.25 cm, glabrous. Involucres turbinate, 1.2-1.6 × 1-1.4 mm, glabrous; teeth 5, erect, 0.4-0.6 mm. Flowers 1-2.5 mm; perianth greenish white to reddish, glabrous; tepals monomorphic, oblong; stamens included to exserted, 1-1.5 mm; filaments glabrous. Achenes dark greenish brown to black, 3-gonous, 1.4-1.7 mm, glabrous. 2n = 40. Flowering May-Sep. Sandy to gravelly flats, washes, and slopes, saltbush and sagebrush communities, pinyon-juniper woodlands; of conservation concern; 1400-2100 m; Nev. Eriogonum concinnum is locally common on the mesas of the U.S. Department of Energy's Nevada Test Site east and north of Beatty, Nye County. Although the area is subject to considerable habitat destruction, the species seems to be surviving and is neither threatened nor endangered, although it is properly considered a 'sensitive' species given its limited range and the potential for more profound habitat destruction in the area.