70 THE THEORY AND PRACTICE OF WORKING PLANS 



rotation is 60,200 board feet per acre, the minimum (Site III) 

 33,600 board feet per acre. 



Per acre 



Site quality I < . . . 60,200 board feet 



II 46,900 " 



in 33.600 



On the basis of site quaHty I the per cents of the other site 

 qualities would be : 



Site quahty I i . 00 



II 78 



HI 56 



These are the factors of reduction to the common site quality 



(I). 



If, in the above instance, the actual area of 10,000 acres was 

 composed equally of each site quaHty (I to III), then the 

 reduced area would be : 



Site quahty I, original 3,334 acres, reduced 3,334 acres. 

 Site quaHty II, original t,,S33 acres, reduced 2,600 acres. 

 Site quaHty III, original 3,333 acres, reduced 1,866 acres. 



Total, 10,000 acres, reduced 7,800 acres. 



The annual or the periodic cutting area is, therefore, varied 



according to the site quaHty or qualities in the area allotted. 



„ ,, , ..• reduced area 7800 



E.g., the annual cuttmg area = -. = -^ — =130 acres. 



^ ' ^ rotation 60 ^ 



Similarly the periodic cutting area =130X20 = 2600 acres. If 



these 2600 acres were all to be distributed among site quaHty 



II it would actually require: 



2600X1.28 = 3328 acres; 

 for, from the above table of percentages, it requires: 



1.28 acres of site quaHty II to equal i acre of site quaHty I. 

 1.79 acres of site quality III to equal i acre of site quaHty I. 



