REVIEWS 



Range Preservation and its Relation to Erosion Control on Western 

 Grazing Lands. By A. W. Sampson and L. H. Weyl. U. S. Dept. of 

 Agriculture, Bulletin No. 675, June 25, 1918, 35 pp. 



With the rapidly increasing demand for available forage the western 

 stock interests are keenly alive to the importance of investigations that 

 have for their object the improvement of the carrying power of much 

 of our western range. Sampson and Weyl have recently published the 

 results of a comprehensive study on the relation between range preser- 

 vation and erosion and its control on grazing lands in the West. The 

 bulletin has 35 pages of printed matter, well illustrated by photographs, 

 diagrams, and line drawings. The data were obtained, for the most 

 part, on the high summer range of the Manti National Forest, in central 

 Utah, where conditions influencing erosion are similar to those prevail- 

 ing in most mountainous areas between the Rocky Mountains and the 

 Sierras of California. The study as originally planned will require a 

 number of years, but the data already available are considered so im- 

 portant they are published prior to the completion of the study. After 

 outlying the purpose of the study, emphasis is placed upon the damage 

 caused by erosion. On the areas studied the greatest damage from 

 erosion was when overgrazing was practiced and the ground cover de- 

 stroyed or seriously impaired. Before these areas were overgrazed and 

 the ground cover impaired, erratic run-oflf and erosion were practically 

 unknown. It is pointed out that the damage is not confined to the de- 

 crease in the forage yield and the silting over of adjoining agricultural 

 land, but the efficiency of the watershed in maintaining a permanent 

 flow of irrigation water is greatly decreased. When the range has been 

 grazed destructively, the economic balance between range and live stock 

 on the one hand and farm land and farm crops on the other has been 

 greatly impaired. A number of typical examples are given of the dam- 

 age from erratic run-off and erosion following overgrazing. As one 

 example, a rain of 0.55 of an inch, the greater part of which occurred 

 within an hour, fell at the head of Becks Canyon on July 20, 1912. 

 Although the rain started at 11 a. m., at 11.45 ^- ^n- ^ flood was pouring 

 out of a side canyon from an area of less than 1,500 acres at an eleva- 

 tion of 10,000 feet. The soil, denuded of vegetation due to overgrazing, 

 was clay-loam. There was little outcrop of rock and the slopes were 

 moderately gentle. An examination showed that the soil had been 

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