CLIMATE AND TREE GROWTH 101 



leaves of deciduous trees in summer, red and brown in a 

 few hours. The Scots pine, larch, and spruce are parti- 

 cularly liable to this injury, and probably few but the 

 more tj^pical maritime trees are exempt from it. 



Taking the British Isles by themselves, the wind in- 

 fluence is aggravated by the fact that they stand out in 

 the Atlantic sufficiently far to derive the special benefit 

 or disadvantage, according to the point of view from 

 which they are studied, from Atlantic gales. Probably 

 this would be evident still more clearly if it Avere not that 

 the greater part of the coast-line of Scotland, Wales, and 

 Ireland is occupied by mountain chains which tend to 

 break the full force of the wind in many districts. The 

 more broken the ground the more frequently will severely 

 exposed and exceptionally sheltered spots alternate, 

 and the fact that trees frequently do well in the latter 

 is brought into greater prominence than the equally 

 obvious fact that the growth on the former is slow, 

 stunted, and unprofitable. 



Trees grown in thick masses on comparatively level 

 ground suffer least from winds of an ordinary character, 

 and when it is possible to obtain land of this character 

 the adverse components of British climate, so far as wind 

 is concerned, may be practically counteracted. But in 

 most districts, especially those on the western side of the 

 British Isles, flat land is not a common feature, and what 

 there is of it cannot be given up to tree-growing. This 

 side of England and Wales, Scotland and Ireland certainly 

 has its advantages, for it provides a number of sheltered 

 valleys and slopes which, if use is made of them, enable 

 trees to be grown to a satisfactory size, and at a fairly 

 rapid rate, within a few miles of the coast-line. The 

 humid atmosphere of such districts again is particularly 

 favourable to many species of conifers, especially those 

 from the Pacific slopes of North America, like Douglas fir. 



