HOW TO KNOW THE GRASSES 



lib. Rachis of spikes not separating into joints; cultivated annual. 

 Fig. 168. 



BARLEY Horde um vuJgare L. 



Annual; tufted; culms usually 60 — 120 cm. tall; leaf 

 blades flat, usually 5 — 15 mm. wide, with prominent 

 auricles; spikes stiff and erect; spikelets 3 at each 

 node of the rachis; each spikelet with a single fertile 

 floret; glumes owned; lemma with a stout awn, usually 

 10 — 15 cm. long and very scabrous; rachilla pro- 

 longed behind the palea as a small bristle. In the 

 hooded barleys, the lemmas lack owns but bear min- 

 ute abortive extra lemmas at their tips, in inverted 

 position. Common strains of barley are 6-rowed, that 

 is, all 3 spikelets at each node develop grains. There 

 are also 2-rowed barleys, in which only the central 

 spikelet of each trio develops a grain. Barley is cul- 

 tivated for the grain, which is used for human food 

 (pearl barley, cereals), for production of malt, and 

 for livestock feed. It is grown principally in the 

 Middle West and in the Great Valley of California. 

 Stray plants may grow from scattered seed, but bar- 

 ley is never found growing as a truly wild plant. 



Figure 1 68 



12a. Awns mostly 5 — 8 cm. long; plants perennial. Fig. 169. 



FOXTAIL BARLEY Hordeum jubatum L. 



Figure- 169 



Tufted; culms 30—60 cm. tall. 

 The bushy spikes are 5 — 10 cm. 

 long, and because of the spread- 

 ing awns, about as wide. When 

 still fresh, the awns often have a 

 purplish or pink sheen . When 

 the spikes are ripe, they break 

 up into segments, each with a 

 sharp-edged rachis joint at its 

 base, and a trio of spikelets at 

 its apex. Only the central spike- 

 let is fertile, and the lateral two 

 are reduced to long awns. The 

 spike-segments are able to pene- 

 trate clothing, wool, or flesh, 

 causing puncture wounds, espe- 



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