Tall, erect perennial, 1-2.5 m high; culms stout, glabrous but with bearded nodes. Sheaths mostly shorter than the internodes, papillose-hirsute becoming glabrous; ligules truncate and erose with dense cilia behind the ligule 4-5 times as long as the ligule, 3-4 mm long; blades to 70 cm long and 3 cm wide, glabrous to sparsely hispid with scabrous trichomes. Inflorescence a diffuse terminal panicle 20-45 cm long; branches slender, scabrid; spikelets long-pedicellate, 2.7-3.7 mm long, glabrous; first glume one-fourth to one-third as long as spikelet; second glume and sterile lemma nearly equal to each other and exceeding fruit. Fruits ca 2.7 mm long, greenish-white, transversely rugose. Croat 6001, 11990. Common locally at the Laboratory Clearing along the stairs from the dock and in the Lighthouse Clearing. One of the most abundant roadside and pasture grasses in the isthmus.