180 CONSERVATION OF GROUND WATER 



in interception and transpiration. Cutting of the broad- 

 leaved rhododendrons and laurels on another area has in- 

 creased stream flow by about 5 per cent. Cutting of riparian 

 vegetation along a stream has increased yield by about 20 

 per cent, but in the succeeding nine years, the new growth 

 has taken a gradually increasing amount of water so that 

 the yield of that basin is now just about the same as before 

 the cutting. 



In addition to these experiments, where every effort was 

 made not to disturb the soil, some experimental areas are 

 devoted to study of the effects of local logging, grazing, and 

 cropping practices on the land. In these areas, there has 

 been measurable loss of infiltration capacity and conse- 

 quent increase in overland runoff and soil erosion. 



Copper Basin, Te)in. 19 This area in the southeast corner 

 of Tennessee provides a notable contrast to the Coweeta 

 Experimental Forest and shows the marked changes that 

 can be made by land occupancy. Although the bedrock in 

 the Copper Basin is not the same as at Coweeta, it has been 

 similarly disintegrated by weathering and has formed a 

 relatively impermeable clayey soil. The Copper Basin was 

 originally covered by forest similar to that of the Coweeta 

 area. 



The copper deposits near Ducktown were discovered 

 long ago and have been mined since 1854. Smelting changed 

 the forest cover tremendously during the nineteenth cen- 

 tury. Within an area of 7,000 acres around the smelters, all 

 vegetation was destroyed by sulfur dioxide fumes, and over 

 a larger area the trees not cut for fuel were damaged by the 

 fumes. Severe erosion has resulted, especially in the central 

 devastated area; the soil has been removed, and gullies as 

 much as 25 feet deep have cut into the disintegrated bed- 

 is References: Hursh, C. R., Local Climate in the Copper Basin of Tennessee 



as Modified by the Removal of Vegetation, U.S. Dept. Agr. 



Tech. Bull. 774, 1948, 38 pp. 

 Hixson, Fred, Conservation Plan in Copper Basin Starts Tree 



Growth on Barren Land, Chattanooga Times, April 17, 1950. 



