4 SOILS OF THE EASTERN UNITED STATES. 



Clarksville clay loam lacks this surface covering of silt to a large 

 degree, while the Clarksville stony loam is marked by accumulations 

 of stone and chert to such an extent that they form a considerable 

 proportion of both the surface soil and subsoil, not infrequently 

 interfering with cultivation. 



The Clarksville silt loam and its associated soils differ from the 

 soils of the Hagerstown series from the fact that they are derived 

 from siliceous and cherty limestones and not from the massive blue 

 and rather pure limestones to which the latter series owes its origin. 

 Moreover in areas where both series occur, the Hagerstown series 

 is uniformly found at the lower levels, occupying valley positions, 

 while the Clarksville series occupies the plateaus and rims around 

 the basins and valleys where the Hagerstown soils are found. The 

 surface soil of the Clarksville silty loam is prevailingly gray or pale 

 yellow in color, while the surface soils of the Hagerstown series are 

 usually brown or deep yellow shading into brown. 



SURFACE FEATURES AND DRAINAGE. 



The Clarksville silt loam is preeminently an upland or plateau 

 soil and its surface varies from minor areas almost absolutely level 

 to extensive tracts, comprising the main body of the type, which are 

 gently rolling and undulating. Around its margins the Clarksville 

 silt loam also occupies rounded hills of gentle slope, where erosion 

 has not been sufficiently active to destroy the characteristics of the 

 type. In very few instances can the surface configuration of areas of 

 the type be said to be more than sloping. 



In western Kentucky and western Tennessee the altitudes attained 

 by the Clarksville silt loam range from about 450 feet to 700 or 800 

 feet above tide level. Eastward from this region the surface rises 

 gently until altitudes of 1,000 or even of 1,200 feet are attained, 

 where the Highland Rim of eastern Tennessee slopes gradually up to 

 the Cumberland Plateau. West of the Mississippi River, in the Ozark 

 borders, the altitude of the areas occupied by the Clark?ville silt 

 loam similarly increases gradually from about 500 feet in the north- 

 ern and northeastern region to approximately 1,000 feet where 

 the Ozark border abuts Against the more central portions of the 

 uplift. In both of these general localities the Clarksville silt loam is 

 found upon the more level tracts at the higher elevations, but not 

 attaining to the highest hills and slopes which are usually occupied 

 by the Clarksville stony loam or some other type of soil. In northern 

 Arkansas the Clarksville silt loam is found upon distinct benches and 

 fragmentary plateau areas at altitudes ranging up to 1,200 or even 

 1,500 feet above sea level. 



In spite of its elevated position and of the fact that deep drainage 

 channels have been cut through the elevated plateau regions occu- 



