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The method of selection fellings (French jardinage). 



The General plan — The method of selection fellings con- 

 sists in felling here and there, as they are found growing 

 and according to certain cultural rules, such of the exploit- 

 able trees as it is calculated will not exceed the possibility 

 of the forest. Theoretically, every acre of a selection- 

 worked forest should be felled over each year ; but, as the 

 trees felled would be so scattered that it would often not be 

 profitable to remove them, it is usual to fell over a portion 

 of the area each year and thus work over the whole area in 

 a given period at the end of which the portion first worked 

 is again taken in hand. The working.plan thus pre- 

 scribes the number of years in which the whole area is to 

 be worked over ; the area which is to be worked each year, 

 or during a short period of years ; and it limits the quantity 

 of material to be removed, annually or periodically, to the 

 total production over the whole area during the year or 

 period concerned. 



Tins the working-plan might be to the effect that each year there will be felled 

 by the selection metbodi on one-tenth of the area of the forest, such and such a 

 number of trees. 



Limitation of the fellings. — The limitation of the material 

 to be removed may be effected in several ways, viz. : — 



(a) by cultural rules only; 



(6) by prescribing, in addition to cultural rules, the 

 quantity of material or the girth or diameter limits of the 

 trees to be felled ; and 



(c) by prescribing the proportion which the number of 

 trees felled shall bear to the number of stems of certain 

 dimensions in the standing stock. The number of trees 

 or the volume of material which is to be felled may, when 

 precision is required, be calculated by one or another the 

 following methods which will be separately described in 

 the order given : — 



The rate of growth. 

 Enumeration of the trees. 

 Estimation of the production of the soil. 

 The method of relative proportion. 

 The method of proportixjnate volumes. 



