102 SOIL PHYSICS AND MANAGEMENT 



light gray to white, calcareous, floury, silty clay subsoils. They are 

 derived from calcareous conglomerate. The more loamy types are 

 good for general farming. 



Summit Series. The soils are dark gray to black, with mot- 

 tled yellow and gray subsoils. They occupy nearly flat to sharply 

 rolling prairie? and are derived from calcareous shales. Corn, 

 wheat, oats, timothy, clover, and alfalfa are the principal products. 



Vernon Series. The soils are reddish brown to red. The 

 subsoils are usually red but sometimes reddish brown or brown in 

 the upper part. Corn, wheat, oats, cotton, kafir and sorghum are 

 the chief products. They are derived from sandstones and shales. 



(2) Glacial Material. The soils derived from this material 

 do not occur extensively in this region. They are represented 

 by a single series, the O'Neill. The soils are dark gray to 

 brown, underlain by light brown subsoils resting upon sand or 

 gravel. The topography varies from nearly level to rough and 

 broken. The series is derived from glacial drift which underlies the 

 loess. The deeper members have a high value for small grains, corn, 

 potatoes, and forage crops. 



(3) Lake-laid Material. The soils of lacustrine origin are 

 of only local occurrence. They are represented by three series of 

 small extent. 



(4) Wind-laid Material. This series occupies a very exten- 

 sive area in Kansas, Nebraska and South Dakota. The principal 

 series are the Canyon, Colby, and Valentine. 



Canyon Series. These soils are light brown Or ashy brown 

 and the subsoils are yellowish gray. They are mainly derived from 

 loessial material and are adapted to grazing and locally to corn, 

 milo, kafir, and sorghum. The series occurs in Kansas and 

 Nebraska. 



Colby Series. The soils are ashy gray or brownish gray. The 

 upper subsoil is similar to or lighter in color. They are derived 

 from loessial deposits. Wheat, corn, and forage crops are grown. 



Valentine Series. The soils consist of brown to dark brown, 

 with light brown to brown and usually heavy subsoils. They are 

 adapted to corn, potatoes, truck, and hay crops. 



(5) Alluvial Fan and Valley Filling Material. These have 

 been derived from the great areas of Tertiary deposits with those 

 less extensive areas of local alluvial fan and colluvial material. 



