THE WOOD CROP 221 



Destruction of forests results in floods and dry rivers. 

 The severe floods of the Ohio river of recent years are 

 due to the deforested mountain lands that it drains. The 

 water all runs off rapidly instead of being held back. 

 The losses caused by the floods direct and as a loss of 

 water power would pay for reforesting the mountains. 



Possibly it is the fact that forests at the source keep 

 up the summer flow of streams that has led to the errone- 

 ous conclusion that forests increase rainfall. Or, perhaps, 

 the error came from the observation that where forests 

 occur there is usually a good rainfall. The rain is the 

 cause of the forest not the result of it. 



209. Conservative Lumbering. This differs from ordi- 

 nary lumbering in that: 



(1) The forest is treated as a crop that must produce 

 successive and regular harvests, rather than as a mine 

 to be exhausted once for all. 



(2) Small trees are not cut when they are needed to 

 renew the growth. 



(3) Attention is given to keeping the stand neither 

 too thick nor too thin. 



(4) The tree weeds, broken and diseased trees, are 

 removed to make room for good trees. In ordinary lum- 

 bering, the tree weeds are the ones that are left to reseed 

 the area. 



(5) Lumbering is conducted in such a way as to injure 

 the young growth as little as possible. 



(6) In some cases, seeds or young trees are planted. 

 This is expensive and is usually not necessary if a forest 

 is well handled. 



(7) The forest is protected from fire. 



