Family: Poaceae
[Agropyron flexuosum (Piper) Piper, more..., Agropyron saxicola (Scribn. & J.G. Sm.) Piper, Agropyron sitanioides J.G. Sm., Agropyron x saxicola (Scribner & J.G. Smith) Piper (pro sp.), Elymus saxicola Scribn. & J.G. Sm., Elymus x saxicola Scribn. & J.G.Sm., Sitanion flexuosum Piper, Sitanion lanceolatum J.G. Sm., x Agrositanion saxicola (Scribn. & J.G. Sm.) Bowden]
Hitchcock, A.S. (rev. A. Chase).