INDIAN GRASS. 149 



Purple Wood Grass, Broom Grass {Andropogon 

 scoparius), is found on sterile, sandy soils, flowering 

 from July to September. It , grows from two to four 

 feet high, with many-branched panicles ; lower sheaths 

 and narrow leaves hairy; spikes mostly single, very loose, 

 slender, slightly silky, with dull, white hairs ; rachis zig- 

 zag, hairy along the edges. 



Silver Beard Grass {Andropogon argenteus) grows 

 about three feet high, with spikes in pairs, on peduncles 

 exceeding the sheaths, dense, and ver}-^ silky. Common 

 on sterile, sandy soils, in Virginia and southward, flow- 

 ering in September and October. 



Virginian Beard Grass {Andropogon Virginicus) 

 grows on similar soils to the last, from New York to 

 Illinois, and southward. Stem flattish below ; slender, 

 short-branched above; sheaths smooth; spikes soft, 

 two or three in distant clusters. 



Cluster-flowered Beard Grass {Andropogon met- 

 crourus) is found from New York to Virginia, south- 

 ward on the coast. Stems from two to three feet high, 

 bushy, branched at the summit, with many spikes, form- 

 ing thick, leafy clusters ; sheaths rough, the upper 

 hairy. 



65. Sorghum. 



Spikelets two or three together, in an open panicle, 

 the lateral ones sterile, middle fertile ; stamens three. 



Indian Grass, Wood Grass {Sorghum nutans), is, a 

 grass sometimes found on our dry, sterile soils, with a 

 panicle oblong, somewhat compressed, from six to ten 

 inches long ; stem from three to five feet high ; leaves 

 linear, grayish ; sheaths smooth ; spikelets light brown 

 and glossy, drooping when mature ; hairy at the base ; 

 awn twisted. It flowers in August. 

 13* 



