Cacalia plantaginea (Rafinesque) Shinners; C. pteranthes Rafinesque; C. tuberosa Nuttall; Conophora tuberosa (Nuttall) Nieuwland; Mesadenia plantaginea (Rafinewque)Rafinesque; M. tuberosa (Nuttall) Britton; Senecio nuttallii Schultz-Bipontinus

Plants 50–100 cm (weakly rhizomatous). Stems angulate. Basal leaves: blades broadly elliptic, to 17 cm, margins entire or sinuate. Cauline leaves: proximal (and mid) petiolate, elliptic (bases rounded), margins entire or serrulate; distal petiolate or sessile, smaller (narrower). Involucres (9.5–)10–12(–14) mm. Phyllaries (pale green) ovate, midvein wings uniform or highest at apices. Corollas white or greenish, 8–10(–11.5) mm. Cypselae fusiform or clavate, 4–5 mm (dark brown, 12–15-ribbed); pappi (6–)7–8(–9) mm. 2n = 54.

Flowering May (south)–Aug (north). Wet prairies and pastures, usually in boggy areas in north; 0–600 m; Ont.; Ala., Ark., Ill., Ind., Iowa, Kans., Ky., La., Mich., Minn., Miss., Mo., Nebr., Ohio, Okla., S.Dak., Tenn., Tex., Wis.