Novon 13: 384. 2003.
Biennials; short-lived; sexual; caudex not evident. Stems 1 per plant, arising from center of rosette near ground surface, 2.5–10(–12.5) dm, sparsely to densely pubescent proximally, trichomes simple, to 1 mm, glabrous or sparsely pubescent distally. Basal leaves: blade obovate to oblanceolate, 10–30 mm wide, margins dentate, ciliate proximally, trichomes simple, to 1 mm, surfaces moderately pubescent, trichomes simple, 0.5–1.5 mm, these mixed with smaller, 2- or 3-rayed ones. Cauline leaves: 12–20, often concealing stem proximally; blade auricles absent or proximalmost blades with auricles 0.5–2(–5) mm, surfaces of distalmost leaves sparsely pubescent. Racemes 15–65(–82)-flowered, sometimes branched. Fruiting pedicels descending to horizontal, usually curved, rarely straight, 6–13(–17) mm, pubescent or glabrous, trichomes subappressed, usually 2-rayed. Flowers divaricate-ascending to horizontal at anthesis; sepals pubescent; petals white, 3–5 × 0.7–1.2 mm, glabrous; pollen ellipsoid. Fruits pendent to horizontal, not appressed to rachis, often secund, curved, edges parallel, 4–10 cm × 2.5–4 mm; valves glabrous; ovules 40–62 per ovary; style 0.3–0.8(–1.1) mm. Seeds uniseriate, 1.7–3.5 × 1.5–2.2 mm; wing continuous, 0.4–1 mm wide distally. 2n = 14.
Phenology: Flowering Apr–Jul.
Habitat: Bluffs, rocky slopes, ravines, open woods
Elevation: 0-1200 m
Que., Ala., Ark., Conn., D.C., Fla., Ga., Ill., Iowa, Kans., Ky., Maine, Md., Mass., Mich., Minn., Miss., Mo., Nebr., N.Y., N.C., Ohio, Okla., Pa., Tenn., Tex., Vt., Va., W.Va., Wis.