4 SOILS OF THE EASTERN UNITED STATES. 



It frequently occupies the crests of ridges on the upland or adja- 

 cent to stream channels. Where the ridges are broad the surface of 

 the type is undulating to rolling, but upon narrower ridges, and in 

 all cases along the margins of the more elevated portions, the slopes 

 to adjacent territory are liable to be steep and usually gullied. The 

 depth of the surface fine sandy soil is usually greatest upon the crests 

 of the ridges, while the sandy clay subsoil is encountered at shallower 

 depths along the more gentle slopes. Outcrops of the subsoil where 

 erosion has cut away the surface materials along the margins are 

 frequent. 



In the eastern Gulf region the Orangeburg fine sand lies at alti- 

 tudes ranging from 100 to 250 feet above tide level. In the western 

 Gulf region it is usually found at altitudes between 150 feet and 500 

 feet, where it is usually more rolling and frequently occurs in large 

 areas upon the elevated uplands. 



Owing to the sandy texture of the soil, to its elevated position, and 

 to its rolling surface features, the Orangeburg fine sand is well 

 drained, with a tendency toward excessive drainage upon the crests 

 of ridges, especially where the surface soil has a depth greater than 

 2 feet. Upon the more gentle slopes the soil is less droughty and 

 better suited to the production of general farm crops. Only a few 

 level areas, somewhat depressed below the general elevation of the, 

 greater portion of the type, are poorly drained. 



The same factors which furnish excellent drainage also favor the 

 excessive erosion of the type. Although the soft, permeable surface 

 soil readily absorbs a large proportion of the moisture which falls 

 upon it, yet its incoherence and its elevated position favor rapid 

 erosion. The steeper borders of the type are badly eroded, where 

 deep gullies are being cut back from the major stream channels into 

 th<? more elevated uplands and where the steep gradient favors the 

 rapid removal of the fine-grained incoherent material of the Orange- 

 burg fine sand. Upon the more gently rolling or undulating areas 

 of the type, erosion is scarcely perceptible, although there is a tend- 

 ency toward the constant removal of fine sand from higher altitudes 

 to lower and more level areas. In general the Orangeburg fine sand 

 is either too steeply sloping to justify cultivation, or the more level 

 cultivable areas are little susceptible to destructive washing. 



LIMITATIONS IN USE. 



The principal limitation in the use of the Orangeburg fine sane 

 arises from the sandy texture and considerable depth of the surfs 

 soil. While a considerable proportion of the total rainfall penetrat 

 the surface soil and is readily absorbed, yet the depth to the clay sul 

 soil permits of rapid downward percolation, causing the surface 

 dry rapidly even after heavy rains. As a result the type must 



