CLASSIFICATION BY THE BUREAU OF SOILS 107 



flat topped mesas and many isolated, elongated mountain ridges. 



(a) Uplands. Glendale Series. These soils range from light 

 gray or grayish brown to dark brown or chocolate in color and are 

 underlain by gray to light brown highly calcareous subsoils. When 

 irrigated they produce alfalfa, forage crops, vegetables, grapes and 

 citrous fruits. 



Imperial Series. The soils are generally of light or reddish 

 color, the heavier members being compact and plastic, poorly 

 drained and alkaline. The soil material represents old lake deposits 

 derived mainly from sandstone and shales. 



Indio Series. The soils are light gray to slate colored, porous, 

 and underlain by coarser sand. They are derived from granites 

 mixed with shales and sandstones. Melons, sweet potatoes, truck 

 crops, etc., are grown under irrigation. 



Yuma Series. These soils are usually rather compact. The 

 subsoil is similar to the soil except that at a depth of 2 to 6 feet 

 layers occur that have the particles slightly cemented together with 

 calcium carbonate. They generally occupy mesh lands. They are 

 adapted to citrous fruits, figs, grapes, and vegetables. 



(b) River Flood Plains. Gila Series. The soils of the 

 lighter types are prevailingly of light yellowish brown, light grayish 

 brown or slightly reddish brown color and porous structure. The 

 heavier types range in color from brown or chocolate brown to dark 

 gray or black and are compact. The series occupies stream flood 

 plains and second bottoms or recent terraces. 



XIII. PACIFIC COAST REGION" 



This region includes the area of California, Oregon and Wash- 

 ington west of the Cascade, Sierra Nevada, Sierra Madre and San 

 Jacinto Mountains. A broad valley extends almost the entire 

 length with only slight interruptions. 



(a) Upland. Altamont Series. Soils are light brown to dark 

 brown in color with a reddish tinge when wet. Subsoil is heavy, 

 rather compact reddish brown or light brown clay loam or clay. 

 The series occupies hilly to mountainous regions. The members 

 of this series are residual, being derived from sandstone and shales. 

 Hay and fruits are grown. 



Corning Series. The soils are of reddish brown or red to deep 

 red color, rather shallow, easily puddled, and hard to handle except 

 under proper moisture conditions. The subsoils are reddish brown 

 to deep red. of heavy and compact structure and impervious to 

 moisture. The soils occupy sloping to undulating and hilly and 



