1522 A NATIONAL PLAN FOR AMERICAN FORESTRY 



Originally almost unbroken, the forest stands have been reduced by 

 fire, grazing, lumbering, and clearing for agriculture by approximately 

 75 percent in the South and by an even greater proportion in the 

 North. 



The erosion problem here is very largely the consequence of im- 



aer agricultural practices. It has resulted in part from cropping 

 that never should have been cleared and in part from using im- 

 proper cropping methods on good agricultural land. Principally as a 

 result of these two practices about one sixth of the agricultural area 

 has already been abandoned and active erosion is continuing on about 

 one fourth of this abandoned land. 



Special measures to check erosion are needed now on upwards of 

 1 million acres of the bluff lands, and unless present bad practices are 

 quickly corrected will be needed on an even larger area. The volume 

 of soil being eroded from these areas each year is inconceivable. A 

 single rain on experimental plots near Holly Springs, Miss., for exam- 

 ple, removed soil at the rate of 23 tons per acre from cultivated land 

 with a 10 percent slope. Studies in southwestern Wisconsin have 

 resulted in an estimate that an area of 10,000 square miles in Wiscon- 

 sin and Minnesota contributes 15 million tons of silt to the Mississippi 

 River annually. In both sets of experiments erosion from forested 

 soils was insignificant compared with that from barren or cultivated 

 soils. While these figures may or may not be extreme, they establish 

 clearly the importance of erosion control on bluff lands if the Missis- 

 sippi River silt problem is to be solved. 



The same studies showed the effectiveness of the forest cover in 

 controlling run-off. The percentage of the precipitation that ran off 

 immediately from cultivated plots as compared with that from forested 

 plots was about 130 times as large in Mississippi and about 12 times 

 as large in Wisconsin. 



The situation on forested lands, while far from satisfactory, is in 

 general not wholly bad. Particularly in the South, fires occur com- 

 monly in the bluff lands and destroy the leaf mold and litter so neces- 

 sary to watershed protection. In the State of Mississippi as a whole 

 the acreage burned over annually averages more than 40 times the 

 allowable burn. The percentage burned in the bluff lands is not much 

 below the State average. Timber cutting, while usually falling short 

 of devastation, has been too heavy to permit the forest to exert its 

 full watershed-protective influence, and grazing has injured the forest 

 cover on many areas. 



Solution of the erosion and flood problems of the bluff lands, essen- 

 tial both locally and nationally, appears to require (1) lifting from 

 agricultural use land that is submarginal for that use; (2) reforesting, 

 by planting, the 650,000 acres of land on which erosion will otherwise 

 continue; (3) providing adequate fire protection on timberlands; and 

 (4) installing special mechanical erosion checks where necessary. 



There is little hope of obtaining proper watershed conditions on 

 this land in private ownership, because the expense incidental to 

 proper management will not be returned as a direct financial profit 

 to the individual owner. To obtain such conditions will necessitate 

 public acquisition of a large acreage of submarginal farm and forested 

 land. On the timberlands that remain in private ownership, fire 

 protection should be materially strengthened, through public aid and 

 extension. 



