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Perennials [subshrubs], 6–80 cm (usually rhizomatous, sometimes fibrous rooted or taprooted; usually aromatic). Stems 1(–4+, clustered), usually erect, branched mostly distally, glabrous or sparsely to densely lanate (hairs usually basifixed). Leaves basal (often withering before flowering) and cauline; alternate; petiolate or sessile (bases ± clasping); blades (cauline equaling basal or slightly smaller distally) linear to oblong-lanceolate, usually 1–2[–4]-pinnately lobed, ultimate margins entire, abaxial faces sparsely to densely lanate, adaxial faces glabrate to sparsely tomentose. Heads radiate [discoid], in compact to open (± flat-topped), simple or compound, corymbiform arrays [borne singly]. Involucres campanulate to hemispheric, mostly 2–3(–5+) mm diam. Phyllaries persistent, 10–30 in (1–)2–3(–4) series, oblong, ovate, or oblanceolate to lanceolate (midribs conspicuous), unequal, margins and apices (pale to black) scarious. Receptacles usually flat to slightly convex, rarely conic, paleate; paleae membranous, ± folded (sometimes each with central resin duct). Ray florets [0] 3–5(–12+), usually pistillate and fertile; corollas usually white (laminae yellow at bases), sometimes pale yellow to pink or purple (tubes ± flattened), laminae orbiculate to suborbiculate (becoming reflexed). Disc florets usually (5–)15–75+, rarely 0, bisexual, fertile; corollas white to grayish or yellowish [yellow, pink], tubes ± flattened (bases ± saccate, clasping apices of cypselae), throats ± campanulate, lobes 5, ± deltate. Cypselae obcompressed, oblong to obovate (margins sometimes winged, apices rounded); ribs usually 2, lateral (sometimes plus 1 adaxial), faces glabrous (pericarps with myxogenic cells, sometimes with resin sacs; embryo sac development monosporic). x = 9.