66 FOREST VALUATION 



a. The regulated or normal forest. 



1. Premises: Area, 16,000 acres. 



Method, clear cut, and plant, even age stands. 

 Rotation, 80 years. 



Thinnings every 10 years, beginning when the stand is ten years 

 old, the last at seventy years. 



2. Condition of forest in spring just after planting: 

 Two hundred acres just planted, growing stock o years old. 

 Two hundred acres growing stock t year old, etc. 



Two hundred acres 79 years old, or r-i years old. 



3. Yearly work, expense and income on this forest : 

 Two hundred acres are cut, income 200 x Yr. 



Fourteen hundred acres thinned, income T^^ (200), T,,, (200), 

 T.,„ (200), etc. 



Two hundred acres are planted, 200 x c. 



Sixteen thousand acres protected and cared for in road building 

 and other improvements, taxes paid, cost 16,000 xe. 



Sixteen thousand acres growing stock pay rent of land 16,000 

 X Sc (.op). 



4. A proper sample of this regulated forest would contain 80 

 acres, one acre just planted, one acre with one year old stuff, one 

 acre two years old, etc. to one acre 79 years old, taken from the 

 oldest stands. Whatever is true as to the average value of this 

 sample of eighty acres appHes to the whole forest of 16,000 acres 

 so that if the growing stock on the sample eighty acres is worth 

 fifty dolars an acre on the average, the growing stock on the 16,000 

 is worth fifty dollars an acre average. 



b. Expectation value of the growing stock of the regulated 

 or normal forest. 



For sake of simplicity the rotation is assumed to be only ten 

 years so that the sample of the regulated forest contains ten acres. 

 Diagram, Fig. i, illustrates this 10-acre sample and indicates the 

 present value of yields, Yr, and thinnings, which are to be obtained. 



The yearly work and expense and income on this lo-acre sam- 

 ple are: 



One acre cut, income Yr. 



One acre thinned, when stand is 4 years old, income T^. 



One acre planted, costs c. 



Ten acres protected, cared for, taxes paid, expenses 10 x e. 

 Ten acres of growing stock pay rent on the 10 acres of land, cost 

 10 X Sc (.op). 



