There has been confusion involving the names purpurascens, affinis, virgata and palustris (FNA 25). A. affinis (J.A. Schultes) Kunth is not considered distinct from typical purpurascens in some recent treatments. A. virgata has often been treated as a southern variety, but may warrant species status (W). A. palustris (Chapman) Vasey ("affinis" misapplied) is restricted to the Coastal Plain and unknown in Ky. or Tenn. Colls. from LAUR (US) and PULA (KY, BEREA) have been called affinis, virgata or palustris, but do not exactly match any of those taxa. They have awns that do not diverge as much as typical purpurascens, and might be transitional from purpurascens to virgata. C.W. Short's (CINC) coll. under "palustris" from "barrens of Ky." still needs to be checked (M).