VARIOUS SYSTEMS OF FOREST MANAGEMENT. 57 



financially much more profitable than the former large 

 ones. 



2. The principle of the maximum growth of the 

 trees. In accepting this principle, the time of cutting 

 the trees has arrived as soon as the yearly average in- 

 crease of the wood in the trees has reached its highest 

 point. 



The average maximum growth of a tree is found by 

 dividing the entire mass of the tree by the number of 

 years of its age. The current or yearly increase of the 

 mass shows the relation of the quantity of wood grown 

 during the year in question, to the existing whole mass 

 of the tree. 



3. The principle of producing the maximum of value. 

 According to this principle, the lot is cut as soon as 

 the trees have reached the age at which they bring the 

 highest prices in the gross amount. The average 

 maximum of value ia found in the same way as the 

 maximum of growth. 



But these two latter systems suffer the same fault of 

 having their cutting periods too far apart, thus pre- 

 venting the capital invested from being made profitable; 

 for trees do not continually increase in their growth at 

 the same rate in which the capital invested accrues with 

 compound interest. They grow only during the first 

 sixty or seventy years in a proportion adequate to 

 straighten their debit account, and leave then a hand- 

 some profit. Later this proportion changes very much 

 to the detriment of the capital. For instance : A forest 

 of Conifers furnishes at the age of one hundred years 

 not much more wood than double the quantity which it 

 would have yielded at the age of sixty years, while the 

 sum representing the value of the wood at the forest's 

 age of sixty years, would, with compound interest, in- 

 crease during the next forty years to at least four times 

 its amount. 



