CURRENT ANNUAL INCREMENT 451 



Now, in the pole forest stages of any crop, the current 

 annual increment per acre almost invariably far exceeds the 

 average annual increment. 



But the current annual increment per acre will usually 

 reach its maximum towards the end of the pole forest stage, 

 after which it decreases ; it will continue longer in the case 

 of shade-bearing trees which can be left thicker on the 

 ground than is the case with light-demanding trees which, as 

 the principal height growth is attained, require to be freely 

 thinned. 



On good soil the maximum current annual increment per 

 acre is attained sooner than on poorer soil. 



The culmination of the current increment per individual 

 tree is attained long after the culmination of such increment 

 per acre. It is most necessary to avoid confusion on this 

 matter, and to remember that the latter is largely governed 

 by the number of trees per acre. 



However, the average annual increment attains its 

 maximum a long time after the date of the culmination of 

 the current increment ; and it will continue to rise for so 

 long as the current annual increment exceeds the average 

 annual increment. 



But the current increment, when it ceases to be equal to 

 the average annual increment, decreases annually much more 

 quickly than the average annual increment. 



Practically speaking, however, the percentage increment 

 is of far more value than the mere amount of the current or 

 the average annual increment, if the treatment of any 

 particular crop is under consideration. 



Now, besides the increment, or the percentage increment 

 in contents, that is taking place, or is likely to take place in 

 the near future, it is of the greatest importance to consider, 

 also, the increment in quality or in the price per foot cube 

 that may be anticipated. 



2. Increment in Quality. 



The increment in quality or money value per foot, may be 

 conveniently expressed as a percentage on the present price. 



