Carex rugosperma Mackenzie. Section: [26bbb] Section 39 Acrocystis. Phen: Apr-Jun. Hab: Old fields, shallow soils of rock outcrops, exposed forest margins. Dist: PE west to MN, south to GA, TN, IN, IL, and MO. Reported for South Carolina by Hill & Horn (1997).
Origin/Endemic status: Native
Taxonomy Comments: See C. umbellata for discussion.
Synonymy: = G, Il, K4, NY, Va, Mackenzie (1931-1935); = Carex tonsa (Fernald) E.P.Bicknell var. rugosperma (Mack.) Crins – FNA23, K1, K3, Mi, NE, Pa; = Carex umbellata Schkuhr ex Willd. – F, misapplied; < Carex umbellata Schkuhr ex Willd. – C, RAB, W