152 FOREST REGULATION 



2. Yield table. Pine, Site II, rotation sixty years, fully stocked. 

 Thinnings not considered. 



AGE. 



10 

 20 



30 

 40 



5 

 60 



3. The Normal Growing' Stock or Growing Stock on sixty 

 acres of Normal or Regulated Forest : 



a. By average yearly growth of ripe timber per acre. 



By Diagram Fig. 7 : r = 60 y ; Yr = 5600 ; G = 5600 X 60/2. 

 Growing Stock = 168,000 cu. ft. on 60 acres, or 2800 per acre.* 



b. Calculated from the above Yield Table by the formula 

 n (a -f- b -|- c -f- d + e + f/ 2 ) growing stock on sixty acres is : 



a = 460 c = 2250 e = 4500 



b = 1 200 d = 3400 f /2 = 2800 



On 60 acres: 14610 X io 146,100; or 2450 per acre. 



4. Actual Growing Stock on this Forest: 

 a. Calculated by Yield Tables. 



AREA AGE STOCKED 



ACRES. YEARS. IN O.I. VOLUME IN CUBIC FEET 



70 io 0.9 70 X 0.9 X 460 = 28900 



130 20 0.7 130 X 0-7 X 1200= 109200 



60 30 0.8 60 X 0.8 X 2250 = 108000 



2OO 40 O.7 2OO X 0.7 X 34OO = 476OOO 



1 50 50 0.7 1 50 X 0.7 X 45 = 472500 



40 60 0.8 40 X 0.8 X 5600= 179200 



Total on 650 acres = 1,373,800 cubic feet. 



Per acre Ga. or Actual Growing Stock = 2110 cubic feet.| 



*The usual calculations for conditions of this Growing Stock for fall 

 and spring are left but of consideration. 



$ All figures rounded off in these problems. 



