Stems erect or ascending, stout, 10-150 cm. Leaf faces glabrous or nearly so or abaxial ± villous with septate trichomes. Heads several-many, usually subsessile or short-pedunculate, crowded in erect. spiciform or racemiform arrays, less commonly openly branched. Involucres 2-4 cm, loosely to densely villous with septate trichomes and thinly arachnoid with non-septate trichomes. Phyllaries green; outer with few or no lateral spines; apical spines stout. Corollas pink to purple, 21-25 mm, tubes 6.5-8 mm, throats 8-11.5 mm, lobes 5.5-7 mm. Pappi 17-22 mm. 2n = 34 (as C. peckii). Flowering summer (Jun-Aug). Grasslands, juniper woodlands, grass-sagebrush steppes, subalpine slopes, roadsides; 1300-2900 m; Nev., Oreg. Variety peckii occurs from Steens Mountain and the Pueblo Mountains of Harney County, Oregon, south to the Black Rock Range and Jackson Mountains of Humboldt County, Nevada. On the lower portion of its distribution along Steens Mountain Loop Road at an elevation of about 1900 m, var. peckii and Cirsium inamoenum grow together and freely hybridize, forming a complex hybrid swarm. Intermediates variably combine the features of the parent taxa, with the habit more openly branched than typical for C. eatonii var. peckii, variably arachnoid tomentose leaves, ± glandular phyllaries, and lavender to pale pink flowers. Variety peckii may range as far south as the West Humboldt Mountains. The type of Cirsium humboldtense Rydberg (Carduus nevadensis Greene) closely resembles some of the hybrids between C. inamoenum and C. eatonii var. peckii.