Perennials, 70-150 cm (rhi-zomatous). Stems (usually purplish) erect, glabrous (glaucous). Leaves cauline; opposite (proximal) or alternate; petioles to 1.3 cm; blades (light to dark green, 1-nerved) lance-linear to lanceolate, 7-18 × 1-1.8 cm, bases ± cuneate, margins serrulate, abaxial faces ± hispid, gland-dotted. Heads 1-5. Peduncles 3-6 cm. Involucres hemispheric, 5-15 mm diam. Phyllaries 15-20, lanceolate, 6-9 × 2-2.7 mm, (margins ciliate) apices short-acuminate, abaxial faces glabrous or glabrate, not gland-dotted. Paleae 5.5-6.5 mm, 3-toothed (gland-dotted). Ray florets 6-9; laminae 10-15 mm. Disc florets 25+; corollas 5.5-6 mm, lobes yellow; anthers dark, appendages dark. Cypselae 2.8-3 mm, glabrate; pappi of 2 aristate scales 1.5-2 mm. 2n = 68.

Flowering late summer-fall. Dry, open woods; of conservation concern; 100-300+ m; Ala., Ga., Tenn.

Helianthus smithii is known from relatively few sites. T. A. Storbeck (1984) concluded that it is a distinct species; he could not rule out the possibility that it might be a hybrid of H. microcephalus and H. strumosus. It may also be an extreme variant of H. strumosus that has relatively narrow leaves and small heads.