The alien or native status of this widespread variable northern (circumboreal) species in Ky. is somewhat unclear; 2n = 28-70. Also, there has been confusion with trachyphylla and ovina. In Ky. "rubra" has been widely sown for forage and turf since before 1900, when Gm noted that its seed was as almost as highly priced (at 20 cents per pound) as arundinacea (as "elatior"). Colls. from BULL, MCRE (KY) and elsewhere may be from plantings. However, colls. from CUMB and FRAN (KY) in clifftop woods (and similar habitat in Clay Co., Tenn.) appear to be native or thoroughly naturalized. There may also be a ca. 1830 coll. of C.W. Short from "Ky Rv cliffs, hanging over rocky precipice" (originally filed under F. duriuscula at PH). F and Cr stated that rubra appears native in more northern and coastal regions; see also ssp. pruinosa (Hack.) Piper in FNA 24. F. rubra is distinguished from trachyphylla and ovina by its more rhizomatous habit and deeper green leaves (versus pale bluish); its sheaths are closed for at least 3/4 of their length (versus less than 2/3), usually retrose-hairy (versus glabrous), and older ones shred into fibers (versus persistent for several years without much shredding). Also, its spikelets tend to be larger (mostly 7-17 mm long versus 5-9 mm); see FNA 24 for details.