110 LANDS OF THE ARID REGION OF THE UNITED STATES. 
that can be obtained during some seasons of deep snows. This shrub is a 
congener of the well known mountain mahogany, C-. ledifolius, which grows 
at higher altitudes, and has truly evergreen foliage. 
The small perennial plant Hwrotia lanata, or ‘ White sage”, found 
growing in the valleys and plains, is held in high esteem as winter food for 
stock. 
The growth of grass, even on the plateaus, is often scant; on the foot 
hills it becomes less, and farther away from the highlands it still dimin- 
ishes in quantity until absolute deserts are found. Most of the grasses 
seem to protect themselves from the great aridity by growing in bunches. 
They appear to produce proportionately a greater amount of seeds than the 
grasses of the Humid Region, and their nutritive qualities, especially in 
winter, seems to be due thereto. In general, the grasses seem to have large, 
strong stems, and are not so easily broken down as those of the Humid 
Region, and the rains and snows by which they would be so broken down 
are infrequent. Again, for these reasons, the grasses, standing long after 
they are cut by frosts, cure themselves, forming thereby a winter pasturage. 
The irrigable lands of Utah will be discussed more thoroughly and in 
detail in subsequent chapters by Mr. G. K. Gilbert, who has made the Great 
Salt Lake District his study; by Capt. C. E. Dutton, who has prepared the 
chapter on the irrigable lands of the Sevier Lake Drainage, and by Prof. 
A. H. Thompson, who has written the chapter on the irrigable lands of the 
Colorado Drainage. 
The following is a table of the irrigable lands, arranged by districts, 
as discussed in the present chapter. The table is compiled from those 
presented in subsequent chapters. 
