CHOICE OF SYSTEMS 31 



On the other hand, as the groups are enlarged, so will 

 the protection from wind be lessened. 



The total quantity of timber produced under the group 

 and the selection systems, does not vary materially from that 

 produced under even-aged high forest. 



As these two systems depend upon natural regeneration, 

 though artificial aid may be given, it is imperative that 

 rabbits be exterminated, or the whole areas will have to be 

 wired in. 



