94 TRANSACTIONS OF ROYAL SCOTTISH ARBORICULTURAL SOCIETY. 
remaining oak trees. The area to be dealt with amounts to 
297 acres, and certainly not less than 15 acres should be taken 
in hand every year, so as to complete the underplanting in not 
more than twenty years. 
The material to be removed may be estimated at one-fifth of 
the existing crop, or 200 cubic feet of timber and two cords of 
cordwood per acre, with about two tons of oak bark. 
(b) Zvreatment of the Second and Third-class Oak- Woods. 
As larger or smaller patches of third-class oak alternate with 
patches of second-class, more particularly in Glenbervie, Willow’s 
Green, and Abbott’s Wood, it is desirable to take these two 
classes together. The area occupied by them should be gone 
over at the rate of a certain number of acres annually, the good 
patches should be treated as described for the first-class oak, the 
inferior patches should be cleared and restocked with conifers. 
The nature of the soil indicates as the most suitable species the 
spruce, which should, therefore, be the principal species to be 
introduced. On the more sandy part, however, Scots, Corsican, 
or Weymouth pines may be planted. In localities sheltered from 
strong wind, a moderate proportion of Douglas fir may be mixed 
with the other conifers. Larch may be introduced as a sprinkling 
not exceeding 10 per cent. of the crop; a larger mixture is 
undesirable, owing to the liability of the tree to become 
diseased. In damp hollows, patches of ash may be introduced. 
It is, of course, desirable that the operations should be com- 
menced in those woods which contain the largest proportion of 
third-class oak. These are—Glenbervie, Willow’s Green, and, 
next to these, Abbott’s Wood. 
As the future crop in these woods will, to a considerable 
extent, consist of conifers, certain precautions have to be taken. 
The cutting and conversion must be arranged in such a manner 
that the age-classes are hereafter properly located, that is to 
say, the older of any two woods must lie on the lee side of the 
prevailing wind, which, in this case, is the west, south-west, or 
north-west wind. Another point is that arrangements must be 
made to avoid a multiplication of injurious insects, more 
especially of the bark beetles. These two objects will be 
realised by the following two measures :— 
1. By commencing cutting on the east and proceeding 
gradually towards the west. 
