108 SOIL PHYSICS AND MANAGEMENT 



dissected upland terraces and valley plains. They are j poorly 

 adapted to general fanning. 



Everett Series. These soils range from light brown to light 

 reddish brown in color and are of silky texture and porous structure. 

 Large amounts of organic matter often occur in the immediate sur- 

 face. The subsoils are light brown to gray and usually gravelly and 

 porous. The material is of glacial origin and is derived from 

 basaltic and intrusive rocks. Heavy forests abound. Some of the 

 less porous types are adapted to dairying, orchard, and small fruits. 



Fresno Series. The soils vary in color from gray to light ash 

 brown, the heavier low-lying members sometimes assuming a dark 

 gray color as a result of accumulations of organic matter. They 

 are usually free from gravel ; a layer of white or bluish gray, im- 

 pervious, calcareous, alkali-carbonate hardpan varying in thickness 

 from a fraction of an inch to several inches separates the soil and 

 subsoil. The hardpan slowly softens under irrigation, but is nor- 

 mally impenetrable to the roots of growing plants. They occur as 

 old alluvial or colluvial deposits derived from granite rocks. If 

 the hardpan is not too near the surface and irrigation is practiced 

 alfalfa, grapes, fruits, and vegetables do well. 



Hanford Series. The soils are generally of light grayish 

 brown or buff to light brown color, the heavier members carrying 

 considerable organic matter and becoming dark gray to nearly black 

 when wet. They are micaceous, smooth to the touch, friable, and 

 of porous structure, generally free from gravel or boulders. The 

 soil material represents recent alluvial stream deposits derived 

 mainly from granite rocks. When irrigated they are well adapted to 

 tree fruits, raisin and table grapes, nuts, vegetables and truck crops. 



Hesson Series. The soils are dark reddish brown and under- 

 lain by yellowish brown to reddish brown subsoils of compact struc- 

 ture. Rounded gravel and small boulders are common on the sur- 

 face. The series occupies eroded terraces of undulating to rolling 

 topography, usually several hundred feet above the valley bottoms. 

 The material has been derived mainly from basaltic rocks and con- 

 sists of old alluvial or marine terrace deposits. They are well 

 adapted to general farming and orchard fruits. 



Melbourne Series. These soils are light brown to reddish 

 b'rown in color and often dark brown in the immediate surface. 

 When wet they are sticky and untractable, but under favorable 

 moisture conditions are easily tilled. They are derived princi- 

 pally from shales and sandstones. The topography varies from 



