100 SOIL PHYSICS AND MANAGEMENT 



and high in organic matter. The subsoils are lighter drab or gray. 

 They occur as first bottoms along the Mississippi. They grow 

 large crops of grass and corn. One million nine hundred acres have 

 been mapped. 



Waverly Series. The soils are light gray in color and overlie 

 gray or mottled yellowish and grayish subsoils. They occur as first 

 bottom land along streams issuing from the loessial region of the cen- 

 tral prairie states. They are fairly well adapted to corn and grass. 



Wheeling Series. These soils are brown to yellowish brown 

 and are underlain by gravel usually within 3 feet of the surface. 

 They occupy the gravel terraces along the streams that flowed from 

 the ice-covered regions. 



Yazoo Series. The color of the surface soil ranges from gray 

 slightly darkened with organic matter to light brown, while the 

 subsoils are of mottled grayish, rusty brown and sometimes bluish. 

 They, occur in the flood plains of the Mississippi river. They are 

 well suited to cabbage, onions, peas, lettuce, Irish and sweet po- 

 tatoes, cucumbers, melons, etc. Cotton, corn, and forage crops give 

 good results on the heavy types. 



VIII. GREAT PLAINS REGION 



The Great Plains Region is bounded on the north and east by 

 the Glacial and Loessial province, on the east and southeast by the 

 Limestone Valley and Uplands province and the Gulf Coastal 

 Plains, and on the west by the Rocky Mountains. It has a maximum 

 width of 600 miles. In altitude it varies from 1000 to 6000 feet 

 above sea level. Where not eroded it is a level or gently sloping 

 plain. There are areas of excessively eroded or " bad land " to- 

 pography. The Great Plains region extends from the Rio Grande to 

 Canada. The Upland soils are divided into the following as to 

 origin : 



(1) Residual Material. The residual soils are of widespread 

 occurrence and constitute the most extensively developed and im- 

 portant province. Owing to their wide distribution these soils are 

 subject to a wide variation of climatic influences that have been 

 important factors in their formation. The series are as follows : 



Bates Series. These are of dark gray color, while the subsoils 

 are yellowish and mottled red or yellowish or buff in the upper part 

 and mottled with yellow and red in the deeper sections. They are 

 treeless and of undulating topography. The crops are chiefly corn, 

 wheat, flax, and oats. 



