Plant: annual; stems < 10 dm, slender, tough; axillary spines < 3 cm, 3-branched, stout, golden Leaves: alternate, short-petioled; blades generally 3-10 cm, linear to elliptic, subentire to pinnately lobed, white-hairy below, gray-green above; base generally 1-veined Inflorescence: primary inflorescence a head, each resembling a flower; staminate heads in clusters, involucre 0, receptacle chaffy; pistillate heads generally 1 (few in upper axils); phyllaries 0 or minute; chaff scales many, spirally arrayed, fused below, free tips spiny, hooked Flowers: Staminate flowers many; corolla translucent; filaments fused, attached to corolla tube base, anthers free; ovary slender; Pistillate flowers generally 2 per head; corolla 0; style branches long Fruit: Fruit: phyllaries 0 or minute; chaff scales many, spirally arrayed, fused below, free tips spiny, hooked; bur cylindric; spines slender; germinating in successive years; pappus 0 Misc: Disturbed areas; < 900 m.