4 DWAKF-TREES [CH. 



Hazels of any copse, or the Willows of any osier-bed where, 

 the main stems having been cut down close to the ground, 

 numerous basal branches of approximately equal strength 

 arise, and the whole assumes the shrubby form of Coppice. 

 Similarly with the close-cut hedges of Hornbeam, Beech, 

 Yew, &c., met with in many parts of the country. A 

 striking example of the effects of continued pruning by 

 animals is that of the Scots Firs described by Darwin 1 : 

 I quote the case in extenso, since it is very instructive 

 on several points. " In Staffordshire, on the estate of a 

 relation, where I had ample means of investigation, there 

 was a large and extremely barren heath, which had never 

 been touched by the hand of man ; but several hundred 

 acres of exactly the same nature had been enclosed 25 years 

 previously and planted with Scotch fir. The change in 

 the native vegetation of the planted part of the heath 

 was most remarkable, more than is generally seen in 

 passing from one quite different soil to another : not only 

 the proportional numbers of the heath-plants were wholly 

 changed, but twelve species of plants (not counting grasses 

 and carices) flourished in the plantations, which could not 

 be found on the heath. The effect on the insects must 

 have been still greater, for six insectivorous birds were 

 very common in the plantations, which were not to be 

 seen on the heath ; and the heath was frequented by two 

 or three insectivorous birds. Here we see how potent has 

 been the effect of the introduction of a single tree, nothing 

 whatever else having been done, with the exception of the 

 land having been enclosed, so that cattle could not enter. 

 But how important an element enclosure is, I plainly saw 

 near Farnham, in Surrey. Here there are extensive heaths, 

 with a few clumps of old Scotch firs on the distant hill-tops : 

 within the last ten years large spaces have been enclosed, 

 1 Origin of Species, 6th ed. 1885, p. 55. 



