ALKALI SOILS. 



435 



lation near the surface is much less, even under irrigation. In 

 the natural condition the salts are in such cases often found 

 quite evenly distributed through soil columns of four feet, and 

 even more. This is an additional cause of the lesser injurious- 



.02 .04 06 .08 .10 12 .14- .16 .18 .20 .22 



\ 



N 



L_L 



FIG. 66. Distribution of Alkali Salts in Sandy Lands. 



ness of " white alkali." An illustration of the distribution of 

 the salts in very sandy lands, from the Tulare substation, is 

 given in Fig. 66. Here we see that the maximum is not at, 

 but some distance below the surface, the entire saline mass is 



