Yakima Series. 139 



San Joaquin red adobe. — Sticky red adobe, with texture of loam, 

 6 feet in depth; iisuaUy a layer of red sandstone hardi:)an in lower 

 3 feet. Margins of plains adjacent to foothill streams; derived 

 from foothill stream wash, .\dapted to grain crops. 



1 



Soil (3) 18 



Subsoil (1) 15 



Acres. 

 Fresno, Cal 12, 691 



San Joaquin black adobe. — Heavy black or brown adobe soil, 4 

 to 6 feet deep. Subsoil varies from sandy adobe to heavy clay 

 adobe, or it may be decomposing shale. ^Margins of valleys along 

 foothill streams in California, often extending out into the val- 

 leys. Derived from crystalline rocks or shale. Soil is difficult to 

 till, but very productive. Adapted to grain crops and used at 

 present for citrus fruits where water supply is adequate. 



1 



Soil (18) 5 



Subsoil (17) 2 



Acres. 



Fresno, Cal 5, 664 



Hanford, Cal 5, 470 



Los Angeles, Cal 37, 440 



Lower Arkansas Valley, Colo . . 4, 096 

 Lower Salinas Valley, Cal 11, 580 



Acres. 



San Gabriel, Cal 23, 650 



San Jose, Cal 30, 400 



Santa Ana, Cal 16, 038 



Ventura, Cal 4, 290 



YAKIMA SERUMS. 



This series is derived mainly from the disintegration of basaltic 

 rocks and volcanic ash material. 



Yakima stony loam. — Basaltic bowlders and outcroppings in too 

 great quantity to permit of cultivation. Space between bowlders 

 occupied by small patches of Yakima sandy loam. Occurs on hill- 

 sides and plateaus in valleys. Well drained and free from alkali. 



Acres. 

 Yakima, Wash 8, 960 



Yakima gravelly loam. — A loam soil containing from 25 to 80 per 

 cent of rounded, waterworn basaltic gravel, usually from one-half 

 inch to 3 inches in diameter. Occupies valleys along small 



