52 WIND AND TREE-FORM [CH. 



the prevailing blasts. The trees or bushes are all stunted 

 and smoothed off, as it were, on the windward side, and 

 more or less drawn out or hanging over towards the 

 sheltered side, and the opinion is very popular that the 

 force of the wind has blown-over the shoots so that 

 they come to lie in the direction in which they mainly 

 point. 



s, 



y- 



A B C 



Fig. 13. Diagrams to show the effect of wind on tree-form. 



But this is not the explanation of the fundamental 

 phenomenon at all. Let us suppose the diagram A in 

 Fig. 13 to be a tree henceforth exposed to prevailing 

 high winds from the west. In course of time the twigs 

 and branches facing the west are found to be much more 

 stunted than those on the sheltered side towards the 

 east, as seen in B, because the drying action of these 

 prevalent high winds has killed many of the buds by 

 over transpiration, and each bud killed means so much 

 shoot-system the less. On the sheltered side, however, 

 there has been less destruction of buds and a corre- 

 sponding outgrowth of longer shoots, with more suc- 

 cessful buds, developing again to longer shoots more 

 richly supplied with buds, until at length the state of 

 affairs diagram matically represented in C is attained, 

 where the extensive growth towards the east is more 

 and more pronounced according to the sheltering influ- 



