36 



BULLETIN 55, U. S. DEPARTMENT OF AGRICULTURE. 



DIAMETER GROWTH. 



Balsam fir makes its most rapid growth in diameter between the 

 ages of 25 and 70 years, during which time the average rate is about 

 0.11 of an inch a year, or 1 inch in 9 years. On less favorable situa- 

 tions it grows at the rate of about 1 inch in 10 years. After the sev- 

 entieth year the diameter growth begins to decline, and at 75 years 

 the current annual growth falls below the mean annual growth. 



Tables 13 and 14 give the growth of balsam fir in diameter on differ- 

 ent stations in the Adirondacks . 



Table 13. — Diameter growth, in inches, of balsam fir in New York, on the basis of age. 





Hardwood slope. 

 (Based on 277 trees.) 



Flat. 

 (Based on 246 trees.) 



Swamp. 

 (Based on 158 trees.) 



Age (years). 



Diam- 

 eter 

 breast 

 high. 



Growth 

 in di- 

 ameter 

 every 

 5 years. 



Annual 

 growth 



in di- 

 ameter 

 within 



5-year 

 period. 



Diam- 

 eter 

 breast 

 high. 



Growth 

 in di- 

 ameter 

 every 

 5 years. 



Annual 

 growth 



in di- 

 ameter 

 withui 



5-year 

 period. 



Diam- 

 eter 

 breast 

 high. 



Growth 

 in di- 

 ameter 

 evary 

 5 years. 



Annual 

 gi-owth 



in di- 

 ameter 

 within 



5-year 

 period. 



10 



0.4 



.8 



1.3 



1.9 



2.6 



3.^ 



4.0 



■ 4.7 



5.4 



6.0 



6.5 



7.0 



7.4 



7.8 



8.2 



8.5 



8.9 



9.2 



9.5 



9.8 



IjO.l 



10.4 



10.7 



11.0 



11.3 



11.6 



11.9 



12.2 



12.5 







0.4 



.8 



1.2 



1.7 



2.3 



2.9 



3.6 



4.3 



4.9 



5.5 



6.0 



6.5 



6.9 



7.2 



7.5 



7.8 



8.1 



8.3 



8.6 



8.9 



9.1 



9.4 



9.6 



9.9 



10.1 



10.3 



10.5 



10.8 



11.0 







0.3 

 .6 

 1.0 



1.4 

 1.8 

 2.3 

 2.8 

 3.3 

 3.8 

 4.4 

 4.9 

 5.4 

 5.8 

 6.1 

 6.5 

 6.8 

 7.1 

 7.4 

 7.6 

 7.9 

 8.1 

 8.4 

 8.6 

 8.8 

 9.1 

 9.3 

 9.5 

 9.8 

 10.0 







15 



0.4 

 .5 

 .6 

 .7 

 .7 

 .7 

 ■ .7 

 .7 

 .6 

 .5 

 .5 

 .4 

 .4 

 .4 

 .3 

 .4 

 .3 

 .3 

 .3 

 .3 

 .3 

 .3 

 .3 

 .3 

 .3 

 .3 

 .3 

 .3 



0.08 

 .10 

 .12 

 .14 

 .14 

 .14 

 .14 

 .14 

 .12 

 .10 

 .10 

 .08 

 .08 

 .08 

 .06 

 .08 

 .06 

 .06 

 .06 

 .06 

 .06 

 .06 

 .06 

 .06 

 .06 

 .06 

 .06 

 .06 



0.4 

 .4 

 .5 

 .6 

 .6 

 .7 

 '.7 

 .6 

 .6 

 .5 

 .5 

 .4 

 .3 

 .3 

 .3 

 .3 

 .2 

 .3 

 .3 

 .2 

 .3 

 .2 

 .3 

 .2 

 .2 

 .2 

 .3 

 .2 



0.08 

 .08 

 .10 

 .12 

 .12 

 .14 

 .14 

 .12 

 .12 

 .10 

 .10 

 .08 

 .06 

 .06 

 .06 

 .06 

 .04 

 .06 

 .06 

 .04 

 .06 

 .04 

 .06 

 .04 

 .04 

 .04 

 .06 

 .04 



0.3 



.4 

 .4 

 .4 

 .5 

 .5 

 .5 

 .5 

 .6 

 .5 

 .5 

 .4 

 .3 

 .4 

 .3 

 .3 

 .3 

 .2 

 .3 

 .2 

 .3 

 .2 

 .2 

 .3 

 .2 

 .2 

 .3 

 .2 



0.06 



20 



.08 



25 



.08 



30 



.08 



35 



10 



40 : 



.10 



45 



10 



50 . 



.10 



55 



.12 



60 



.10 



65 . . . 



.10 



70 



75 



.08 

 .06 



80 



.08 



85 



.06 



90 



.06 



95 



.06 



100 •- 



.04 



105 



.06 



110 



.04 



115 



.06 



120 



.04 



125 



.04 



130 



.06 



1.35 



.04 



140 



.04 



145 



.06 



150 



.04 







TiBLE 14. — Number of years required by balsam fir in New York to grow 1 inch. 





Hardwood slope. 

 (Based on 277 trees.) 



Flat. 

 (Based on 246 trees.) 



Swamp. 

 (Based on 158 trees.) 



Diameter breast high (inches). 



Age 

 (years). 



Years 

 required 

 to grow 



1 inch. 



Age 

 (years). 



Years 



required 



to grow 



1 inch. 



Age 



(years). 



Years 



required 



to grow 



1 inch. 



1 



17 

 26 

 33 

 40 

 47 

 55 

 65 

 78 

 93 

 108 

 125 

 142 



17 

 9 

 7 

 7 

 7 

 8 

 10 

 13 

 15 

 15 

 17 

 17 



18 

 28 

 36 

 43 

 51 

 60 

 72 

 89 

 108 

 128 

 150 



18 



10 



8 



7 



8 



9 



12 



17 



19 



20 



22 



20 

 32 

 42 

 52 

 61 

 73 

 89 

 108 

 129 

 150 



20 



2 



12 



3 



10 



4 



10 



5 



9 



6 



12 



7 



16 



8 



19 



9 



21 



10 



21 



11. 





12. . . 















