126 BRITISH FOREST TREES 



canopy along with the pine, so that the whole attains maturity 

 as a mixed crop. In such cases indifferent stems of pine 

 should of course be removed in favour of the younger silver fir. 



Mixed forests of silver fir and beech are of considerable 

 sylvicultural and economic value on suitable situations, but 

 as the latter almost always forms the ruling species, the nearer 

 consideration of such woods will be more convenient later 

 on (vide pages 175, 176). 



In demands as to soil and situation, the oak resembles the 

 silver fir much more than it does the spruce, so that an 

 admixture of oak, in forests where silver fir is the principa 

 species, is by no means out of accordance with the teachings 

 of nature, though such a mixture is more successful when 

 the beech also finds a place in the woods. When oak and 

 silver fir are to form a crop of nearly the same age, an 

 advantage must be won for the oak by the use of good stout 

 transplants, and by putting them out as early as possible. 

 Even then, however, it is of little use to plant singly, or in 

 rows, or small patches, as the oak is almost bound to be 

 sooner or later overtaken and suppressed by the more rapidly 

 growing silver fir. Experience has shown that it is best to 

 introduce the oak in large groups, which are able to form 

 canopy for themselves and to throw sufficient shade on the 

 ground to hinder the silver fir somewhat in normal develop- 

 ment ; later on, when the oak begins to have an interrupted 

 canopy, the weaker stems can be thinned out so as to permit 

 of the silver fir enjoying a greater measure of light and air, 

 and in the later stages of growth the oak will usually be found 

 to require some protection against the ruling species. Long 

 before reaching maturity, such groups are considerably 

 reduced below their original area, for the silver firs growing 

 round the edges usually succeed, despite ordinary operations 

 of tending, in overtopping and suppressing the oaks along 

 the fringe of the groups. As a matter of fact, such mixed 



