1488 



A NATIONAL PLAN FOR AMERICAN FORESTRY 



stated here that forest planting, because of its high initial cost, is the 

 forest land manager's last resort. Lands which will restock naturally 

 within a reasonable period should be permitted to do so, thus confin- 

 ing the expense of planting to those lands which otherwise would 

 be idle for a longer period than can be justified. 



An estimate by regions of the area that will satisfactorily restock 

 naturally if properly protected from fire, insects, and disease is 

 given in table 2. In 20 years approximately 47 million acres, and 

 in 40 years approximately 68 millions acres of the 138 million acres 

 of the present unproductive land shown in table 1 are expected to 

 restock. There remain practically 91 million and 70 million acres 

 which will not restock in 20 to 40 years respectively. 



TABLE 2. Estimate of area that will restock naturally and satisfactorily l in 20 and 



40 years by regions 



1 "Satisfactory" stocking is defined as 40 percent or more of full stocking. 



WHY PLANTING SHOULD BE DONE 



There are three principal reasons for attacking the unproductive 

 land problem through the agency of forestation. 



1. Influence of forested land on watershed protection. 



2. Need for more extensive local timber production to meet future 

 requirements and to stabilize wood-using industries. 



3. Value of forestation in the solution of social and economic 

 problems arising from unwise land use. 



PLANTING FOR WATERSHED PROTECTION 



The effectiveness of forest cover in watershed protection has been 

 amply made evident by general observations and to a lesser extent 

 by experimentation under controlled conditions. For a full discus- 

 sion of the character and extent of run-off and erosion that menace 

 two of our most essential resources, soil fertility and water supply, 

 reference should be made to the section "Watershed and Related 

 Forest Influences". The problem as here reviewed is one both of 

 erosion control and stream-flow regulation. 



EROSION AND ITS CONTROL 



The establishment of a forest cover on eroding areas by reforesta- 

 tion is a comparatively simple and effective means of controlling 

 erosion. Even as a remedy for the most severe type of erosion, 

 known as "gullying," which exposes sterile subsoil and leaves steep 

 banks that easily slough away, reforestation is surprisingly successful. 



