Balsam fie. 



37 



As shovm by the tables, the best growth is made on hardwood 

 slope; the poorest in swamps. 



Table 15 shows the diameter growth of balsam fir in Maine for all 

 types. The average growth here equals the best growth in the 

 Adirondacks. On the whole, however, the periods of most rapid and 

 slowest growth coincide. 



Table 15. — Diameter growth of balsam fir in Maine, on the basis of age. {All types, 



based on 456 trees.) 



Age (years). 



Diameter 

 breast 

 high. 



Growth 

 in diam- 

 eter 

 every 

 5 years. 



Annual 

 growth 

 in diam- 

 eter 

 within 

 5-year 

 period. 



Age (years). 



Diameter 

 breast 

 high. 



Growth 

 in diam- 

 eter 

 every 

 5 years. 



Annual 

 growth 

 in diam- 

 eter 

 within 

 5-year 

 period. 



15 



Inches. 

 0.4 

 1.2 

 2.0 

 2.7 

 3.4 

 4.1 

 4.8 

 5.5 

 6.1 

 6.7 

 7.3 

 7.9 

 8.4 

 8.9 



Inches. 



Inches. 



85 



Inches. 

 9.4 

 9.9 

 10.4 

 10.7 

 11.0 

 11.3 

 11.6 

 11.9 

 12.1 

 12.3 

 12.5 

 12.6 

 12.8 

 12.9 



Inches. 

 0.5 

 .5 

 .5 

 .3 

 .3 

 .3 

 _ .3 

 .3 

 .2 

 .2 

 .2 

 .1 

 .2 

 .1 



Inches. 

 0.10 



20.. 



0.8 



.8 

 .7 

 .7 

 .7 

 .7 

 .7 

 .6 

 .6 

 .6 

 .6 

 .5 

 .5 



0.16 

 .16 

 .14 

 .14 

 .14 

 .14 

 .14 

 .12 

 .12 

 .12 

 .12 

 .10 

 .10 



90 



.10 



25 



95 



.10 



30 



100 



.06 



35.. 



105 



.06 



40 



110 



.06 



45 



115 



.06 



50.. 



120. 



06 



55.. ■ . 



125... . 



04 



60... 



130 



.04 



65 



135 



.04 



70 



140 



.02 



75.. 



145. 



04 



80 



150 



.02 









SUMMARY. 



Diameter breast high (inches). 



Age 

 (years). 



Years 



required 



to grow 



1 inch. 



Diameter breast high (inches). 



Age 

 (years). 



Years 



required 



to grow 



1 inch. 



1 



19 

 25 

 32 

 39 

 47 

 54 

 62 



19 

 6 



7 

 7 

 8 

 7 

 8 



8 



71 

 81 

 91 

 105 

 123 

 152 



9 



2 



9 



10 



3 



10 



10 



4 



11 



14 



5 



12 



18 



6 



13. 



29 



7 











EFFECT OF OPENING UP FOREST UPON DIAMETER GROWTH. 



That the diameter growth of balsam fir is stimulated by opening 

 up the forest is indicated by measurements of trees growing on 

 uncut and on culled land (Table 16). 



Table 16. — Diameter growth of balsam fir, Grafton County, N. II., on uncut and culled 



land. 



Present diameter breast high 

 (inches). 



Diameter, in inches, 

 breast high after 

 10 years. 



Present diameter breast high 

 (inches). 



Diameter, in inches, 

 breast high after 

 10 years. 



Uncut 

 land. 



Culled 

 land. 



Uncut 

 land. 



Culled 

 land. 



6 



6.54 



6.80 

 7.80 

 9.56 

 10.60 



10 



11.18 

 11.88 

 12.88 



11.40 



7 



11 ... 



12.34 



8 



9.26 

 10.20 



12 



13.34 



9 



13 



14.34 











