Stems 5-80 cm. Leaves: petiole ca. 2-15 mm or absent; blade 2-7(-8) × 0.5-2 cm, base cuneate, margin teeth acute or mucronulate. Perianths 2-4.5 mm diam. (including wing), ± tomentose, often becoming glabrous and reddish. Seeds 1.5 mm diam. 2n = 36. Flowering late summer-fall. Sandy soils, roadsides, waste places, disturbed and alluvial habitats, fields, deserts and prairies (obligate psammophyte); 0-1500 m; Man., Ont., Que., Sask.; Ariz., Ark., Calif., Colo., Conn., Ill., Ind., Iowa, Kans., Ky., La., Md., Mass., Mich., Minn., Mo., Mont., Nebr., N.J., N.Mex., N.Y., N.C., N.Dak., Ohio, Okla., Pa., S.C., S.Dak., Tenn., Tex., Utah, Va., W.Va., Wis., Wyo.; n Mexico; introduced casual in Europe and some other parts of the world. The original distribution of Cycloloma atriplicifolium may have covered mostly central parts of North America west of the Mississippi River. Current distributions indicate a pattern of expansion. It appears to be spreading in southern Canada, especially the prairie provinces, and in the southeastern United States. Occurrences have been reported in Idaho, Maine, Nevada, New Hampshire, Vermont, Virginia, and West Virginia, but specimens have not been seen for these states.

Plant: Annual 12-75 cm, rounded; stem with many spreading branches, slender, striate, finely woolly, becoming glabrous Leaves: gradually reduced upward; petiole 0-12 mm; blade 5-65 mm, lanceolate to ovate, ± wavy-toothed INFLORESCENCE: panicle-like, terminal, open in fruit; bracts 0; flowers sessile Flowers: generally bisexual (pistillate); calyx enclosing fruit, 2-3 mm diam in fruit, winged, lobes 5, ± keeled; stamens 5; ovary densely and finely tomentose, style deeply 2-3-lobed Fruit: utricle, ± 2 mm diam; Seed 1.5-2 mm, horizontal, black Misc: Fields, disturbed sites; < 800 m.; May-Sep