BRITISH FOREST TREES 145 



attacks of caterpillars of Coleophora laricella and Grapho- 

 litha pinicolana on the foliage, and from the much more 

 serious fungoid disease occasioned by Peziza Willkommii, 

 which breaks out most frequently in the pole-forest stage of 

 growth (ten to twenty-five years), and more especially after 

 bad attacks of the above-named insects. With these ex- 

 ceptions the larch does not suffer much either from fungoid 

 diseases or insect enemies, although it shares the liability 

 of other conifers as regards the rot caused at the base of 

 trees by Agaricus melleus, and the canker in stem and 

 branches due to Trametes pint; red-rot is occasionally 

 generated by Polyporus sulphureus. 



Similar remarks obtain with regard to its resistance to 

 storms. In the Alps, its deep root-system, its leafless 

 condition during half the year, and the elasticity of its 

 branches and of the upper portion of the stem, secure it 

 comparative immunity from the violence of heavy winds ; 

 but on the lower hills, uplands, and valleys, where it has 

 often been somewhat indiscriminately planted, its power of 

 resistance is weakened, although this is still not to be 

 reckoned slight. 



It is eagerly sought after by roe and red-deer, and not- 

 withstanding great recuperative power, the damage done is 

 often considerable, as affording a favourable germinating bed 

 for the spores of Peziza. 



Sylvicultiiral Treatment of Larch. Even where indigenous, 

 the larch is much less frequently to be found forming pure- 

 forests of large extent than in groups or clumps along with 

 spruce, beech, and silver fir at lower elevations, or as the 

 ruling species in mixed forests containing spruce and moun- 

 tain pine towards the upper limit of vegetation. Thus the 

 pure forests that have been so frequently formed in Scotland 

 are at the very outset a departure from, and almost a contrast 

 to, its natural habit of growth. Its cultivation in the mouiu- 



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