CLASSIFICATION BY THE BUREAU OF SOILS 97 



VII. RIVER FLOOD PLAINS PROVINCE 



The soils of this province occupy the first bottoms and adjoin- 

 ing terraces of streams throughout that section lying east of the 

 Great Plains region. Some areas of flood plains soil cover the bot- 

 toms and terraces of valleys which have been abandoned by their 

 main streams. 



These soils occur in continuous and interrupted strips along 

 the banks of streams. They vary from narrow strips a few rods 

 wide along the minor drainage courses and those streams which 

 pass through gorge-like valleys to broad bottoms several miles in 

 width. The broadest strip of strictly alluvial land is along the 

 Mississippi Kiver, where, at its confluence with the Arkansas, it is 

 75 to 100 miles. 



The soils of this province include two topographic divisions: 

 (1) The first bottoms or present flood plains, and (2) the terraces 

 or old flood plains. The material composing these soils is derived 

 fiom very widely distributed sources and from every species of 

 rock. The principal series are as follows: 



Bibb Series. This series is marked by light-colored to white 

 compact surface soils and by compact plastic and white or mottled 

 white and yellowish subsoils. The material is derived mainly from 

 Coastal Plains soils. They are best suited to grass and pastures 

 under present conditions. 



Blanco Series. These have gray to light brown soils and 

 brownish subsoils which in the lower portions change to plastic 

 heavy materials of a decidedly brown color. The soil and subsoil 

 are calcareous. These soils occupy terraces mainly above overflow. 

 Soils are well adapted to cotton, corn, Irish potatoes, and alfalfa. 



Cahaba Series. The .surface soils are brown to reddish brown 

 and the subsoils are yellowish red to reddish brown. They are ter- 

 races principally above overflow. These soils are well suited to cot- 

 ton, corn, oats, and forage crops. 



Cameron Series. These are soils of dark brown to black color 

 and tenacious character and highly calcareous subsoil. The series 

 occupies broad, shallow basins, occurring typically between river 

 channels, and in general is ]x>orly drained. The lower ]x>rtions re- 

 main flooded during the greater part of the year. Alkali is fre- 

 quently present, in the lower depression. fJood crops of corn, sugar 

 cane, cotton, and vegetables are successfully grown. 



Congaree Series. The soils and subsoils of this series are 

 brown to reddish brown, there being comparatively little change in 

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