4 BULLETIN 675, L T . S. DEPARTMENT OF AGEICULTUBE. 
excessively heavy grazing. The farmer-stockman can not afford 
to do without this feed. The temporarily larger profits that might 
be derived from overgrazing would soon be offset by the somewhat 
more moderate but continued profits accrued from a stable stock 
industry in which the lands are grazed on the basis of a sustained 
yield. 
If instead of grazing merely one canyon beyond its carrying 
capacity the entire forest unit, and, indeed, all forest land of irregu- 
lar topography throughout the West were likewise grazed, untold 
injury to farm land and other property from destructive erosion and 
floods would result, a sustained stream flow would no longer exist 
on the watersheds, and there would be neither a normal supply of 
water for the irrigation of the adjoining farm lands nor of forage for 
the live stock on the extensive forest ranges. Without these produc- 
tive elevated range lands upon which to summer the stock, homes on 
many farms could no longer be maintained; and it would not be 
long before the lands would revert to the original wild state. 
Within the boundaries of the Manti National Forest of Utah there 
is a belt of approximately 47,000 acres of land along the east side 
of the divide which is badly depleted as a result- of overgrazing and 
erosion, making necessary a regulation protecting* the areas from 
grazing part of the year. Along the west side of the divide there is 
a similar belt of about the same acreage where erosion is also causing 
damage. These belts are practically timberless, and are of value 
chiefly as .watersheds, from which stream flow for irrigation is sup- 
plied, and for the grazing resources which they afford. That these 
and similar eroded lands would originally support a cow or the 
equivalent in sheep on from one-third to one-fifth the acreage re- 
quired at the present time is evidence of the enormous loss annually 
to the live-stock industry alone. The soil and plant foods on these 
already relatively unproductive lands continue to be carried away 
by the run-off following each storm ; and the destruction, where well 
advanced, is sure to continue until preventive measures are fully 
established. 
Typical instances of the damage caused by erratic run-off and 
erosion are well worth citing. On July 28, 1912, a rainstorm oc- 
curred at the head of Ephraim Canyon, on the Manti National 
Forest, within a belt of 2 miles and between elevations of 9,000 and 
10,500 feet. There was no rain in the valley or on the mountain 
below, approximately, 8,000 feet. The storm of 0.41 of an inch of 
rain fell intermittently, but at no time with special violence, for a 
period of two hours. A flood of sufficient force developed to reach 
to the city of Ephraim, 10 miles below, covering the streets and some 
farm land, and filling the basements of buildings with mud and 
debris. Laden with silt, logs, vegetable matter, and. during the 
