Roughleaf Coneflower

Rudbeckia scabrifolia occurs in western Louisiana and eastern Texas. It is in the Center for Plant Conservation’s National Collection of Endangered Plants.

Perennials, to 200 cm (rhizomatous, roots fibrous). Leaves green (dried, dark under reflected UV light), blades elliptic to lanceolate (not lobed), ± leathery, bases attenuate to cuneate or rounded, margins entire or coarsely toothed, apices acute, faces hairy; basal petiolate, 15–65 × 2–15 cm; cauline sessile (proximalmost often petiolate), 5–50 × 2–12 cm (mids ± pandurate, bases auriculate). Heads (to 15) in ± corymbiform arrays. Phyllaries to 2 cm (margins ciliate). Receptacles ovoid to ellipsoid; paleae 6–8 mm, (apical margins densely ciliate) apices acute, abaxial tips hairy. Ray florets 10–15; corollas yellow, laminae oblong to oblanceolate, 20–40 × 5–12 mm, abaxially hairy. Discs 12–25 × 12–20 mm. Disc florets 150–400+; corollas greenish yellow proximally, maroon distally, 3.5–5 mm; style branches ca. 2 mm, apices acute. Cypselae 3.5–5 mm; pappi coroniform, to 2.5 mm. 2n = 36.