HOW TO KNOW THE GRASSES 



TRIBE XII. ANDROPOGONEAE 



la. Both spikelets of each pair on stalks 2 



lb. One spikelet of each pair sessile 4 



2a. Racemes single on each peduncle; awns hairy lib 



2b. Racemes several to many on each peduncle; awns absent or 

 smooth 3 



3a. Inflorescence narrow, spikelike; spikelets awnless. Fig. 338. 



SATINTAIL Iznperata bTeviiolia Vasey 



Perennial; culms arising from hard scaly 

 rhizomes; culms 1 — 1.5 m. tall, with elongated 

 leaves and slender, silvery-hairy panicles, 15 

 — 35 cm. long and 1 — 3 cm. thick. The spike- 

 lets are about 3 mm. long and have a ring 

 of long white hairs at the base, with some 

 hairs also attached to the backs of the 

 glumes. The spikelets fall from the rachis 

 when ripe. Deserts. July — September. 



Imperata cylindrica (L.) Beauv. (COGON 

 GRASS) has been introduced in western Flori- 

 da. Spikelets 4 — 5 mm. long. This species 

 has forage uses but may become a weed, 

 Figure 338 because of its extensive rhizomes. 



3b. Inflorescence fan-shaped; spikelets with awns. Fig. 339. 



EULALIA Miscanthus sinensis Anderss. 



Perennial, forming large clumps; culms 

 2 — 3 m. tall, with plumeHke, silvery-gray, 

 fan-shaped panicles of long, hairy racemes. 

 The spikelets are about 5 mm. long, with 

 a ring of hairs about as long as the spike- 

 let, attached at the base of the glumes. 

 The spikelets fall from the rachis when 

 ripe. Cultivated widely as an ornamental, 

 and escaping to the wild occasionally 

 around inhabited places. Horticultural 

 forms with white striped or cross-banded 

 leaves are also grown. September — Oc- 

 tober. Native to Asia. 



Figure 339 



176 



