SOME PRACTICAL SUGGESTIONS. 25 



the seaboard. But latitude or distance from the sea does 

 not wholly determine the altitude at which trees may be 

 grown. For example, trees are grown successfully to 

 greater altitudes in middle and eastern Inverness-shire 

 than in the south-western counties of Scotland, showing 

 that other influences must be taken into account. In the 

 treatment of new ground it will be a wiser and more 

 profitable policy to keep within the absolute limit of 

 altitude than to exceed it, and in determining what this 

 point is, aspect and shelter, and soil quality, frequently 

 have a greater influence than latitude or distance from 

 the sea. 



The effect of aspect and shelter has an important bearing 

 on the ultimate success of tree-growth. This is especially 

 so in proximity to the seaboard. In all cases their effect 

 is determined by the proximity or absence of land that is 

 considerably higher than the planting limit. As a general 

 rule, slopes facing south and west that is, facing the 

 prevailing winds have a lower planting-line than those 

 facing north that is, on the sheltered side of the hills. 

 But shelter is provided not only by higher ground to wind- 

 ward. Even on an exposed slope trees will grow better 

 and straighter, and be less liable to be blown down, and 

 the altitude for tree-growth will be increased, if in the 

 immediate background of the slope there is ground of a 

 considerable height above the limit of tree-growth. It 

 has been observed that such high ground, provided it be 

 in the immediate background, serves to lift the wind and 

 break its force upon the trees. In all cases, and particularly 

 in mountainous regions, the effect of shelter on the progress 

 and stability of trees in general, and also on the quality 

 of timber, must be carefully taken into account, because 

 the shelter afforded by the high tops may not infrequently 

 discount to a great extent the effect of latitude or proximity 

 to the seaboard. 



Soil quality is, under all conditions, of primary import- 



