36 BULLETIN 820, U, S, DEPAETMEWT OF AGKICULTURE. 



Table 19. — Double bark thickness, at diameter breast high, of jack pine in Minnesota, 



Diameter 

 breast 



Hubbard County, Minn. 



Cass Covmty, Minn. 



Trees in dense 

 stand. 



"Iso- 

 lated" or 

 partly 









high. 





"iso- 

 lated" 



Basis. 



Bark. 



Basis. 









Bark. 



Basis. 



trees. 

 Bark. 









Inches. 



Inches. 



Trees. 



Inches. 



Trees. 



Inches. 



Trees. 



2 

 3 

 4 

 5 

 6 

 7 



0.23 

 .30 

 .38 

 .46 

 .54 

 .63 



15 

 28 

 66 

 75 

 80 

 85 























0.39 

 .43 



.47 

 .52 





6.49 

 .61 



,72 



3 



8 

 9 







i 



8 



.72 



57 



.84 



13 



.56 



4 



9 



.82 



47 



.94 



7 



.61 



8 



10 



.92 



43 



1.05 



5 



.07 



16 



11 



1.03 



22 



1.15 



7 



.73 



7 



12 



1.14 



13 



1.25 



4 



.80 ■ 



10 



13 



1.26 



6 



1.34 



1 



.87 



3 



14 



1.37 



6 



1.43 



1 



.94 



1 



15 

 16 



1.48 

 1.59 



1 

 2 



1.51 

 1.59 





1.02 

 1.09 



1 

 1 



2 



17 

 18 

 19 

 20 



1.70 

 1.79 



1.87 

 1.94 



3 







1.17 

 1.25 

 1.33 

 1.41 



































549 



CO 



52- 



Table 20. — Average thickness of bark at different heights above the ground in •predominant 

 ' jack pine trees in Hubbard County, Minn. 



[Trees 22 to 102 years old. Measurements by H. H. Chapman, 1905.] 



Diam- 







Height above ground (feet). 









eter 

 breast 













Basis. 



















high. 



1 



9 



17 



25 



33 



41 



49 



57 





Inches. 



















Trees. 



5 

 6 

 7 

 8 

 9 

 10 



0.60 

 .64 

 .70 

 .76 

 .83 

 .91 



0.18 

 .23 

 .26 

 .29 

 .32 

 .35 



0.12 

 .17 

 .19 

 .21 

 .23 

 .26 



0.10 

 .12 

 .14 

 .16 

 .18 

 .21 











2 

 8 

 15 

 16 

 33 

 37 



0.08 

 .10 

 .12 

 .15 

 .17 









0.06 

 .09 



.12 

 .14 















0.09 





11 



.96 



.38 



.28 



.23 



.18 



.15 



.10 





21 



12 



1.01 



.41 



.31 



.25 



.20 



.17 



.11 





12 



13 



1.05 



.44 



.34 



.27 



.22 



.18 



.12 





9 



14 



1.09 



.47 



.37 



.29 



.23 



.20 



.14 



0.11 



3 



15 



1.12 



.50 



.39 



,31 



.25 



.22 



.17 



.14 



1 



16 



1.14 



.52 



.41 



.33 



.27 



.24 



.20 



.17 



2 



17 



1.16 



.54 



.43 



.35 



.29 



.26 



.23 



.20 



3 



162 



