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..
Culms tufted, 12'-20' tall, pubescent below with long nearly appressed hairs, the upper portion glabrous or puberulent, finally branched, the nodes barbed with spreading hairs; sheaths, at least the lower ones, pubescent with long often appressed hairs; ligule 1/2 " long or more; blades 1 1/2'-4' long, 1 1/2"-4" wide, erect, lanceolate, appressed-pubescent on the lower surface with stiff hairs, the upper surface glabrous or with some long spreading hairs toward the base; panicle 1 1/2'-3' long, ovate, its branches spreading or ascending; spikelets 1 1/4" to a little less than 3" long and 1/2 as broad, obovoid, pubescent with spreading hairs, the first scale about i as long as the spikelet.
In dry sandy soil near the coast, Connecticut to North Carolina and Florida. June and July.
Panicum columbianum Scribn. Bull. U. S. Dept. Agric.
1899. P. columbianum var. thinium Hitchc. & Chase, Rhodora,
Culms tufted, erect, softly pubescent, 8'-2° tall, at length dichotomously branched, the branches erect. Lower sheaths pubescent, the upper glabrous, the primary one-half as long as the internodes; ligule a ring of short hairs; blades lanceolate, erect, thickish and firm, glabrous above, the lower ones more or less pubescent beneath, the primary 1 1/2'-2 1/2'Y long, 2"-3" wide, those on the branches smaller; panicle small, ovate, i'-1 1/2' long, its branches ascending; spikelets broadly obovate, a little more than 3/4" long, the outer 3 scales densely pubescent with spreading hairs, the first scale about one-half as long as the spikelet, 1-nerved, the second and third scales 7-nerved.
P. tsugetorum Nash, Bull. Torr. Club, 25: 86. 1898.
Culms and sheaths pubescent with short appressed or ascending hairs intermixed toward the base with longer ones. Culms tufted, 1 1/2° or less tall, somewhat slender, at length much branched and decumbent or prostrate; sheath shorter than the internodes; ligule a ring of hairs about i" long; blades erect or ascending, firm, lanceolate, 5-7-nerved, minutely appressed-pubescent beneath, smooth and glabrous above, or the upper primary leaves sometimes with a few long erect hairs, the primary leaves 1 1/2'-3' long, 2 1/2"-4" wide, those on the branches smaller and partly concealing the small panicles; primary panicles broadly ovate, 1 1/2'-2 1/2' long, the branches spreading-ascending; spikelets broadly obovate, about 7/8" long, the outer 3 scales pubescent, with short spreading hairs.
Dry soil in woods, Maine to Virginia, Illinois and Tennessee.