Page:The Zoologist, 3rd series, vol 2 (1878).djvu/367

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OCCASIONAL NOTES.
343

the following extracts, which we have no doubt will he read with interest:—"Proprietors of pine forests often destroy Capercaillies in the doubtless just belief that they do considerable damage to the trees by picking out the leading buds, thus dwarfing and rendering the tree unfit for timber. Some naturalists, and proprietors of forest land as well, assign the results of stunted growth, turfy appearance of young trees, and deterioration of Scotch fir in this country to one or both of two other causes : — (a) The importation of impure seed, and hybrid ' strains,' causing an inferior growth of less healthy wood, less able to stand the rigour of late frosts than the native and undegenerate Scotch fir, which latter is still to be found in some parts of Scotland, although native and healthy seed is scarce, or becoming so. It has been the fashion, too, of late years purposely to plant stunted and inferior kinds to provide cover for game, (b) The ravages of insects, principally beetles. Of these, Hylurgus piniperda attacks the cores of the buds and young shoots, piping the latter, and causing the former to drop off, stunting the growth of the trees, and making them bushy and useless. Another species bores into the wood and back of the stem, not to speak of ten or a dozen other beetles, as well as Tenthredinidæ, Nematus, Coccus, and their larvæ, which feed upon the leaves. The actual work of destruction carried on by the bird and by the insects may perhaps be easily distin- guishable in most, if not in all, cases ; but the results in after years to the trees cannot always be so easily assigned to the work of any one of them. To these two causes perhaps a third may be added with safety, — improper exposure, insufficient drainage, unsuitable soil ; in short, bad forestry, and late frosts and bright suns acting upon unacclimatised or inferior plants, no doubt in some cases has something to do with it. Arising from these facts is the question whether these insects or their larva?, individually or collectively, attack truly healthy native trees equally with diseased or inferior foreign importations. In answer to this we have Mr. Dunn's evidence that they do, but he only speaks of one out of many pine- destroying species, viz., Hylurgus piniperda. He informs us that this beetle for the most part attacks trees under twenty-five years of age. If, as he affirms, Capercaillies only attack trees which are healthy, its attacks some day will be confined to trees above that age, if the Hylurgus become very populous throughout our forests. Notwithstanding strong evidence to the contrary from Mr. Dunn and Mr. Brown, of Perth, Capercaillies feed largely upon insects. This is specially the case when birds are young, but the probability is that grown birds do so also at certain seasons. We have seen that young birds feed largely upon the larvæ of Tenthredinidæ and other insects, and insect larvae which live upon or are destructive to pines. The questions of interest arising from these facts are : — What appreciable damage can be laid to the charge of the insects, individually or collectively, or their larvæ? Mr. Crawford, manager on the property of Clathick,