24 FORAGE CONDITIONS ON NORTHERN BORDER OF GREAT BASIN. 



wheeleri) and bunch wheat grass (Agrojjyron spicatum). Beyond the 

 blue-grass zone of the foothills and lower mountain areas occur the 

 finest pasture lands of the region. These, while in all probability 

 furnishing no more nutritious grass than the foothills, are much more 

 attractive and in some respects much more important than the former, 

 owing to the fact that they are more often free from shrubbery and 

 other plants with little or no forage value, and consequently furnish 

 a larger quantity of feed per acre. This is the sheep fescue area, 

 and this important grass in one of its two principal varieties grows 

 often to the exclusion of all other forms of vegetation. 



The first of these zones, that including and immediately surround- 

 ing the barren basin bottoms, is greatly modified in certain localities. 

 Wherever there is a small valley contributing water to the basin or 

 river bottom, the general alkalinit}^ of the region has been neutralized 

 by the beneficial action of the rich sediment brought down from the 

 mountains, or otherwise counteracted to such an extent that the soil 

 has been made very rich and productive. By these methods delta-like 

 areas have been built up in the lower valleys or ravines or in borders 

 of greater or less width along the river courses. It is in these areas 

 that the ranches of the region are built, and it is upon them that the 

 region is dependent for its winter feed, consisting sometimes of excel- 

 lent but often very ordinary crops of native hay and forage plants. 

 On the more elevated portions of the lower valleys where the drainage 

 is good and where, under natural conditions, the black sage (Artemisia 

 tridentata) predominates, is located the best soil, as experience has 

 demonstrated, for the culture of alfalfa, the main cultivated hay crop, 

 and, indeed, about the only crop of any kind upon which much depend- 

 ence is placed. 



One may therefore recognize three t}^pical forage zones or areas, 

 namely: Lowlands, including river bottoms, and low areas in basin- 

 shaped depressions furnishing winter feed in the shape of pasture and 

 hay, but more especially the latter at the present time; the mesa, 

 including the intermediate zone between the lowlands and the next 

 named, furnishing but little feed except browse, its main resources 

 consisting of shrubby plants, such as true sages, salt sages, white sage, 

 and red sage; and the highlands, including the foothills and mountain 

 region, which furnishes practically the entire summer pasture. The 

 general appearance of some of the lowland areas, with their character- 

 istic vegetation, are shown in Pis. II, fig. 2; XIII, fig. 2; XIV, fig. 2, 

 and XV, figs. 1 and 2. The surface soil on the mesa region is for the 

 most part uncovered, the shrubby vegetation usually being much scat- 

 tered and only from 2 to 3 feet high. Some idea of this region can be 

 gained from Pis. I, fig. 2, and III, figs. 1 and 2. It may be a broad, 

 gentle, sloping plain, as shown in the first figure, or exceedingly broken 

 and fissured hj deep ravines. The highland, including, as stated above, 

 both foothills and mountains, while producing a much larger amount 



