This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol1", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Perennial grasses with flat and usually short rigid leaf-blades and numerous slender alternate spikes. Spikelets 1-flowered, almost sessile, the rachilla extended and bearing a small scale which is usually awned. Scales 3 or 4; the 2 lower empty, unequal, narrow, acute; third broader, fertile, 3-nerved, slightly 2-toothed at the apex, bearing an erect awn; the fourth empty, small, awned; palet 2-keeled. Stamens 3. Styles distinct. Stigmas plumose. Grain linear, free, enclosed in the rigid scale. [Greek, naked-beard, referring to the prolongation of the rachilla.]
Spikes bearing spikelets their whole length; awn longer than flowering scale.
Spikes bearing spikelets above the middle; awn shorter than flowering scale.
Culms 12'-18' tall, erect, or decumbent at the base, simple or sometimes sparingly branched, smooth and glabrous. Sheaths short, glabrous, excepting a villous ring at the summit, crowded at the base of the culm; ligule very short; blades 1'-4' long, 2"-6" wide, lanceolate, acute, cordate at the base, spreading, smooth or a little scabrous above; spikes slender, spikelet-bearing throughout their entire length, at first erect, the lower 4'-8' long, at length widely spreading; spikelets, exclusive of awns, 2"-2 1/2" long; first scale snorter than the second; third scale exceeded by the second, the callus at the base hairy, the awn 2"-3" long.
In dry sandy soil, southern New Jersey to Kansas, south to Florida and Texas. Aug.-Oct.
Gymnopogon brevifolius Trin. Unifl. 238. 1824.
Culms 1°-2° long, from a decumbent base, simple, slender, smooth and glabrous. Sheaths shorter than the internodes, sometimes crowded near the middle of the culm; ligule very short; blades 1'-2' long, 1"-4" wide, usually spreading, lanceolate, acute, cordate at the base; spikes very slender, spikelet-bearing above the middle, the lower 4'-6' long, at first erect, finally widely spreading; spikelets, exclusive of the awns, 1 1/2" long; first scale shorter than the second; third scale equalling or exceeded by the second, short-awned, sparingly villous or glabrous, the callus hairy.
In dry soil, New Jersey to Florida, west to Mississippi. Aug.-Oct.