Forestry Quarterly. 



Taper. — The taper of Jack Pine is not at all excessive. Exces- 

 sive taper is always an indication of poor soil and difificult condi- 

 tions of growth, while the full-boled tree is found only on deep 

 loamy soil with optimum silvical surroundings. Other things 

 being equal the taper is greater and more variable from the 

 ground to diameter breast high, and in the top. For the mer- 

 chantable portion of the tree for a length of 8 feet, the taper 

 varies from .6 inches to 1.4 inches, with an average of i inch; 

 (like most other Canadian species) while in the crown and butt it 

 is much greater and ranges from i inch to 3 inches per unit length 

 of 8 feet. 



TABLE No. 3. 



Taper of Logs. 



Basis 79 trees 

 Diameter 

 breast-high. Diameter inside bark at given height above ground. 

 Outside bark 



Inches 9 ft. J? ft 25 ft. 33 ft. 41ft. 49 ft. 57 ft. 66 ft. 73 ft. 



5 

 6 



7 

 8 

 9 

 10 

 II 

 12 

 13 

 14 

 15 

 16 



4-9 

 5-9 

 6.5 



7.5 

 8.6 



9-5 

 10.2 

 10.9 

 II. 7 

 12.2 

 13.0 

 137 



3.6 

 4.8 

 5-2 

 6.5 



7.8 

 8.2 



9-5 

 10. o 



II. o 



II-3 

 II. 8 

 12.8 



1.6 



3-3 



4-1 



5-7 



6.9 



7-5 



8.7 



8.9 



10. 1 



10.6 



II .2 



II .2 



1-7 

 2. 1 



4-7 

 6.1 

 6.6 

 7.8 

 8.1 

 9.1 



9-5 

 10.2 

 10.7 



2.4 

 30 

 4-1 

 4.8 

 5.8 

 7.0 

 7.4 

 8.0 

 8.4 



• 7 

 1-5 

 2.5 

 30 

 3.6 

 S-i 

 5-7 

 6.0 

 6.4 



Bark. — Jack Pine has a thin bark which is fissured into irregu- 

 lar confluent rounded edges, with close scales of reddish color. 

 It increases in thickness from that of fifteen inches on the sapling 

 to that of six inches on the mature tree standing in the open. 



The perceniage of bark as compared to that of the total volume 

 of the tree varies but little. The average on 100 trees being 

 found to be 11%. It might be expected that as the volume of the 

 tree increases the bark percentage should decrease, but there is 

 not more than 1% difference in the percentage amount on a 5' 

 tree as compared with a 15" tree. 



