HOW TO KNOW THE GRASSES 



10b. Plants perennial, with hard, knotty crowns; leaf blades usually 

 folded, 15 — 40 cm. long; panicles slender, 2 — 25 cm. long, with 

 sparse bristles. Fig. 291. 



PLAINS FOXTAIL Setaria macTosiachya H. B. K. 



Perennial; in hard tufts; culms 40 — 120 

 cm. tall; panicles slender, with the hairy 

 rachis exposed between clusters of spike- 

 lets. The plants are leafy and are highly 

 palatable to livestock, so that they are 

 usually kept grazed down except in climips 

 of spiny bushes. Dry plains and savan- 

 nas, especially along roadsides or other 

 areas protected from grazing. April — 

 October. 



Figure 291 



11a. Spikelets covered with long, silky, white or brownish or rosy 

 purple hairs 12 



lib. Spikelets smooth or hairy with short hairs, or silky on the mar- 

 gins only 13 



12a. Spikelets laterally compressed; second glume and sterile lemma 

 awned; hairs rosy purple. Fig. 292. 

 NATAL GRASS; RUBY GRASS 



RhynchelytTum roseum (Nees) Stopf & Hubb. 



Perennial; tufted; plants about 1 m. 

 tall; panicles rosy-purple, 10 — 15 .cm. 

 long; spikelets on bent or curled pedi- 

 cels, and densely covered with purple 

 hairs. The second glume and sterile 

 lemma have short awns, which are con- 

 cealed by the hairs. The lateral com- 

 pression of the spikelets is very atypical 

 for the Panicoideae. Dry sandy land 

 and open woods. Natal Grass, an in- 

 troduction from Africa, is grown in Flori- 

 da for forage and has become natural- 

 ized there and also along the Gulf Coast. 

 Winter. Formerly known as Tricholaena 

 rosea. 



Figure 292 



154 



