Panicum longifolium Torr.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Species Description - Tufted perennial to 1 m; culms much compressed; sheaths compressed, glabrous or villous; ligule a row of fine hairs 1–3 mm; blades to 3 dm, no wider than the sheaths; panicle usually 1–2 dm, its branches spreading to subappressed; spikelets lance-ovoid, green or purple-tinged, 2–3.5 mm; first glume half to three-fourths as long as the spikelet; second glume and sterile lemma subequal, acuminate; 2n=18. Moist or wet soil, open woods, bogs, and pond-margins, seldom in dry soil, mainly on the coastal plain; N.S.; e. Mass. to Fla., Ark., and Tex.; Ky. (P. combsii)