Sorrie, B.A. 2018b. Panicum virgatum var. spissum (Poaceae) in the southeastern United States. Pp. 61-62. In Weakley, A.S., D.B. Poindexter, R.J. LeBlond, B.A. Sorrie, E.L. Bridges, S.L. Orzell, A.R. Franck, M. Schori, B.R. Keener, A.R. Diamond, Jr., A.J. Floden, and R.D. Noyes. 2018a. New combinations, rank changes, and nomenclatural and taxonomic comments in the vascular flora of the southeastern United States. III. J. Bot. Res. Inst. Texas 12: 27-67.