SOILS OF THE EASTERN UNITED STATES AND THEIR USE XXXVII. 



THE HAGERSTOWN CLAY. 



GEOGRAPHICAL DISTRIBUTION. 



The Hagerstown clay is an extensive limestone soil found within 

 the great valley of Virginia, the limestone valleys which are enfolded 

 into the Appalachian Mountain system, and in the bluegrass region 

 of Kentucky. It has been encountered in 12 different soil survey 

 areas located in seven different States, and mapped to a total extent 

 of 371,290 acres. It is probable that there are upw.ard of three and 

 one-half million acres of the type altogether. 



Throughout the Appalachian region the floors of the principal 

 valleys are occupied by limestone. A group of soils known as the 

 Hagerstown series is derived from these limestones. The chief soil 

 of the series, the Hagerstown loam, is very extensively developed. 

 Associated with it in nearly all of the different valleys will be found 

 smaller areas of the Hagerstown clay. Although farmed in the same 

 general way, the two soils differ materially in their characteristics. 

 It will be shown that these differences affect the agricultural occu- 

 pation of the type very materially. 



It is probable that additional extensive areas of the Hagerstown 

 clay will be found in northern Alabama, northwestern Georgia, 

 eastern Tennessee, and the bluegrass region of Kentucky. Large 

 areas are already known to exist through the great valley of Virginia 

 (the Shenandoah Valley), and in the Hagerstown Valley of Mary- 

 land. A large number of smaller valleys lying to the west of the 

 great valley also contain considerable areas of the Hagerstown clay. 

 It is thus a widely developed and extensive soil type of high value 

 for agricultural purposes. 



CHARACTERISTICS OF SOIL AND SUFSOIL. 



The soil of the Hagerstown clay is uniformly a dark reddish brown 

 or deep-red clay loam or clay, decidedly silty, but somewhat sticky 

 and plastic owing to the presence of a large amount of clay, particu- 

 larly over areas where the surface soil is shallow. The depth is 

 extremely variable in different areas ranging from 2 or 3 inches on 



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