Herbs, perennial [annual], often densely cespitose, rosulate [caulescent]. Roots appearing unbranched, pale, not septate, thickened, spongy. Stems simple [branched], short [to very elongate]. Leaves spreading in flat spiral in rosettes [spreading to erect in high spiral]; blade mostly slender, linear, not evidently lacunate [lacunate], base pale. Inflorescences: scape sheaths narrowly tubular, orifice diagonal, surfaces tomentose to scattered pilosulous, glandular-hairy [glabrous]; scapes 1--several per stem, slender, terete [compressed], pubescent [glabrous to variously pubescent], at least some hairs swollen basally, often glandular distally; mature heads white [dark], hemispheric to globose [turbinate, urceolate]; receptacle pale, pilose with sharp hairs; involucral bracts spreading to ascending, mostly not obscured by expanding flowers, spirally imbricate, pale [brown or black], often gradate, chaffy-papery; receptacular bracts absent [few or reduced]. Flowers with staminate and pistillate on same plants [staminate and pistillate on different plants], 3-merous [2-merous]. Staminate flowers: sepals 3, nearly distinct, plane or concave, chaffy, often with tapering, acute hairs; androphore club-shaped or funnelform; petals 3, connate at apex of androphore, narrowly campanulate, 3-lobed, lobes low-triangular [to variously elongate]; stamens 3, low in corolla tube alternating with 3 sessile glands at base of tube; filaments low in corolla tube (at disc, midway), alternating with glands; anthers 2-locular, locules divergent, [2--]4-sporangiate, dorsifixed, exserted, yellowish or white. Pistillate flowers: gynophore short; sepals distinct [connate], papery; petals connate, conniving or connate over ovary; pistil 3-carpellate; style1; style branches 3, undivided.