320 DETERMINATION AND REGrLATION OE THE YIELD. 



then the method is one of considerable merit. It enables the 

 forester to arrange the grouping of the age classes and cutting 

 series in the most desirable way and to do justice to all other 

 s^'lvicultural requirements, since it leaves him an entirely free 

 hand in the selection of the woods to be cut. 



The method is applicable to all sylvicultural systems, but 

 the determination of the increment and growing stock involves 

 much labour. Under it, a forest is gradually led over into the 

 normal state, though perhaps not for a considerable period of 

 time ; the difference between the real and normal state will, 

 after the first rotation is passed, be so small, that it can be 

 neglected. 



The sample working plan given in Appendix Y., page 890, 

 has been based upon the formula of this method. 



2. Hundeshafjen's ISIcthod. 



a. Drscripfion of the MelJ/o/I. 

 Hundeshagen's method of determining the yield is based 

 upon the idea, that the real yield must bear the same pro- 

 portion to the real growing stock, as that existing between the 

 normal yield and normal growing stock ; he thus obtains the 

 equation — 



and 



i; = G, X ~" . 



In words, the real yield is equal to the real growing stock 

 multiplied by the normal yield and divided by the normal grow- 



r,, 



real growing stock is multiplied, the " utilisation per cent." 

 (More correctly this indicates only the rate of utilisation, 



whereas the utilisation per cent, is -./^ X 100.) 



L^,^ 



The normal yield is placed equal to the normal increment, 

 or equal to the contents of the oldest age gradation in a 



