Perennials, 15-60 cm (taproots slender, caudices swollen). Stems 1-3, slender or stout, branched proximally (sparingly) or distally, glabrate to tomentulose. Leaves basal and cauline; petiolate (petioles relatively broadly winged); blades elliptic or oblanceolate, often runcinate, 7-28 × 0.5-7 cm, margins pinnately lobed to dentate (lobes remote, lanceolate to narrowly triangular, often recurved), apices attenuate, faces usually tomentulose to glabrate, sometimes glandular. Heads 7-10(-30), in corymbiform arrays. Calyculi of 5-6, deltate to lanceolate, tomentulose bractlets 1.5-4 mm. Involucres cylindro-campanulate, 8-16 × 3-5 mm. Phyllaries 5(-10), (deep green or black) lanceolate, 10-16 mm, (bases becoming strongly keeled and swollen, often glabrous, margins yellowish, conspicuously and densely tomentulose), apices acute to strongly acuminate, abaxial faces densely tomentulose adaxial with fine hairs. Florets 5-10(-12); corollas yellow, 15-20 mm. Cypselae deep reddish brown, subcylindric, 5-8 mm, apices constricted, ribs 10 (prominent); pappi yellowish white, 6-12 mm (bristles unequal). 2n = 22, 33, 44, 55, 77, 88. Flowering Jun-Aug. Streams in mixed conifer forests, road cuts, steep rocky serpentine slopes; 400-2200 m; Calif., Idaho, Nev., Oreg., Wash. Crepis pleurocarpa is distinguished by its narrow, acuminate, silvery leaves, 5(-10), strongly keeled phyllaries with conspicuous white, tomentose margins, strongly ribbed cypselae, and relatively few florets per head. Otherwise, it is very similar to C. acuminata and C. intermedia.