Forest Management 13 



the term "merchantable trees,'' and the term "mature trees.'' Mer- 

 chantable trees are very often far from being mature; and mature trees 

 have often ceased to be — or are not — merchantable. 



An equal annual yield offers to the lumberjack the advantage of 

 equal and steady employment in one and the same forest or at one and 

 the same mill. 



An equal annual yield offers to the owner approximately equal an- 

 nual dividends. 



Where no yield is obtainable for a long series of years, there the 

 outlay for taxes, protection and administration will accumulate at a rate 

 deterring the owner from any attempt at conservatism. 



The disadvantages of a sustained yield where it binds the forester 

 in iron chains, are: 



1. It is impossible to take advantage of boom prices. 



2. It is necessary to cut in years of panic. 



3. Trees without increment are left uncut; trees of good increment 

 are cut where the yield is strictly sustained. Similarly, needful thin- 

 nings are often postponed; or in other cases conducted with excessive 

 severity. 



4. Valuable young growth is often left under severe pressure over- 

 head; or in other cases prematurely exposed. 



5- Seed years are not used to full advantage. 



The normal possibility, from the economic standpoint, cannot be 

 expressed by volume; it must be expressed in dollars and cents. It is 

 that sum of money which yields annually the expected or desired inter- 

 est on all capitals engaged in the forestal production. In other words, 

 it is the yield of a forest when in financial equilibrium. 'In that case, 

 no wood works at a lesser rate than at the proper indicating percentage 

 adequate to its age. 



PARAGRAPH VII. 



UTILIZATION PERCENTAGE. 



The ratio between annual cut and stumpage at hand reads, in the 

 normal forest: — 



sustained yield r i 2 2 



-. = = — . The factor — 



normal growing stock r ' i r r 



2 

 is called the utilization percentage. 'It expresses the fact that a short 

 rotation allows, when the growing stock is given, of a larger possi- 

 bility than a long rotation. Short rotations are handicapped by silvicul- 

 tural drawbacks and the production of small trees only, the demand 

 for which is restricted (firewood, spokes, axe-handles and railroad ties). 

 The utilization percentage, since it is the ratio of volumes only, has 

 little economic importance. 



