GRASSES, GRAINS, AND PLANTS. 553 



Several species of Andropogon are diffused from Arizona to 

 British America, but are not found on the western coast. The 

 principal species are Andropogon scoparius, A. furcatus, and A. 

 (Chrysopogoii) nutans. Some of them are known under the 

 name of "blue-joint." 



Other grasses, also widely spread, but in more sparing quan- 

 tity, are several species of Poa and Glyceria. Several varieties 

 of Agropyrum repens, or couch-grass, occur abundantly in saline 

 soils, and also Agropyrum glaucnm, which is widely known as 

 "blue-stem," and is considered among the most nutritious of 

 grasses. Brizopyrum spicatum, now called Distichlis maritima, 

 and some species of Sporobolus, also form extensive patches or 

 meadows in saline soils. Besides, there is a large number of 

 grasses of low growth and of more spreading habit, which are 

 known in the Southwest and east of the Rocky Mountains under 

 the names of "mesquite" and "buffalo" grasses. The former 

 belong mostly to the genus Bouteloua, the most important species 

 being B. racemosa, or tall mesquite, and B. oligostachya, or low 

 mesquite. The true buffalo-grass is, botanically, Buchloe dacty- 

 loides, which in many places forms extensive fields over large 

 areas. It is of a low and densely tufted or matted habit. An- 

 other similar grass, but of little value, spreading out in low, wide 

 patches, is Munroa squarrosa. The above-mentioned species 

 form the larger proportion of the grassy vegetation of the great 

 plains. 



GRASSES FOR GENERAL CULTURE. 



The grasses form one of the largest and most widely diffused 

 families of plants, being spread over all habitable parts of the 

 globe. Some kinds are restricted to particular localities, others 

 are diffused over large countries, and a few are either native to 

 all the continents or have followed in the tracks of commerce 

 and discovery, so as now to be found in every principal country. 

 Over 3000 species are now known and described. Among these 

 there is an immense diversity in size and form of growth, some 

 kinds never growing more than an inch or two high, and others 

 in tropical regions attaining a height of 60 or 70 feet, with such 

 a density of stem as to be useful in the building of houses, for 



