6 THE AGRICULTURAL GRASSES OF THE UNITED STATES. 



wide reputation for their rich nutritious properties, for their ability to 

 withstand the dry seasons, and for the quality of self-drying or curing, 

 so as to be available for pasturage in the winter. This quality is due 

 probably to the nature of the grasses themselves and to the effect oi 

 the arid climate. It is well known that in moist countries, at lower 

 altitudes, the grasses have much succulence ; they grow rapidly, and their 

 tissues are soft ; a severe frost checks or kills their growth, and chemical 

 changes immediately occur which result in rapid decay; whereas in the 

 arid climate of the plains the grasses have much less succulence, the 

 foliage being more rigid and dry, and therefore when their growth is 

 arrested by frost the tissues are not engorged with water, the desiccat- 

 ing influence of the climate prevents decay, and the grass is kept on the 

 ground in good condition for winter forage. General Benjamin Alvord, 

 of the United States Army, has recently published an article on the 

 subject of these winter-cured grasses, and states that they only acquire 

 this property on land which is 3,000 feet above the level of the sea. 

 The region having such an altitude includes, he says, all, nearly up to 

 the timber line, of Montana, Idaho, Wyoming, Utah, Nevada, Colorado, 

 and I^ew Mexico ; five-sixths of Arizona, one-half of Dakota, one-fourth 

 of Texas, one-fifth of Kansas, and one-sixth each of California, Oregon, 

 and Washington Territory, embracing about one-fourth of the area of 

 the whole United States. 



Many of the grasses of this extensive region are popularly known as 

 bunch grass," from their habit of growth ; others are known as ''mes- 

 quite" and '^gramma grass." These consist of many species of differ- 

 ent genera, some 6f them more or less local and sparingly distributed^ 

 others having a wide range from Mexico to British America. 



The most important of the " bunch grasses " may be briefly mentioned 

 as follows : Of the genus 8ti2)a there are several species ; Sti2m comata 

 and lSU])a setigera occur abundantly in New Mexico, Texas, Arizona, 

 and California, reaching to Oregon. In Colorado, Kansas, and all the 

 prairie region northward, stretching into British America, Stipa juncea 

 is the principal one of the genus. On the higher plateaus and near the 

 mountains the Sti])a viridula is very common, extending from Arizona 

 to Oregon and British America. Somewhat related botanically is 

 Eriocoma cuspidata, a very rigid bunch grass, with a fine, handsome 

 panicle of flowers. It is equally widespread with the preceding. An- 

 other widely diffused grass is Aira ccespitosa, varying much in size and 

 thriftiness according to the altitude and amount of moisture where it 

 grows, but always having a light, elegant spreading panicle of silvery- 

 gray flowers. 



One of the most extensively diffused grasses is Kceleria cristatciy 

 varying in height from to 1 foot to 2^ feet, with a narrow and closely- 

 flowered spike. Several species of fescue grass {Festuca) are inter- 

 mixed with the vegetation in varying proportions j the most impor- 

 tant of these, probably, are Festuca ovina in several varieties, and 



