200 



CHAPTER II. 



THE ROTATION. 



BY rotation is understood that period of years which elapses 

 between the formation of a wood and the time when it is finally 

 cut over and regenerated. 



The end of this period, that is to say the age of the wood 

 when cut over, is called the " final age." If it coincides with 

 that which is considered the one best suited to the system of 

 management, it is called the " normal " final age ; if a wood 

 has, for one reason or another, to be cut over at a different 

 age, the latter is called an " abnormal " final age. 



The determination of the rotation is one of the most 

 important measures in forest management. At the same time 

 the rotation depends entirely on the various objects of manage- 

 ment ; hence it differs with every change of conditions. In 

 economic forestry the following deserve to be distinguished : 



1. The financial rotation. 



2. The rotation of the highest income. 



3. The rotation of the greatest volume production. 



4. The technical rotation. 



5. The physical rotation. 



Each of these may be indicated by the objects of manage- 

 ment, and it is necessary to explain them in some detail. 



1. The Financial Rotation, 

 a. Calculation of the Financial Rotation. 



By the financial rotation is understood that under which 

 a forest yields, if calculated with a given per cent, and 



