SOIL SURVEY OF THE RED BLUFF AREA, CALIFORNIA. 19 



terrace lying south of the modern channel of Redbnnk Creek. Nar- 

 ro^ver belts occur along all the other eastward-flowing streams. 



Northwest of Corning there is a considerable area of Tehama soils 

 derived directly from the weathering of the Red Bluff formation. 

 This area occurs in gently rolling country and merely represents an 

 area of Red Bluff material that has been eroded down to a very gently 

 undulating plain. It is residual in origin, while the other areas are 

 alluvial in origin. 



The Tehama types are prevailingly yellowish or yellowi^^h brown in 

 color, deeper than the soils of the previously mentioned series and 

 fairly friable. A heavy subsoil usually occurs. They are well 

 adapted to irrigation, but yield scant crops under dry farming. 

 The distribution of this series is very general over the west side. 



The Maywood series comprises five types of soil formed on the 

 terraces and alluvial fans of the small streams in the southwestern 

 part of the area. They occur on the level areas bordering these 

 streams, and lie below the level of the series already named. The 

 areas are usually broader to the west and narrow to the east on 

 account of the broadening of the alluvial fans upstream. The series 

 as a whole is grayish or yellowish gray in color and more friable 

 than the Tehama series. This series is better adapted to dry-farmed 

 fruit and grain than any of the series before mentioned, but yields 

 are light and could be greatly increased under irrigation. The May- 

 wood series occurs at intervals over the west side, being confined to 

 that section. 



In the southern part of the area occur inextensive bodies of soil 

 material derived by washing or erosion of adjacent more elevated 

 bodies of soils, viz, the Corning series. It is deposited over lower 

 valley plains, local fiats, or depressions. It represents eroded ma- 

 terial modified by local conditions of restricted drainage, of dark- 

 gray color, and compact, refractory structure. In this area the 

 material gives a single soil type. It is classed as a member of the 

 Kirkwood series. 



Several of the west side major streams have constructed alluvial 

 bottoms from foreign material along their courses in the Red Bluff 

 area. These soils are mostly derived fi'om rocks along the sources 

 of Thomas and Elder Creeks in the foothills and mountains of the 

 Coast Range, and have not been greatly influenced by addition of 

 material eroded from adjacent soils. These depressed valley soils 

 enter the west edge of the survey and continue to the great alluvial 

 plain of the Sacramento, where they gradually lose their identity. 

 They are dark in color, deep and friable in character, and excellent 

 soils for every purpose. Three types were found and classed as the 

 Elder series. 



