SOIL EROSION IN THE SOUTH. 23 
In navigable streams the deposition of this sediment in the stream 
bed causes a filling or shifting of the channel and the formation of 
bars. The Roanoke River is reported to carry 3,000,000 tons annu- 
ally, the Alabama 3,039,900 tons, the Savannah 1,000,000 tons, and 
the Tennessee 11,000,000 tons, while other rivers carry like amounts. 1 
This indicates the extent of the loss of soil material, together with 
the additional losses just described. 
The economic aspect of soil erosion has been discussed by a number 
of authorities, 2 who agree that tfye United States is losing millions of 
dollars each year from this cause. The report of the National Con- 
servation Congress, 1909, 3 states that in the United States there are 
6,076 square miles of farm land, or 3,888,640 acres, devastated by 
soil erosion an area which is equal to 100,000 farms of nearly 40 
acres. 
SUMMARY. 
Soil erosion is a natural process, tending to level the land. Gen- 
erally under natural conditions it is slower than the formation of 
soil material from the parent rocks. 
Destruction of the natural growth and clean cultivation on hilly 
land, without protection against erosion, results in the removal of 
the soil material by water more rapidly than it is formed and in a 
very irregular manner. 
Owing to the climatic and soil conditions the South is especially 
susceptible to excessive erosion. The economic conditions and type 
of agriculture of this section also contribute to the excessive erosion. 
Methods of prevention should be practiced wherever hilly land is 
used for crops. Terracing is the best and most efficacious method, 
but should be supplemented by deep plowing and the incorporation of 
organic matter when permissible. 
The agricultural problem involves the adoption of proper crop 
rotation in connection with preventative methods best suited to soil 
conditions and crop production. 
The reclamation of eroded land is possible, but requires careful 
attention and patience. The use of such land for forestry is com- 
monly advisable. Nature effects reclamation, but the process is 
slow and tedious. 
The losses annually to agriculture and in expenses incurred at 
power sites and in maintaining navigable channels are enormous, 
and constitute one of our greatest national wastes. 
i Amer. Rev of Rev., 89, 439 (1909). 
2 See: N. S. Shaler, Economic Aspect of Soil Erosion, Nat. Geog. Mag., 7, 328-38 (1896); T. C. Chamber- 
lain, Soil Wastage, Proc. of Conf. of Governors on Conservation, House Doc. 128, pp. 75-83 (1908); Top. 
Sci. Mo., 73, 5-72 (1908); W. W. Ashe, Waste from Soil Erosion in the South, Amer. Rev. of Rev., 39, 439- 
43 (1909). 
8 Report Nat. Con. Cong., S. Doc., No. 676, 60th Cong., 2d sess. (1909). 
WASHINGTON : GOVERNMENT PRINTING OFFICE : 1915 
