FOREST COMMISSIONERS REPORT. 



105 



Tabli- 5. — Merchantable volumes of paper birch, by diameter and 

 merchantable length, based on measurements of 396 trees. 



An interesting feature of these tables is the rather high vol- 

 ume shown by paper birch, as compared with many other spe- 

 cies. This is due to the fact that it has a bole which is more 

 or less cylindrical in shape, with a small taper. This is clearly 

 shown in Table 6. The bole is usually straight and free from 

 branches for from 40 to 50 feet from the ground ; above this 

 there are numerous limbs and the taper is quite rapid. Table 

 7 shows the taper of the stump at i-foot intervals from the 

 ground and furnishes a means of determining the breastheight 

 ■diameter of trees of different stump heights. 



