Rudbeckia scabrifolia

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.

Flowering late spring-fall. Hillside seeps; 10-60 m; La., Tex.

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