HOW TO KNOW THE GRASSES 



14a. Rachis of spikes not breaking up when ripe 15 



14b. Rachis oi spikes breaking up into individual joints, each bearing 

 2 spikelets, when ripe. Fig. 172. 



SQUIRRELTAIL Sitanion hystrix (Nutt.) J. G. Smith 



Perennial; tufted; culms 10 — 50 

 cm. tall, erect or spreading. The 

 glumes bear one or two long, bent 

 awns. The plants resemble Horde- 

 um jubatum but the several florets 

 per spikelet and two spikelets per 

 node separate it from that spe- 

 cies. The rachis joints bearing 

 the awned spikelets, may pene- 

 trate the facial parts of grazing 

 animals, causing serious inflam- 

 mation, pink eye, etc. Fair forage when seed heads are not present. 

 Dry woods and grasslands. April — September. 



Sitanion jubatum J. G. Smith is similar but has three or more awns 

 on each glume. Intermoimtain and Pacific Coast States. 



Figure 172 



15a. Plants lacking rhizomes or rarely with short, thick ones. 



15b. Plants producing slender creeping rhizomes; lig\ile 1 

 Fig. 173. 



16 



mm. long. 

 Elyznus triiicoides Buckl. 



Perennial; culms usually 60 — 120 cm. tall, 

 single or in small tufts, forming large 

 patches by means of the long, slender 

 rhizomes. The leaves are harsh, stiff, blu- 

 ish-glaucous and often rolled. Damp or 

 sahne soils, open ground. Sometimes part 

 of the spike will have only a single spike- 

 let at a node. Seven other species of 

 Elymus produce extensive rhizomes. They 

 are mostly plants of sand dunes along the 

 oceans or in river valleys. May — August. 



Figure 173 



92 



