Shrubs, dioecious, erect, intricately much branched, mainly 3-15 dm; branchlets terete, becoming rigid and spinose. Leaves short petiolate to sessile; blade ovate-deltate to elliptic or spatulate, (5-)10-27 mm, entire or subhastate. Staminate flowers borne in small axillary glomerules. Pistillate flowers borne solitary or few in bract axils on short, spinose, lateral branchlets of a paniculate inflorescence. Fruiting bracteoles sessile or nearly so, body globose, connate, constricted below oblong to orbicular wings, 7-15 ×3.5-10 mm, entire or obscurely dentate, faces smooth to sparingly cristate. Seeds reddish brown, 2-2.8 mm.

Flowering summer-fall. Xeric saline substrates, with mixed salt desert shrubs; 30-1300 m; Calif.

Spiny saltbush apparently forms occasional hybrids with phases of Atriplex canescens, as indicated by the presence of wings on some of the fruiting bracteoles.