Perennials, 150-350 cm (rhi-zomatous). Stems erect, glabrous (glaucous). Leaves mostly cauline; mostly alternate; petioles 0-3 cm; blades (light to dark green, 3-nerved distal to bases), lanceolate, 10-20 × 2.5-6 cm, bases ± cuneate, margins entire or subentire, abaxial faces hispid to hirsute, gland-dotted. Heads 3-10. Peduncles (1-)3-15 cm (gland-dotted). Involucres broadly hemispheric, 10-25 mm diam. Phyllaries 25-35 (loose ), lanceolate, 8-15 × 3-5 mm (notably surpassing discs), (margins sometimes ciliate) apices acute to attenuate, abaxial faces hispidulous to glabrate, gland-dotted. Paleae 10-11 mm, 3-toothed (apices acute, hispidulous). Ray florets 12-21; laminae 15-30 mm. Disc florets 50+; corollas 6-8 mm, lobes yellow; anthers reddish to dark, appendages reddish brown. Cypselae 4.5-5 mm, glabrate; pappi of 2 aristate scales 3-4 mm. 2n = 102.

Flowering summer-fall. Stream banks, wet meadows, freshwater marshes; to 1600 m; Calif.; Mexico (Baja California).