Publication: Bull. Torrey Bot. Club. 26: 314. 1899.
selected vouchers: WTU
Notes: Ortho spelling atrabarba Chambers and Sundberg (2000).
FNA19: "Crepis atribarba is generally recognized by the deeply pinnately lobed leaves with linear lobes, fine tomentulose indument on stems and leaves, setose phyllaries, and dark green, strongly ribbed cypselae. It is a variable mixture that includes polyploid, apomictic forms and hybrids with C. acuminata and other species. The typical form is recognized by its short stature, narrow pinnately lobed, tomentulose leaves, stems with 3–10 heads, and phyllaries with scattered, black, eglandular setae. Larger, more robust forms with stems 30–70 cm, 10–30+ heads, narrower involucres, and few or no black setae have been recognized as subsp. originalis. The latter was considered by E. B. Babcock (1947) to represent the original diploid form of the species; it is difficult to distinguish in practice."