158 Proceedings of the Royal Physical Society. 
the more elaborate L and T notching, is penny wise and pound foolish 
wherever there is reason to suspect the presence of Hylastes in the 
neighbourhood. Ball- or pit-planting in such conditions is true economy. 
Special measures are more likely to be necessary against H. ater and 
Hi. cunicularius than against H. palliatus. Unfortunately they are difficult 
to devise and costly to carry out. Uprooting of stumps is undoubtedly 
the most effective special measure. I have repeatedly observed that the 
roots of wind-blown trees are never attacked by the root-feeding Hylastes, 
or if attacked before being blown are deserted after uprooting. Such a 
method is unfortunately costly, and leaves the felled area littered with stumps 
which have to be got rid of. They possess almost no market value and are 
heavy and awkward to remove. Burning them is as costly as removing them, 
and it is doubtful whether uprooting of stumps will ever be generally adopted 
for these reasons. Another method is the burning of brushwood and other 
litter on the tops of the stumps. I have already referred to it, and have 
doubts as to its value. It is also costly, ranging from 30s. to £2 per acre. 
Creosoting of the stumps is yet another method. I have, unfortunately, 
no experience of it, but it appears to me that it is open to the same 
objections as brushwood burning. It is probably cheaper. 
The real difficulty in fighting Hylastes lies in the unsatisfactory condition 
of forestry in Scotland. Each estate has its own methods, and when there 
is a possibility of the carefully managed forest becoming infested from a 
neighbouring badly managed one, it is not to be wondered at that both 
landowners and. foresters are inclined to leave their insect enemies alone, 
so long as their depredations are not alarming. Unfortunately this ladssez- 
faire attitude is involving considerable loss in our woodlands, a loss which, 
under the present circumstances, ought to be seriously considered. 
(Issued separately, 7th December 1917.) 
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