NORTH-CAROLINA GEOLOGICAL SURVEY. 



is required to the open ground prairie will be not less than 

 140 to 150 tons to the acre. When this expense is added to 

 the expense of drainage, it is evident that in a country where 

 land is cheap it would not be economical to expend so much 

 money and labor to create as it were a soil adapted to the 

 better class of vegetables. 



12. The effect of cultivation of soils composed mainly of 

 vegetable matter and marine sand, is to consume so much of 

 the former that the latter becomes in its turn predominant, 

 and even after a few years' cultivation only, the white sand 

 shows itself through and upon the surface of the black vege- 

 table matter, and soon afterwards it appears in sufficient 

 quantities to form white ridges over the cultivated field. 

 When this takes place, the soil has already begun to exhibit 

 unmistakable evidences of partial exhaustion. 



The soils in which vegetable matter predominates, apper- 

 ently in great excess, not injuriously however, prevail orer 

 large tracts or areas in the eastern counties, and are beginning 

 to be esteemed the most valuable lands of any in North- 

 Carolina. They are not confined to one or two counties, but 

 may be found in most of them which lie east of the Wil- 

 mington railroad. They also prevail in the south-eastern 

 section, especially in New Hanover and Columbus. 



Some of the tracts are classed as pocosin and swamp lands, 

 but they agree in having a very large percentage of veget- 

 able matter, and in being also thoroughly wet and frequently 

 covered with water, I have found that there is no constant 

 percentage of vegetable matter where different and distant 

 tracts are compound together. It is as variable as the clay 

 or sand in argillaceous and sandy soils. There is also a 

 variableness as to its condition; it is often perfectly disorgan- 

 ized and presents a compact appearance when cut into blocks ; 

 or it may be in the condition of coarse fibres with their tex- 

 ture or structure perfectly preserved. In the first case, it is 

 in the proper condition for cultivation, and the latter, it has? 

 not passed into that state and condition which is fitted for 

 the nutrition of the cereals. The coarse vegetable fibre pre- 

 dominates in the open prairie grounds of Carteret, and the 



