Periodical Literature. 499 



values. The volume increment which takes place as the annual 

 ring can have only the unit value which pertains to the age class 

 or dimension class on which it occurs ; if the increment occurs on 

 wood worth 5 cents a cubic foot it can not be worth more than 5 

 cents, except as with the increase in diameter an increase in use 

 value and in money value comes about. Multiplying the volume 

 increment in each age class with the value pertaining to that age 

 class and adding up, one secures the value of the increment of 

 the management class. This value can be influenced by influenc- 

 ing, through thinnings, etc., the volume increment. 



Regretting the unfortunate mixing up of the terms "value in- 

 crement" and "price increment," the latter dependent on market 

 fluctuations, without any change in the sale object itself, he points 

 out that in the forester's value increment or quality increment, 

 the volume increment is involved: by the mere year's increment 

 suddenly without any effort of the manager the whole tree re- 

 ceives a higher value per cubic foot — a value increment. 



It is not 100 year old wood, which comes to sale when a 100 

 year old stand is cut: only the first year's smallest growth is 100 

 years old, each annual layer, however, has experienced a value 

 increment, which in a way exhibits the progess of value increment 

 in all I to 100 year old stands of a management class, and the 

 amount of this increment is expressed by the difference of the 

 value of the oldest age class and the value of the current incre- 

 ment. 



In a tabulated example referring to given market and price 

 conditions, in a pine forest on III site the value of the 80 year 

 stand is figured as 12,500 cubic feet X 4-5 cents=$562 ; the values 

 of the increment of each 10 year age class, calculated with the 

 price per unit of the age class, added up, give $356, hence the 

 value (quality) increment of the whole management class is 562 

 — 356=$2o6. Similarly, the value of a spruce management class 

 in its oldest member at 80 years is $1,336, the value of the age 

 class increment adds up to $706, hence the value (quality) incre- 

 ment of the management class (normal stock) is $630. In both 

 cases this value is much less than half the stock value of the oldest 

 age class. In these examples, there are of this total annual value 

 increment of the normal stock, in case of the pine, 63% repre- 

 sented by increment value, 37% by value increment, in case of the 

 spruce, 53% by increment value, 47% by value increment. 



