Comment 563 



attainable increment, and that the attainment .of this admittedly 

 can only be accomplished by silviculture. 



The conception of the biology of the forest, according to which 

 apparently every stand experiences regularly a natural deteriora- 

 tion of its producing capacity in early life, which condition can be 

 corrected by fellings, is, to say the least, novel. 



A singular misconception is that of the object of thinnings "to 

 create more favorable conditions of nutrition." This may, under 

 certain conditions, be one of the objects, but the main object is 

 to shift the increment from the large number of components to a 

 select few; to improve the increment in quality. That a tree, a 

 stand, an animal, a man shows in its growth and development 

 the periodicity which gives rise to the growth curve exhibiting 

 rises of rates and declines, is a phenomenon which the best silvi- 

 cvilturist cannot overcome, although to a small extent he may dis- 

 turb the periods to his advantage, as German silviculturists have 

 shown, most beautifully in Wimmenauer's demonstrations of 

 keeping the annual ring width approximately equal for several 

 decades. (See F. Q., vi, p. 432.) 



The charge of arbitrariness in determining the normal stock on 

 the basis of yield tables becomes ludicrous in comparison with 

 the arbitrariness in the determination of his own "rational" stock 

 or etale. The former relies upon measurements of actual, care- 

 fully chosen standards, the conditions of which are known; the 

 latter on nothing but personal opinions. He charges against the 

 normal stock methods what is chargeable against the lack of busi- 

 ness judgment on the part of the manager in applying the method, 

 or what is chargeable to the fluctuations of business in general. 

 The ideal manager who can do what Biolley wishes him to do is, 

 indeed, a rara avis, and the intensity of application which he 

 provides is in large State properties hardly anywhere practicable. 



We may add that the mithode du controle was designed for selec- 

 tion forest and since there is no other satisfactory practical method 

 of organization for this character of forest, this silvicultural 

 prescription may be applied with advantage. For other than 

 selection forest the conception of the normal forest and its use for 

 measiiring silvicultural success on the very ground which Biolley 

 correctly demands — ^maximum increment, quantitative and quali- 

 tative — ^is still useftil and practicable, even to the man who 

 desires freedom from formalism. 



