Erect, mostly perennial herbs or subshrubs 10-60 (-120) cm tall, often arising from a creeping rootstock; stem striate, sometimes hollow, the branching dichot-omous, ascending, the branches to 30 cm long, strigose, with trichomes 1.0-1.8 mm long. Leaves cauline, the lower oblanceolate, basally attenuate, acute at apex, sinuate or more commonly sparsely serrate, 4-21 cm long, 2-6 cm wide, char-taceous, strigose and resin-dotted beneath, merely hispid above, the pubescence at first dense, becoming sparse with age, the trichomes 0.8-1.8 mm long, the leaves becoming shorter and more oblong-elliptic upwards and merging into the bracts of the inflorescence, venation somewhat obscure above; petioles indistinct, winged, the blades essentially sessile. Inflorescences several racemose-spicate branches, the nodes with ? elliptic, leaflike bracts to 3 cm long, generally 5-20 mm apart; clusters of heads subsessile, solitary in the axils, scorpioid, conical, to 15 mm high and 10 mm across, loose, few-headed, the individual heads overlapping but distinguishable; bracteoles oblong, to 2 cm long. Heads with 4 florets; involucral bracts 8, similar, in 4 decussate pairs, the outer pairs progressively shorter, the inner 2 pairs subequal, oblong-oblanceolate, boat-shaped, 8-10 mm long, 1.5-2.0 mm wide, mucronate, keeled, glabrescent, green towards the apex, hyaline basally, on the keel, and along the margins; corolla white or lavender, the tube slender, 5-6 mm long, the limb 3-4 mm long, deeply divided on the adaxial side, 5-cleft, the lobes ca. 2 mm long; anthers ca. 1.5 mm long, basally sagittate, the lobes ca. 0.15 mm long, the apical appendage rounded, ca. 0.16 mm long; style branches flattened and stigmatic adaxially, ca. 1.2 mm long, strigulose on the abaxial side of the branches and for ca. 0.4 mm on the shaft apex. Achenes narrowly obovoid, slightly flattened, 10-ribbed, 5.5-7 mm long, ca. 1 mm wide at the apex, tapered to the base, hispidulous principally on the ribs, the trichomes ca. 0.2 mm long, usually resin-dotted principally between the ribs; pappus in 1 series of 6-10 bristles, with the 2 lateral bristles longest, 4-6 mm long, gradually dilated to 0.3 mm wide at the base, and conspicuously doubly bent for about 1 mm, and with 2 abaxial bristles longer than the others, 3-5 mm long, generally straight, the remaining 1-3 pairs shorter and less conspicuous, the bristles generally lacerate at the base.
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