Coarse perennial herbs to 3 m tall, unbranched or branching from base; stems greenish or pale brownish, mostly hexagonal, slightly striate, rather densely minutely puberulous. Leaves usually laxly imbricate, opposite, narrowly elliptical to lanceolate, to 25 cm long and 7 cm wide, the base petioliform with narrow wing, auriculate at base, becoming wider and indistinct above, the margins entire to serrulate, sometimes somewhat crenate-serrate below the middle, the apex narrowly and sharply acuminate, the upper surface glabrate with sparse small hairs, the lower surface glandular-punctate and puberulous with short hairs, the venation pinnate with secondary veins ascending. Inflorescence paniculate with laxly subcymose branches, the ultimate branches mostly 3-7 mm long, densely puberulous. Heads ca. 5 mm high with 20-25 florets; involucral bracts ca. 25, subimbricate, in ca. 3 series, 1.0-4.5 mm long, ovate to oblong with broadly scarious margins, the apex rounded to obtusely acute, the outer surface with few glandular punctations, puberulous on exposed parts; corolla white to greenish, ca. 3 mm long, narrowly funnelform, glabrate, the lobes ca. 0.2 mm long and wide, densely glanduliferous on outer surface. Achenes ca. 1.5 mm long, with numerous bristles mostly on the ribs; pappus of ca. 35 slender bristles.
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