RANGE PRESERVATION" AND EROSION CONTROL. 3 
the efficiency of the watershed in maintaining a permanent flow of 
irrigation water is greatly decreased. 
The importance of preserving the upper few inches of soil on the 
high ranges, and with it the vegetative cover, in order to regulate 
the stream flow, to maintain indefinitely the forage crop for grazing, 
and incidentally to prevent destructive erosion, is not always fully 
appreciated by the stockman and farmer. This is more especially 
true in localities where there is not an ample supply of irrigation 
water. 
In the belief that more water would find its way into the irrigation 
canals if the vegetative cover were appreciably thinned out, there 
has been a tendency in some localities toward destructive grazing. 
For instance, several sheep owners have expressed a desire to be per- 
mitted to graze Ephraim Canyon so closely as to pack the soil 
firmly and to decrease appreciably the present density of that vege- 
tation. They believed that a large amount of the water that is 
returned to the air in the form of evaporation from the vegetation, 
as well as that held by the rich surface soil, would, by thinning out 
the ground cover, be made available for irrigation. While it is true 
that if a given canyon were grazed destructively more water would 
undoubtedly rush down the water channels, and as a result a greater 
acreage of farm land could possibly be irrigated in early spring, 
there would be less water for subsequent irrigation at a time when 
the crops were seriously in need of it. With the destruction of the 
vegetative cover not even the lands most advantageously situated 
would have the benefit of a continuous stream flow for subsequent 
waterings during the season when even a light irrigation might 
result in the production of at least an average crop. In addition an 
enormous acreage of choice farm land would be destroyed by sedi- 
mentation, to say nothing of the high cost of upkeep of the irriga- 
tion ditches themselves. 
Most farmers and live-stock growers adjoining the National For- 
ests who are dependent upon the watersheds within the Forests for 
their irrigation water are likewise dependent upon the cool summer 
ranges for the maintenance of their stock. To graze any portion of 
the range destructively defeats the necessary economic balance 
between the range and live stock, on the one hand, and the farm land 
and farm crops, on the other. Much of the agricultural land ad- 
joining the National Forests is so remote from railroads as to make 
the live-stock industry a necessity in the economic harvesting and 
marketing of the farm crops. And aside from the loss of various 
public and private improvements as a result of torrential floods and 
sediment deposits, there would remain only a small amount of forage, 
mostly inferior, on the watershed after three or four seasons of 
