GENERAL FEATURES OF THE SOILS. 



The entire area of Chatham County, Ga., falls within the seaward 

 section of the Atlantic and Gulf Coastal Plain. This extensive soil 

 province stretches from Long Island, N. Y., southward to the Florida 

 peninsula, and thence swings westward along the Gulf of Mexico to 

 the Rio Grande. It is a region of low relief and one much inter- 

 sected by sounds, estuaries, and the lower courses of numerous rivers 

 which have their headwaters in the Mountain and Piedmont regions 

 farther inland. Through the Coastal Plain section of the country a 

 majority of the navigable rivers flow from the inland regions to the 

 sea. It is, therefore, largely accessible by water to vessels of medium 

 and light draft. Chatham County is bordered by two such rivers, 

 the Savannah and Ogeechee. 



The materials comprising Chatham County, in common with other 

 Coastal Plain counties, are principally unconsolidated sands and 

 clays, with occasional minor deposits of gravel. This material has 

 been eroded from the surface of inland regions and transported sea- 

 ward by ancient streams, to be deposited as thick stratified beds of 

 marine and river sediments. The upland portion of Chatham 

 County is built up of mottled clays and sandy clays, probabl}* of 

 Lafayette age, quite generally covered to a depth ranging from a few 

 inches to many feet by the yellow to gray sands and sandy loams of 

 the Columbia formation. The light-gray to yellow fine sand, the 

 fine sandy loam, and the sandy clay of all of the higher elevations 

 consist of such materials, while the mottled sandy clay which out- 

 crops along the lower slopes of the ridges and is found in the deeper 

 railway cuts was probably formed as a marine sediment in Lafayette 

 time. 



On the level uplands and in the minor depressions between ridges 

 the marine deposits of the Columbia formation have been locally 

 modified because of insufficient drainage and the accumulation of 

 considerable amounts of partly deca} 7 ed organic matter. This has 

 given rise to a mucky black, dark-brown, or dark-gray surface soil, 

 varying from a few inches to 3 or 4 feet in depth. 



The county also contains along the rivers considerable areas of 

 tide-marsh lands of alluvial origin. A part of this land was for- 

 merly reclaimed and planted to rice, but this occupation has prac- 

 tically ceased in recent years. The surface of the tide marshes is 

 covered by turf or peat, or else by partly decayed organic matter and 

 silt. The subsoil is most frequently a drab or gray silt clay. It is 

 saturated at high tide and practically occupied only by swamp vege- 

 tation, but would be easily reclaimable for agricultural use. 



The immediate coast of the county is occupied by sandy beaches 

 and dunelike ridges of gray or white sand. Hollows and trough- 



[Cir. 19] 



