Plants 30-120+ cm; rootstocks short, stout; herbage loosely tomentose when young, glabrescent, sometimes ± glandular. Stems 1-many, leafy, simple or with ascending branches. Leaves cauline, usually more than 20, well distributed, proximal and mid with winged petioles to 6 cm, wings sometimes decurrent 1-2 cm on stems, blades lanceolate to triangular-ovate, 5-15 cm, bases cordate to truncate or tapering, margins sharply dentate, apices acute; mid and distal usually sessile, smaller, narrower, bases tapering. Heads 5-30+ in tight to open corymbiform arrays; (peduncles 0-5 cm). Involucres 10-15 mm. Phyllaries in ca. 5 series, strongly unequal, outer ± ovate, inner lanceolate, abaxial faces pale green, distally dark purplish to nearly black, loosely tomentose. Receptacles naked. Florets 8-21; corollas usually pale lavender-blue to dark purple (rarely white), 11-13 mm; tubes 5-6.5 mm, throats 1.5-2 mm, lobes 3.5-4 mm. Cypselae 4-6 mm; pappus bristles brownish, outer 3-7 mm, inner 9-10 mm.

Flowering Jul-Aug. Moist canyons, meadows, streamsides in montane forests; 1000-2600 m; Alta., B.C., Yukon; Alaska, Calif., Idaho, Mont., Oreg., Wash.

Saussurea americana is closely related to an Asian species, S. foliosa Ledebour.