570 Forestry Quarterly. 



regulations as to cutting, etc., will not apply to the areas held 

 under Crown grants, nor to the E. & N. Timber belt, which to- 

 gether amount to 1,200 thousand acres. There may also be a cer- 

 tain percentage of Crown timber held under license and unrenew- 

 able lease, which when logged-off will be found to be fit for agri- 

 cultural settlement. To this it may be answered that, to offset 

 these areas, there is an unknown number of millions of acres 

 (but probably not fewer than five) upon which the stand is at 

 present either immature, inaccessible by available methods, its 

 yield below eight thousand feet to the acre, or the quality poor, 

 which has now no commercial value and is therefore still the 

 property of the Crown, 



Furthermore, an attempt must be made to find answers to the 

 three following questions : 



(i) What will be the duration of the visible supply of timber? 



(2) What will be the possible constant annual yield per acre? 



(3) What will be the probable legitimate period of rotation? 

 (i) Until 1910 the scaled output of our forests was under 



700 million feet per annum, or less than 50 feet per acre. A 

 reasonably liberal figure must be assumed for the probable in- 

 crease of the demand which governs the supply. The annual in- 

 crease in lumber consumption has been spasmodic rather than 

 constant. Between 1888 and 1892 the output doubled; remained 

 stationary till 1894; doubled in 1898, 1902 and 1905, and in- 

 creased nearly 40% in 1909, when the production reached 607 

 million feet. If the demand were to keep on increasing 10% 

 each year the available supply would be exhausted in sixty years,^ 

 even at Fernow's estimate of 300 billion feet. If, however, an 

 increase of only 5% be conjectured, the time-limit of exhaustion 

 of the present stand would extend to 120 years. 



During the century from 1807 to 1907 the output of lumber 

 in the United States increased from perhaps 100 million to 35 

 billion feet, representing a cumulative annual increase of about 

 8%. The anology is far from perfect, owing to altered condi- 

 tions, and especially to the introduction of steam. But he would 

 be bold indeed who would assume that the present crop of our 

 British Columbia forest would last more than 100 years. 



(2) Unfortunately, in speculating upon a possible sustained 

 annual yield per acre, we have no data gathered from our own 

 forests bearing upon the subject, and therefore it will be neces- 



