528 



APPENDIX 



RESULTS OF BORINGS WITH PRESSLER'S INCREMENT BORER 

 Number of years to pass from one diameter class to another 



The 35 trees take in the aggregate 539 years to pass from one diameter class to an- 



539 

 other or an average of -^ = 15.4; that is to say in 16 years aU the stems should pass 

 oo 



through one diameter class (2 inches); the length of the cutting period is therefore 



justified. The curve given below brings out this point even clearer: 



10 



14 



16 18 20 22 24 



Diameter Breast High in Inches 



28 



30 



32 



