Pterocaulon virgatum (L.) Dc.

Erect herb to 1 m tall; stems prominently winged by linear, discolorous leaf-bases; rootstock thick and woody with a black surface. Leaves mostly 6-8 cm long, smaller and narrower near the inflorescence, lanceolate to elliptic, entire or crenate, apically obtuse, basally narrowed at the juncture with the stem, beneath tomentose with buff, cobwebby or crinkled, simple hairs, above glabrate, the principal veins pubescent. Inflorescence to 12 cm long and 5 cm across, a terminal, unbranched spike, congested or open, the peduncle not evident, the heads sessile in glomerules or solitary with linear bracts approaching or subtending the glomerules. Heads disciform, to 1 cm long; involucral bracts imbricate in several unequal series, acute, tomentose outside, 2-3 mm long, the midrib prominent; ray florets numerous, ca. 10 mm long, the corolla capillary, apically 4-denticulate, slightly expanded at the base, the style branches slender, slightly exserted, the style base hemispherical, the ovary cylindrical, densely hirsute with ascending hairs; disc florets several, 7-8 mm long, the corolla tubular, 6-7 mm long, apically irregularly 5-lobed, the lobes ca. 1 mm long, the anthers ca. 1 mm long, the appendages blunt, the basal auricles connate with filiform, short, crumpled tails, the style branches lanceolate, dorsally puberulent, the style base expanded, situated on a thickened conical stipe, the ovary rudimentary, pubescent with weak spreading hairs. Achene orange-brown, ca. 1 mm long, plump, with prominent, straminous ribs, hirsute with ascending hairs, glandular; pappus white to stramineous, of numerous slender bristles 8-11 mm long in 1 series.