242 THE WORKING SCHEME IN COMPOUND COPSES. 



of the trunk then becomes blackish and covered with cryptogamic 

 plants, as also the extreme short and irregular branches. The 

 general appearance of the crown is then one of languishing vegeta- 

 tion. Where the oaks are wanting, the ash should be reserved with- 

 out any limit as to number, provided that the trees thus preserved 

 stand well apart. 



The aspen enjoys here a longevity which varies greatly between 

 80 and 90 years. It remains sound only as long as it is growing 

 rapidly ; and while in this state, its bark retains its lustrous appear- 

 ance on the upper portion of the bole, and its crown is perfectly full 

 and well furnished with branches on every side. It is mature, when 

 dead bark covers the whole length of the bole, and the extremities 

 of the branches begin to wither and dry up. Once it has reached 

 this stage, it decays in a very few years. In the absence of any 

 better species, the aspen may with advantage be reserved, but, as a 

 rule, for two Rotations only. 



The birch, which grows less rapidly, possesses on the whole great- 

 er longevity. It flourishes up to the age of 60 years at least, and 

 in most cases up to 100 years, provided, above all things, it stands 

 completely isolated. Trees which possess a broad and thick foot are 

 the most vigorous. There is no advantage in preserving birch, once 

 the crown has lost some of its branches and the branchlets begin 

 to die. This is a sign that the tree is mature. The birch, useful 

 as a standard scattered about here and there and up to the end 

 of the fourth Rotation at the outside, ought not to be numerous 

 enough to form a sort of leaf-oanopy, which keeps down the under- 

 wood and does serious injury to the oak. 



The beech has its use chiefly in those portions of the forest, 

 which are elevated and stocked with birch, where no other species 

 could protect the soil and yield a full underwood. Individuals of this 

 species may, as a rule, be reserved up to the category of 3rd. class 

 standards in order to se.ve as prolific seedbearers. Those which 

 are of tall habit do least damage to the undergrowth. Beech stand- 

 ards should, as far as possible, be well distributed amongst more 

 numerous standards of the valuable species, and they should, with 

 rare exceptions, be felled at the end of their third Rotation, their 

 place being taken by younger individuals of the same species. 



