16 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



are always the most stunted and least bulky in the trunk. 

 Looked at in the mass the tops of the trees rise up in a gently 

 rounded slope from the exposed side to the sheltered side, and 

 when you come to examine the trees critically the difference is 

 only the more apparent. Here are examples of the relative 

 .dimensions of trees growing in an exposed narrow belt about 

 750 feet above the sea, consisting of Beech, Sycamore, Oak, Elm, 

 Chestnut, and Larch : — 



Table showing the Effects of Exposure and Shelter on the Growth of 

 Forest Trees in Mill- Moor Plantation Belt on the Wortley Estate. 



Kind 



Height of trees on 

 the most exposed side 

 of belt 



Height of trees in the 

 middle of belt where 

 less exposed 



Height of trees on the 



inner and most 

 sheltered side of belt 



Beech 



31 feet 



37 feet 



43 feet 



Sycamore 



28 „ 



36 „ 



45 „ 



Ash 



26 „ 



35 „ 



44 „ 



Oak 



21 „ 



36 „ 



40 „ 



The bulk of timber is in proportion to the height. Age of plantation 

 about 60 years. 



The trees in this plantation are growing under precisely the 

 same conditions, except only as regards exposure, and the table 

 will show at a glance the immense difference that that would 

 make in an acre as regards the quantity of timber obtained 

 and its value. The practical conclusions to be drawn from 

 data of this kind are that in deciding to plant poor land the 

 warmest and least exposed situations should be chosen first, and 

 these, in high-lying, hilly districts, are the situations that face 

 south, west, or east, or any point between these, and the lower 

 slopes of hills in preference to their tops. The tallest trees and 

 greatest bulk of timber are produced much sooner at the bottom 

 of the hill than higher up. The late Mr. John MacGregor, 

 forester to the Duke of Atholl, told me (and also stated in his 

 evidence before the Select Committee on Forestry) that his 

 plantations of Larch in a certain wood were worth " perhaps 

 nearly ^100 " per acre at the bottom of the hill, and higher up, 

 at an altitude of 1,000 feet, " not worth more than £20 per acre " 

 — a vast difference, due mainly to altitude and exposure. In 

 Wharncliffe Wood, which runs for about four miles along the 

 valley of the Don, ascending regularly its whole length to the 

 top of Wharncliffe Crags, the same decrease in value is plainly 



