42 Bulletin VII. 1. 



ceous, very short; leaf blade linear, six to twenty-four inches long, 

 more or less carinately f >lded near the base, scabrous. Panicle 

 four to ten inches long, terminating the culm and its branches, the 

 uppermost usually double by an erect branch from the upper leaf- 

 axil, pyramidal, the scabrous primary branches ascending, widely 

 spreading or even reflexed, the secondary branches usually 

 appressed, pedicels as long as, or more often much shorter than 

 the spikelets, scabrous, and frequently bearing a few long hairs. 

 Spikelets one to one and one-fourth lines long, racemose,* scattered 

 or much crowded along one side of the branches, lanceolate or 

 ovate, acute; first glume three-nerved, acute, scabrous on the keel 

 above, about one-half as long as the equal five-nerved second and 

 third glumes; third glume has a thin palea which is ciliate on the 

 margins near the apex; fourth glume hard and shining, elliptical 

 or narrowly obovate, one-half to three-fourths of a line long, 

 nearly sessile or raised on a distinct pedicel, apex barbulate with 

 a few short hairs. 



Var. elon^ituni [P. elonvntuju Pursh). Plate IX. Figure 34. Panicle 

 rather loosely flowered; spikelets one and a half lines long, sub- 

 acuminate pointed, fertile floret distinctly pedicellate. This is the 

 more common form in East Tennessee. It grows along the banks 

 of streams and in wet meadows, often affording a considerable 

 amount of fairly good native hay. In low, moist and rather rich 

 soils Its cultivation may prove profitable. 



9. Panicum virgatum L. Switch-grass. 



Plate IX. Figure 35. 



A stout, erect perennial three to five feet high, with strong creep- 

 ing rootstocks, long, flat leaves and ample spreading panicle. 

 Culms smooth, terete. Sheaths smooth, ciliate along the margins 

 -above; ligule very short, naked, or densely and long pilose; leaf- 

 blade ten to twenty-four inches long, two to five lines wide, scab- 

 rous on the margins, sometimes pilose above near the base, other- 

 wise smooth, long-acuminate pointed. Panicle six to twenty 

 inches long, the branches solitary, or several together, more or 

 less widely spreading, rather rigid, the lower four to ten inches 

 loni. Spikelets ovate, acuminate, two to two and one-half lines 

 long; the acuminate first glume about one-half the length of the 

 spikelet, three- to five-nerved; second glume usually longer than 

 the others, five- to seven-nerved, as is the third, which has a palea 

 and usually a staminate flower in its axil; flowering glume smooth 

 and shining, distinctly shorter than the larger outer glumes. 



Sandy soil, August to October. Gattinger records P. virgatum as 

 growing in moist sandy soil along the Cumberland river and on 

 the highlands and barrens at TuUahoma. When young this grass 

 affords good grazing, but by the time it blooms the stems become 

 hard and practically worthless for fodder. Its cultivation here can- 

 not at present be recommended. It has grown finely in the ex- 

 perimental plots at the Experiment Station, and during the latter 

 part of May the leafage of this grass is large and decidedly at- 

 tractive to the farmer. 



