"Much like no. 4 [Cirsium pumilum (Nutt.) Spreng], but perennial with long, thickened roots, these traversed longitudinally by several cavities; glutinous dorsal ridge of the invol bracts avg larger and better developed; achenes mostly 4–5 mm; 2n=30. Prairies and other open places, often in sandy soil; s. Ont. to Pa., w. to Minn. and S.D. June–Aug."