174 CONTROL OF EROSION ON RANGE AND PASTURE 



come under the observation of the author might be cited, but 

 one will suffice. The incident to be related occurred on the 

 Manti Forest in central Utah, on July 28, 191 2. The rainstorm 

 was confined to an overgrazed belt of about 2 miles between the 

 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 fall of .41 of an inch of rain continued intermittently for a 

 period of two hours, but at no time with great violence. A 

 flood of sufficient force developed to reach to the city of Ephraim, 

 10 miles below, covering the streets and some farm land, and 

 fining the basements of many buildings with mud and debris. 

 Laden with silt, logs, vegetable matter, and even with rocks, 

 some of which contained as much as 30 cubic feet of material, 

 the flood destroyed wagon roads, trails, and irrigation ditches 

 (Fig. 55)- 



The incalculable damage caused by the concentration of 

 waters in the Mississippi River at various times is famihar to 

 everyone. The magnitude of the damage that resulted from the 

 overflow and devastation of the fertile bottom lands baffles 

 comprehension. The losses on some of the river branches have 

 been computed, however, and they serve to show how serious is 

 the situation. 



From March 15, 1907, to March 20, 1908, barely more than 

 a year, three floods of the Ohio River caused a direct loss at 

 Pittsburg, Pennsylvania, of about $6,500,000. It is estimated 

 that the average annual damage caused by floods of the Ohio 

 River and its tributaries is not less than $50,000,000; yet it is 

 believed that there is not a stream emptying into the Ohio 

 River whose flow could not be regulated by reestablishing and 

 preserving the vegetative cover on the contributing water- 

 sheds. 



Innumerable instances of the appaUing damage caused by 

 erosion could be related; but the results when erosion is per- 

 mitted free play are, ultimately, the same everywhere — the 

 ruination of soil fertility and the destruction of practically all 

 property found in the path of the deluge. 



