40 



BULLETIN 55, U. S. DEPARTMENT OF AGRICULTTJBE. 



that it b^ins to decline. On the flat the maximum rate of volume 

 growth is reached at an age between 50 and 85 years, after which it 

 slightly declines and remains stationary until a very old age. 



The increment in cubic feet becomes noticeable much later than 

 the growth in height or diameter; namely, when the tree is 40 or 50 

 years old. This is still more marked m the case of the increment in 

 board feet. Thus, up to 70 years, even on the hardwood slope, where 

 the growth is fastest, no increment in board feet is noticeable. It 

 reaches its highest rate at the age of 125 years, and continues at a 

 fairly steady rate practically to the limit of the physical Ufe of the 

 tree. On the flat the increment in board feet starts at about 80 and 

 in the swamp at from 90 to 95 years. 



Table 19. — Total voluiiu, in cubicfeet, of balsam Jii- in N'cw York, on the basis of diameter 



and height. 





Height of tree (feet). 



Diswneier breast high (inches). 



20 



30 40 



50 



60 



70 



SO 





Total volume (cubic feet). 



3 



, 0.54 



.96 

 1.48 



0.81 

 1.43 

 2.21 

 3.15 

 4.24 













4 



1.91 

 2.95 

 4.19 

 5.63 

 7.25 













3.60 

 5.23 

 7.01 

 9.01 

 11.19 

 13.59 

 16.10 









6 . 



6.24 

 8.37 

 10.76 

 13.38 

 16.23 

 19.25 

 22.38 

 25.71 

 29.12 

 32.77 

 36.53 



7.24 

 9.72 

 12.51 

 15.55 

 18.86 

 22.36 

 26.06 

 29.94 

 33.98 

 38.14 

 42.52 







11.07 



8 1 



14.24 



9 ■ 







17.71 



10 i 



1 " 



21.47 



il 1 





25.50 



12:;:; \ 





29.72 



13 1 







34.14 



14 ' 









38.74 



15 . . : 1 







43.59 



16 







48.59 



1 









Table 20. — Total volume, in cubicfeet, of balsam fir in Maine, on the basis of diameter 



and height. 





Height of tree (feet). 



Diameter breast high (inches). 



40 



50 



60 



70 



80 





Total volume (cubic feet). 





5.68 

 7.22 

 8.87 



7.20 

 9.17 

 11.26 

 13.20 

 15.77 



8.76 

 11.12 

 13.75 

 16.49 

 19.40 

 22.38 

 25.44 

 28.48 

 31.62 

 34.52 



10.34 

 13.22 

 16.33 

 19.66 

 23.15 

 26.83 

 30.58 

 34.35 

 38.14 

 42.03 





8 



15.33 



9... 



18.98 



10 



22.91 



11 





27.03 



12 





31.42 



13 





35.91 



14 





40.45 



15....;...: ;.:::;:;;;;;:.:::::::; 



45.06 



16 



49.71 



i 





