324 DETERMINATION OF THE YIELD. 



understands that actually present in the forest) is equal to the 

 normal growing stock, then his formula goes over into 



rxl 



2 



The formula gives, therefore, the correct yield, provided the 

 increment is normal. 



If the actual growing stock is smaller than the normal, say 



x>_?'Xl fhpTi flip 



yPttl ^-^ r\~~ 9 vllt/Xl L11C 



rxl_ 



O 2^7' 7* 



Yield = = 1 = I , 



r r r 



"2 2 



which means, that less than the increment is cut. 



Supposing that the real growing stock is greater than the 

 rxl 

 "2" 



rxl 



T T ~r i & 



normal: real G=- --+x; then, 



r r 



2 2 



more than the increment will be cut, so that the surplus of 

 growing stock will gradually disappear. 



All these assumptions depend, however, on the supposition 

 that the normal increment is laid on. If the increment i& 

 deficient, the abnormal state may be further increased, until 

 the increment has reached its normal size. 



The merits of the method are approximately those of 

 Hundeshagen's method. It introduces an additional inaccu- 

 racy by being based on the assumption that the normal 



I x r 

 growing-stock is = . On the other hand, the normal 



growing stock and normal yield need not be determined ; in 

 other words, the method can do without yield tables. It is only 



