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JOHN ERNST WEAVER 



cated. On July 6 no water was available in the second foot of 

 soil and only a small margin over the wilting coefficient was 

 present at 3 feet. The broken line indicates that on December 

 13 of the preceding winter the soil was drier at 3, 4 and 5 feet 

 respectively, than at any other time indicated. The fall rains 

 had not then penetrated beyond 2 feet. While excavating 

 root-systems during the fall, winter, and spring, an excellent 



Fig. 3. Graphs showing the march of soil water to a depth of 5 feet on a 

 northeast slope from April 18 to August 15, 1914, and the water content of the soil 

 on December 6, 1913. 



opportunity was offered to study the rates of penetration. The 

 water penetrated very slowly and at about equal rates on all 

 slopes. By October 18 only the surface layer of 8 inches was 

 wetted, and in late March the wet soil reached a depth of not 

 more than 4 feet. The dotted graphs in the figure indicate the 

 soil moisture on the northeast slope. Aside from the lower 



