Bui. 53, Bureau of Plant Industry, U. S. Dept. of Agricultur 



PLATE III. 



EXPLANATION. 



Suits survewd b\- Burc/iu <>! 



H CO.M.V. Contour In trnn I H) Hrrr . 



MAP SHOWING DISTRIBUTION OF SOIL TYPES AND OF ALKALI 

 INTHE IMPERIAL AREA, IN!HE SALTON BASIN, CAL. 



