10 Some Problems of Re-ajfore station. 



must be retained till the end of the rotation, whereas if 1,000 

 oaks had been planted in the first instance 800 inferior 

 individuals would have been removed in the course of the 

 rotation, and the 200 retained till the end would certainly 

 comprise larger and finer stems. This argument would 

 necessarily be greatly strengthened if the wood were planted 

 pure in the first instance, containing, as it would do, three or 

 four thousand plants ; and still more so if it had been estab- 

 lished by artificial sowing or by natural, regeneration, when 

 perhaps there might have been fifty to a hundred thousand 

 seedlings from which to make the selection of 200 as the 

 main crop. One has only to examine a pure wood of any 

 species to realise how great is the difference in individual 

 characteristics. Broadly speaking, the greater the numbers 

 the greater is the .opportunity for selecting high-class stems 

 to form the final crop. 



While it is desirable to emphasise the importance of this 

 consideration it is not necessary to push the idea to the extent 

 that one finds in some countries. Thus in some forests in 

 Denmark beeches are planted not as single trees but in bunches 

 of five to fifteen, so that instead of having three or four 

 thousand from which to select, one has five to fifteen times 

 that number. 1 But if this extreme is bad the other, which 

 allows little if any opportunity for selection, is worse. 



While the Douglas fir and spruces are generally best grown 

 in pure woods, or, at least in pure groups, there are often 

 advantages in growing such trees as the oak and larch in 

 association with beech. If the land is of a good class for oak 

 this tree will grow well alone, but if the soil is thin, rather 

 light, and dry, much better growth of the oak will be secured 

 by a mixture with beech. Very fine oaks are to be found 

 thinly scattered in beech woods on the Chilterns, Cotswolds, 

 and other limestone areas. Similarly as regards larch, which 

 often reaches its largest dimensions on quite shallow soil if 

 nourished by beech humus. But larch is such a profitable 

 crop, even when of quite moderate dimensions, that, as a rule, 

 it may be planted pure. In making this suggestion it is not 

 forgotten that the common larch is sometimes severely attacked 

 by disease, but it is rare that at the age of twenty to thirty 

 years more than 50 per cent, of the stems are attacked, and 

 infection after that age is unusual, and in no case serious. It 

 is on this fact that the Novar system of combating larch disease 

 is based. On Sir Ronald Munro-Ferguson's estate of Novar, in 

 Easter Ross, the larch is planted alone, and at the age of sixteen 

 to twenty years all diseased and inferior stems are removed, 



1 Quart. Journ. For., Vol. iii., p. 79. 



