106 PRACTICAL FOREST MANAGEMENT. 



i =C. A. I. of old group 

 p = l/3rd the rotation. 



If the growing stock is not normal, then various adjustments 

 must be made as described in the text-books. 44 The method is not 

 at present particularly suitable for Indian conditions and requires 

 yield tables in order to find out whether the sum of volumes of the 

 two groups is normal or not. It also requires the enumerations of 

 the forest in diameter classes varying with each different quality 

 class, which is scarcely practicable. 



3y are*. This method should be used for forests managed under the clear 



felling system. Each compartment is given a nett reduced area 



according to quality and the 



Reduced a*ea of the Worltinq Circle 



Yield^ 



rotation 



Coppice felling yields are always regulated by area ; regeneration 

 fellings in P. B. I. may, under certain exceptional circumstances, 

 be regulated by area as is the case in the Chir Working Circle of 

 North Garhwal. This regulation by area formerly existed for 

 P. B. I. of the Conversion Working Circle of Haldwani and 

 Eamnagar but was found unsatisfactory and has been replaced by 

 a volume yield. 



Fellings in selection forests have generally been regulated by 

 area sometimes with a volume or tree limit in addition, a most 

 unsatisfactory arrangement. 



In protection forests regulation of the yield by area should 

 continue to be the ordinary procedure but elsewhere in forests 

 worked under selection a volume yield should be insisted on. In 

 no case should an atte.mpt be made to limit the yield to a certain 

 area plus a certain volume combined, as this means that either the 

 area is worked over and the volume not obtained or the volume is 

 obtained over part of the area and the rest then left unworked 

 altogether, as the next year a diffarent area has been prescribed 



for fellings. 



44 Theory and "Practice of Working Plant RECKNACEL. 



