Canadian Forest rij Journal, December, 191, 



1439 



Fast-Growing White Spruce in Quebec 



Dcnwnslidling the Possibililij of Producing 

 Piilpwood in 30 Years. 



(a) Ordinary Growth. 



(b) Fast Growth. 



A piece of ordinary growth white spruce showing almost fourteen annual rings, compared 



with a piece the same size of rapid growth white spruce from Quebec, showing a 



little more than two annual rings. Both pieces are magnified two diameters. 



A sample of wood recently sub- 

 mitted to the Forest Products Labora- 

 tories, Montreal, shows- what may 

 be expected of white spruce when it 

 Is growing in a favorable position. 

 The tree from which the sample was 

 taken was 29 years old and was 12 

 inches in diameter at \8 inches from 

 the ground, which means that the 

 tree averaged to add almost seven- 

 sixteenths of an inch to its diameter 

 every year of its life. It is interest- 

 ing to know the effect of such rapid 

 growth on the properties of the wood 

 and the following gives the results 

 of certain determinations together 

 with comparisons with wood cf a 

 more usual, slower growth. 



The absolutely dry specific gravity 

 is 0.354, which indicates 22.1 pounds 

 per cubic foot. According to recent 

 reports of the U.S. Forest Service, 



based on determinations of many 

 samples, the average weight per cubic 

 foot of white spruce, absolutely dry, 

 is about 27 pounds. It appears, 

 therefore, that this rapidly grown 

 specimen is about 20 per cent, less in 

 weight per cubic foot than the aver- 

 age white spruce. 



Since spruce is the most valuable 

 wood in Canada for sulphite pulp 

 an examination of the length of fibre 

 was made. This showed that in the 

 last year of growth, i.e., 29 ^'-ears 

 from the pith, the fibre averages 3.45 

 millimeters in length, and at 19 years 

 from the pith it averages 2.72 milli- 

 meters in length. It may here be 

 stated that the fibre ordinarily is 

 longer in each successive year's 

 growth until about 50 annual rings 

 have been formed. Furthermore, at 

 any given number of years from the 



