FOREST ECONOMY. 2OI 



condition, which the forester recognizes in the 

 "normal forest," the standard by which he meas- 

 ures his actual forest and to which he desires, as 

 nearly and as quickly as circumstances permit, to 

 bring his actual forest. The latter will usually be 

 found abnormal in some one direction, or in several 

 directions, and hence make the ideal conduct im- 

 possible. The object of forest regulation, then, is 

 to prepare for the change of an abnormal forest 

 into a normal forest. 



In simplest terms, the normal forest is a forest in 

 such condition that it is possible to harvest annually 

 forever the best attainable product, or to secure con- 

 tinuously the largest possible revenue. The concep- 

 tion and schematic description of the normal forest 

 we have already elucidated on p. 1 28 ff . It was there 

 shown that such a forest must contain as many 

 stands, varying in age by years or periods, as there 

 are years in the rotation (r= normal felling age) 

 i.e. normal age classes must be present, so that an 

 annually equal normal felling budget (ri= /) might 

 be harvested, the reproduction being looked after, 

 and the best possible, i.e. normal accretion (/'), being 

 secured by silviculture. As a result of these two 

 conditions the normal stock (%$") would be present, 

 which would permit the desired annual sustained 

 yield management. We found that the normal 

 stock, varying in actual amount, of course, accord- 

 ing to species, site, silvicultural system, and espe- 

 cially length of rotation, is found by summing up 



