Zi2 PHYSIOGRAPHY AND GEOLOGY OF THE COASTAL PLAIN PROVINCE. 



Darton" gives the following description of the swamp soils in the 

 Norfolk quadrangle. 



"The soils of the swamps vary from pure peat to clayey loam. Two 

 leading varieties are recognized, the 'Juniper' or 'light' swamp, and the 

 'black gum' or 'dark' swamp. The first is nearly pure peat, consisting of 

 a brown mass of vegetal fragments derived from the juniper or white 

 cedar, which is the characteristic tree of 'light' swampy areas. The thick- 

 ness of the deposit is often 8 to 10 feet. From 75 to 95 per cent of the 

 material is organic. When such land is cleared and drained the peat cakes 

 and hardens so that it resembles charred wood. Land of this sort is 

 practically worthless. The black gum swamp deposits which have been 

 laid down in various portions of the Dismal and other swamps and which 

 bear a forest of cypress, .black gum, and red maple, are well adapted to 

 agriculture in most cases. This soil contains a large amount of organic 

 matter which is mainly in its upper portion. When it is properly drained 

 and cultivated the amount of organic matter gradually diminishes, but it 

 has been found in the drained areas that after being under cultivation 

 for fifty years the soil still retains enough organic matter to remain black 

 in color. The organic matter furnishes nitrogenous materials to plants, 

 so that the soil is a rich one, but its disposition to retain moisture renders 

 it rather slow for the raising of early vegetables. The soils are also notably 

 acid, which has to be neutralized by repeated applications of lime. The 

 percentage of clay in the stvamp soils is large, for the sluggish drainage 

 in the swampy areas does not bring much sand, and the principal inorganic 

 sediments are very fine flocculent clayey materials. This character greatly 

 retards artificial drainage of the region, so that in reclaiming swamp lands 

 numerous ditches and extensive tiling are necessary * * * *^ There are 

 extensive areas of the swamp which can be economically drained and which 

 have rich and lasting soils, and the region has good prospects of being 

 valuable agriculturally in the future. It is not expected that the soils will 

 be available for truck farming to the same extent as the dry plains of the 

 surrounding region, but they will yield crops of many important staples." 



oNorfolk Folio, No. SO, U. S. Geol. Survey, 1902, p. 4. 



