GE IN NORMAI, FOREST 



67 



2. Adding the values of the growing stock of the 10 acres 

 gives the value of the growing stock for the entire sample of 10 

 acres and dividing this sum gives the average value per acre for the 

 sample, and also of the regulated forest. 



Fig. I. Diagram representing 10 acres (r acres), a sample of a forest regulated on a 

 ID year rotation, indicating the age of the growing stock on each acre; the present value of 

 the final yield (Fr) from each, and the present value of the thinnings expected from each 

 acre. Since » on the acre of 7 year old stuff is to be cut in 3 years, its final value, or 

 stumpage value is discounted for 3 years. On the several acres 4, or more years old, no 

 further thinning is to be expected, but the stand 3 years old will furnish a thinning next 

 year, and hence the value of this is discounted for one year, etc. 



Since the general formula for expectation value of growing 

 stock reads: 



"Ge: 



Yr + Tad.op---')— (Sc4- E) (Lop---"'— i) 

 I. op'-'" 



the value of the several acres beginning with the oldest stand may 

 be written : 



°Ge: 



Yr-fo— (Sc + E) (Lop---'— I) 

 I. op'--' 



Note: — The thinning from this acre has been taken and no further 

 thinning is expected. 



