SfitiECTIdN-WOEKED PORligTS UNDBE TEANgSOEMATiON. 1^1 



in which reproduction and even simple growth may be possible only 

 under great difficulties. The constant preservation of the leaf- 

 canopy is here a more important condition than the transformation 

 Or regulariaation of the forest. Such portions constitute the natural 

 protection for those situated below them, and the maintenance 

 therein of the Selection System is necessary for their own existence, 

 'I'hey may ordinarily be recognised from the portions capable of 

 transformation by certain distinctive characters ; for instance, the 

 beech or the spruce may there be more numerous than elsewhere 

 or the trees there may be dwarfed and misshapen, or the leaf-canopy 

 may be incomplete in places or vary in density from point to point • 

 or, lastly, special and diverse phenomena observable may point out 

 the particular portion or belt which must be continued to be worked 

 on the Selection System. 



The requisite separation just described being effected, the rest 

 of the forest should then be divided off into Working Circles accord- 

 ing to the general rules regulating that operation. And, as in forests 

 treated by Selection, trees of all ages are found mixed up together 

 without any order whatsoever, the main point to bear always in 

 mind is the grouping into one and the same Working Circle of only 

 such portions of the forest as require all the same Rotation. 



The length of the Rotation to adopt must, of course, depend on 

 the diameter the trees must attain in order to yield what is in 

 greatest demand in the market and is the most useful to the country 

 at large. In our finest silver fir forests of the Aude and the Jura, 

 it is only when the trees have acquired a diameter of 28 inches at 

 th« height of a man from the ground, that they are classed as large 

 timber and possess for every cubic foot of their volume the highest 

 money-value and the largest sum of utility they can ever attain. 

 In such forests the problem to solve is at what age the silver fir 

 grown in Regular High Forest will attain this diameter. The trees 

 of a forest worked by Selection reach this size at very different ages, 

 according as they have been overtopped for a longer or shorter time, 

 have maintained themselves in a more or less vigorous condition, 

 and possess more or less healthy and well-furnished crowns. But 

 amongst these trees there must always be some that have grown up 

 as if they had been reared in a regular high forest; they may be 



