Rhodora 77: 49. 1975.
Perennials, to 300 cm (rhizomatous, roots fibrous). Leaves green, oblong to elliptic or ovate to pandurate, herbaceous, margins crenate, dentate, entire or serrate, apices acute, faces scabrous, abaxial often glabrescent; basal petiolate, 20–65 × 8–20 cm, bases attenuate; cauline sessile, 15–40 × 4–15 cm, bases auriculate to truncate. Heads (usually 10+) in paniculiform arrays. Phyllaries to 1 cm. Receptacles conic to ovoid; paleae 4–6 mm, apices obtuse to acute, abaxial tips hairy. Ray-florets 8–14; laminae oblanceolate, 18–30 × 4–8 mm, abaxially sparsely hairy. Discs 12–16 × 10–18 mm. Disc-florets 150–200; corollas brown-purple, 3.5–4.2 mm; anther appendages glabrous or glanddotted; style-branches to ca. 1.8 mm, apices acute to obtuse. Cypselae 3.5–5 mm; pappi of 4–6, unequal scales, to 2 mm. 2n = 36.
Phenology: Flowering summer–fall.
Habitat: Sandy stream banks, wet roadsides
Elevation: 10–90 m
Ala., Fla., Ga.
Of conservation concern.
Rudbeckia auriculata is known from eight sites in Alabama, one in Florida, and one in Georgia.