238 A TEXT-BOOK OF GRASSES 
guished from Triticum by the narrow pointed or awned 
glumes. The American species are perennials. Couch- 
grass, A. repens (L.) Beauv. (Fig. 58), is a troublesome 
ih weed introduced from Europe. It prop- 
y agates by creeping rhizomes. A similar 
Vy 4 native species, A. Smithii Rydb., is found 
in alkali soil in the western states and 
furnishes a fair quality of hay. Another 
species, A. tenereum Vasey, is a bunch-grass 
of the same region. This species has been 
introduced into cultivation and is sold by 
seedsmen under the name of slender wheat- 
grass. This has erect stems 2 to 4 feet 
high, with slender spikes 2 to 6 inches 
long, or even longer, broad-nerved awn- 
pointed glumes nearly as long as the spike- 
let, and short-awned or awnless lemmas. 
263. Triticum L.— Wheat. A _ small 
genus of annuals distinguished from Agro- 
pyron by the broad several-toothed or 
awned glumes. The best known species is 
the common wheat (7’. vulgaris; T. sativum) 
of which there are numerous varieties. 
Those varieties bearing long awns are 
called bearded wheais; those in which the 
awn is short or none are called beardless 
Fig. 58. Agropyron repens. Inflorescence and 
rhizomes, X %; spikelet, <3. 
