Table 3« Tree gro wth by decades 9 expressed in board 

 feet log sc ale and c ubic feeto 



Year oooooeeoooosoooooooao 



1900 



1910 



1920 



1930 



Diameter,, top end of 



log *" XllCheS oooeooooooo 



6 



7 



8 



9 



Volume,, Scribner Decimal 

 C rule - board feet O0OO0 



20 



30 



30 



40 



Volume - cubic feet oooeoo 



4o0 



5*3 



6,7 



8o3 



Percent increase in volume by decades 9 board- foot basis? 1900-1910,, 

 50 percent; 1910-1920 5 percent; 1920-1930^ 33 percent e 



Percent increase in volume by decades 9 cubic-foot basis; 1900-1910 5 

 32 percent; 1910-1920 s 26 percent; 1920-1930^ 24 percent <> 



Evidently the percent increase in volume on a cubic-foot basis is much more 

 meaningful than the increase shown by the board-foot basis B According to 

 the board-foot basis,, the tree grew by leaps and bounds during the first 

 decade 5 then stopped growing for one decade s and in the next decade again 

 leaped ahead Actually 5 the rate of volume growth was decreasing each 

 decade as the ©ubic-foot basis shows e 



It might also be mentioned., in passing ^ that since the Scribner rule 5 as 

 well as many others^ gives high overruns for small logs it naturally 

 follows that small logs are so badly underscaled that they cannot be 

 handled profitably The end result is poor utilization of top logs in 

 large trees c The use of young timber is also penalized,, and though this 

 may be fortunate in some cases s it is unfortunate in others* As time goes 

 on and the supplies of virgin timber wane^ more and more dependence must 

 be placed on young forests,, 



C0WERTHTG CUBIC FEET TO OTHER TOUTS OF MEASURE 



Log volumes in cubic feet can be converted to the unit of measure appropri- 

 ate to each manufacturing plant with often less uncertainty and difficulty 

 than is now the case in converting board feet log scale to board feet of 

 lumber 5 board feet log scale to cords 9 or board feet log scale to units of 

 pulp chips or to other measures 



The all-important question that sawmill men will ask when cubic-foot scaling 

 is proposed iss "What converting factor must we use? How many board feet 

 of lumber will a cubic foot of logs produce?" 



-12- 



