16 BULLETIN 159, TJ. S. DEPARTMENT OP AGRICULTURE. 



silt loam are also known to exist upon the low flat-topped divide 

 between the Potomac River and the Rappahannock River, at least 

 as far inland as the western boundary of Westmoreland County, Va. 

 Farther to the south, in tidewater Virginia, other soil series occupy 

 both the terraces and the interstream divides. These have been 

 classed as the soils of the Wickham and Norfolk series. 



A small area of the Sassafras sandy loam has been mapped on 

 the low terrace formed by the Talbot formation between Nor- 

 folk, Va., and the Atlantic coast. 



It will be seen that the various soils classed in the Sassafras series 

 may, almost without exception, be referred to formations of Pleis- 

 tocene age in the northern portion of the Atlantic Coastal Plain. In 

 the extreme northern portion of this section the relation of these soils 

 to glaciation is direct. Farther to the south and west this relation- 

 ship is chiefly shown by the presence of limited amounts of ice-borne 

 material mixed with the materials brought in from the Appalachian 

 and Piedmont regions and with material derived from the older for- 

 mations of the Coastal Plain. These have been deposited as a series 

 of marine, estuarine, and fluvial terraces which constitute the low- 

 lying section between the coast line and the more elevated land to the 

 interior. 



While the soils of the Sassafras series do not occupy the en- 

 tire extent of these geological formations they are quite generally 

 found along the interior margin where the glacial material and the 

 fine earth from Piedmont and Appalachian sources were mingled 

 with sediments derived from the older Coastal Plain deposits. 



All these classes of soil-forming material were sorted and rear- 

 ranged during the processes of transportation and deposited so that 

 the coarser materials are most frequently found at the base while the 

 surface materials may range from heavy silt loam to medium sand. 



Only the well-drained portions of the different terraces are occu- 

 pied by soils of the Sassafras series. Less well-drained areas give 

 rise to soils classed in the Portsmouth or Elkton series. 



The area of material referable to the soils of the Sassafras series 

 is usually greatest in positions around the mouths of streams which 

 issued from the glaciated areas to the north or whose headwaters 

 were affected by glaciation. As the terraces are followed to the west 

 and south other soil materials become predominant, and the higher 

 terraces are occupied by soils of the Norfolk, Leonardtown, and 

 Wickham series. 



SASSAFRAS SAND. 



Considerable areas of the Sassafras sand have been mapped in the 

 soil surveys of western Long Island, the Delaware River section of 

 New Jersey, in the Maryland-Delaware peninsula, and in the south- 

 ern Maryland counties lying between the Chesapeake Bay and the 



