CALCULATION OF THE ROTATION FOB SISSOO AND MULBEKBY 97 

 COPPICE IN CHANGA MANGA. 



5 years old in which an excessive number of standards had been 

 left." 



Parker could have continued his argument and shown the 

 bearings of compound interest at the rate he adopts for all calcu- 

 lations of the financial returns of this plantation, viz., 4%. 



(1) At a rotation of 15 years Y= 1,606,800 c. ft. stacked. 



Multiplying by Ks. 6 per cent. c. ft. 



stacked =96,408 rupees. 

 Add 4% compound interest for 

 5 years, i.e., 

 x 1-2167 =1,17,299 Eupees. 



(2) At a rotation of 20 years Y= 1,907,100 c. ft. stacked. 



Multiplying by Es. 8 per cent. c. ft. 



stacked =1,52,568 rupees. 



. * . An extra annual profit of Es. 35,269 is made by lengthen. 

 ing the rotation to 20 years. 



All the standard methods of calculating the yield will be found 

 in Schlich's " Manual of Forestry " and in Eecknagel's " Theory 

 and practice of working plans." It is only proposed here to deal 

 with such methods as have actually been used in practice and as 

 are recommended as suitable to our work. 



This method is adopted in working circles with a periodic 

 block frame work managed under the shelterwood system. The 

 final yield in the regeneration area or periodic block no. I is 

 calculated in volume and in the rest of the area intermediate 

 yields are realised by area. 



Yield = v+ ' ix l> 



P 

 Where v = volume of growing stock, of P. B. I. 



i=C. A. I. of the growing stock 



p = number of years in the period. 



7 



Method of 

 calcula- 



By volume 



a J id < j rectl 

 Based on 



periods. 



