Plants herbs, erect to spreading, 3–8 (10) dm tall, 0.5–1.5 dm across, glabrous and glaucous, rarely tomentose, greenish; stems spreading to erect, without persistent leaf bases, up to 1/3 height of plant, the caudex stems absent, the aerial flowering stems erect to spreading, slender to stout, solid or hollow, often fistulose, 1–3 dm long, glabrous, rarely tomentose; leaves basal, 1 per node, the petioles 3–8 (10) cm long, tomentose to floccose, leaf blades oblong-ovate to ovate, 2–4.5 cm long, 0.5–2.5 cm wide, lanate to densely or sparsely tomentose abaxially, thinly floccose or glabrous and green adaxially, the margins plane; inflorescences narrowly virgate or racemose with involucres racemosely disposed throughout or at tips, 20–45 (60) cm long, 5–25 cm wide, glabrous, rarely tomentose, the branches dichotomous, upper secondaries suppressed and bearing (8) 10–15 (30) racemosely arranged involucres, the bracts 3, scalelike, triangular, and 2–7 mm long, or foliaceous, linear-oblanceolate or oblanceolate to elliptic, and 10–40 mm long, 5–25 mm wide; peduncles absent; involucres 1 per node, turbinate to turbinate-campanulate, 1.5–3 mm long, 1.5–2.5 mm wide, tomentose to nearly glabrous, the teeth 5, erect, 0.2–0.5 mm long; flowers 2–6 (7) mm long, the perianth white or yellowish, glabrous, the hypanthium 1⁄4 their length of perianth, the tepals monomorphic, oblong, the stamens exserted, 2–5 mm long, the filaments pilose proximally; achenes light brown, (3) 4–5 (6) mm long, glabrous. 2n = 40.
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