24 FOREST SYSTEMS 



between the felling of one group and its neighbour ; by this 

 means only a small area is laid bare at a time, and the young 

 trees are protected from wind and sun by the other trees 

 adjoining. The regeneration is almost always brought about 

 by natural agencies, and takes place from seed shed from the 

 neighbouring trees. If the groups are large, it is advisable 

 to leave a few trees on any group that is being felled, so as to 

 insure a more even seeding. 



When dealing with any area under this system the usual 

 plan is to endeavour to bring about the complete regenera- 

 tion of the whole area in a period of from 30 to 45 years, 

 after which it will be some 50 to 60 years, according to the 

 length of the rotation, before the timber on the original 

 group will be ready for the axe. 



It is a system that is only suitable to shade-enduring 

 trees, which are fairly storm-proof. On the Continent, Silver 

 Fir is often regenerated in this way, but the possibility of 

 regenerating Silver Fir naturally in this country, seems to be 

 confined to a few localities. 



The method should give good results with Douglas Fir or 

 Sitka Spruce or Thuya gigantea. 



3. The Compartment System. 



This system of high forest is capable of many variations, 

 and will be considered under the subdivisions as already 

 indicated. But there is a broad distinction between this 

 system, including all its variations, and the two former 

 systems described, which is evidenced by the fact that under 

 the compartment system, fellings and regenerations are refer- 

 able to compartments or large blocks of land of 5, 10, 20, or 

 even 50 acres in extent ; whereas under the group system 

 fellings and regenerations take place only on small groups or 

 patches at a time, and under the selection system the opera- 

 tions are still more sporadic. 



These compartments are preferably made rectangular in 

 shape, with sides in the proportion of 3 : 2. The long side 

 should always be at right angles to the direction of the pre- 

 vailing winds, for by this means the danger from windfall in 



