FOREST ECONOMY. 205 



during which the difference in stock is to be 

 equalized and the normal stock is to be secured 

 either by saving of increment, if there be a de- 

 ficiency, or by removing any surplus during the 

 period of equalization ; the establishment of the 

 proper series of age classes being left to the future. 

 The felling budget (b) which will secure this 

 equalization may be expressed by formula : 



b=I Sa ~ Sn 

 e 



The choice of the period of equalization (e) is to 

 be made with due consideration of the financial 

 aspects of the property and the owner's financial 

 capacity. 



Altogether, the principle of the " owner's inter- 

 est" must be the guiding one in the management 

 of any property ; and it would first have to be dem- 

 onstrated that a sustained yield management, either 

 annual or intermittent, and sacrifices of revenue in 

 the present for the sake of a future improved 

 revenue are in his interest. For it must always be 

 remembered that financially forestry means forego- 

 ing present revenue or incurring present expenditure 

 for the sake of future revenue ; it involves gauging' 

 present and future advantages, and the time ele- 

 ment, as we have seen, is the prominent element 

 in its finance calculations. 



Before an annual sustained yield management 

 will appear profitable in the United States, many 



