SYLVICULTURE 57 



the overhead or surrounding cover to become denser, or such 

 clumps of " advance growth " can be used as centres for 

 larger groups. Opportunity is sometimes taken of utilising 

 small clearings in a pure wood to introduce other species 

 either by sowing or planting, and thus to convert it gradually 

 into mixed forest, wherein the new species have the advan- 

 tage of a start. With these groups as nuclei, regeneration 

 proceeds in widening circles, until, after a while, the connecting 

 wood comes under treatment. 



In the case of regeneration occurring over a whole wood or 

 compartment (" Compartment System of Natural Regenera- 

 tion under a Shelter Wood "), the process generally extends 

 over a long number of years, and the method of stocking the 

 ground bears a resemblance to that followed in the " Selection 

 System." The forest is divided into a number of sections, 

 among which the fellings are undertaken at short intervals 

 (five to ten years). At each felling the largest trees, and any 

 that are badly misshapen, damaged, or diseased, are removed. 

 Attention is paid to the requirements of the young plants for 

 light, and the needs as regards thinning, etc. of trees of 

 all ages. In this way there are represented upon the area at 

 the same time nearly all stages of forest growth. 



Natural Regeneration by Coppice Shoots 



Broad-leaved trees have the power, varying in the different 

 species, of reproducing themselves through the production of 

 coppice shoots. These latter spring from the stool and 

 roots after the trees have been felled close to the ground. 

 Areas restocked by this means are called Coppice woods. 



Certain trees (Willows, Poplars) may be cut over at some 

 distance from the ground, and shoots allowed to grow from 

 the stems and cut surfaces. Pollarding is a well-known 

 form of this, but is without importance sylviculturally. 



The faculty of throwing up stool shoots of sufficient 

 vigour to be useful can be artificially assisted by paying 

 attention to a few matters. It is of importance that the 



