60 



Plateaus are sedimentary. Thus we have different series of 

 soils in different parts of the mountains and plateaus. The 

 igneous and metamorphic rocks give rise to soils of the Porters 

 series j while the Dekalb series is formed from the weathering 

 of sandstones and sholes of sedimentary origin. 



Porters Series . - The Porters series includes the resid- 

 ual soils of the Appalachian mountains derived from igneous 

 and metamorphic rocks. These soils are quite similar to 

 those of the Cecil series, but are classed separately on ac- 

 count of the difference in topographic position. Some mem- 

 bers of the Porters series are eminently adapted to fruit 

 culture. 



Porters sand is a mountain soil. It consists of a 

 gray or yellowish sand averaging 8 inches in depth, underlain 

 by a coarse yellowish sand that runs into the disintegrated 

 rock at depths usually less than 36 inches. Rock fragments 

 are present in both the soil and subsoil and huge bowlders 

 are scattered upon the surface. This soil is derived through 

 the weathering of granite, gneiss and similar rocks. This 

 soil is of rather general occurrence in the mountains. 



Area of Porters sand Proport- 



ate extent 

 Acres per cent 



Albemarle Area, Harrisonburg Sheet 12,800 



«• w Waynesboro " 25,472 12.6 



" " Buckingham n 76,864 



