ORIGIN OF SOILS 



75 



into thirteen provinces, based chiefly on climate, origin and topo- 

 graphy of the soils. These are better shown in the map than 

 described. Two great divisions are based on climate ; first, humid, 

 and second, arid and semi-arid. The soil provinces are as follows : 

 Humid Division. i. Atlantic and Gulf Coastal Plains. These 

 consist of a belt of land narrow in New Jersey but much wider 

 towards the south. The surface is a plain cut into hills and 

 valleys by rivers, about 200 to 300 feet above sea level along the 

 inner margin, but nearer the coast it has many areas with deficient 

 drainage. The soils are made up of gravels, sands, and sandy 

 clays. The deposits on the Atlantic coast are derived from the 

 Piedmont Plateau through oceanic agencies, while the deposits on 

 the gulf coast are derived from material transported from glacial 

 deposits and from the western plains. There are also some soils 

 derived from limestone deposits. 



Fig. 23. Shell rock, Florida. 



2. Piedmont Plateau. This area lies between the coastal plain 

 and the Appalachian Mountains, and is most extensive in Virginia, 

 North Carolina, South Carolina, and Georgia. The altitude 

 varies from 300 to over 1,000 feet above sea level. These soils 

 are derived largely from the weathering of igneous and 

 metamorphic rocks in place. The prevailing series of these soils 

 are the Cecil series and the Chester series. Both these series 

 usually contain mica and quartz. 



