Publication: in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 5: 284 1836.
selected vouchers: WTU
Notes: Taxonomy follows Flora of North America not recognizing varieties; FNA 20 (Nesom): "Plants glabrous and glandular on the phyllaries, stems, and leaves have been recognized as var. macranthus; they intergrade with hairier forms and do not show a coherent geographic pattern."