328 NOTES ON BRITISH FOREST TREES. 



Insects and fungi are not very formidable. The leaves 

 of the ash tree are rarely injured except by Chrimatohia 

 bntinata, and in Central Europe by the ])lister-beetle, l.t/lfx 

 vi'sinitnria. The shoots are sometimes much stunted by the 

 larvfe of a Tineid moth, Piay>f nirtisi'lhi. The bark is sought 

 and badly gnawed by the hornet. The Coss'nhf readily attack 

 it, ZcKzera preferring the saplings to any other food plant. 

 The bark-beetles, ILih'ainHs fraxini and cnniatiis, kill sickly 

 trees ; the former also attacks the upper branches of healthy 

 trees and kills them in a few years. 



Cankerous spots in the bark may ])e caused by Xictria 

 (Utissima. 



The thinnings of ash woods should be such as to enable the 

 tree to lay on diameter increment, in other words to give it a 

 liberal growing space at all times, and especially with 

 advancing age, 



i). Elm — Ulmus (L.). 



The following two species will here be noticed : — 

 (1.) The common elm= Ulmus campestna, Sm. 

 (2.) The Scotch, wych or mountain e\vQ.= UhnH>i nioitUina, 

 Sm. 



a. Vlilili/. 



Elm yields a coarse timber which is hard, moderately 

 heavy, difficult to split, very durable, even when exposed 

 to become alternately wet and dry. Specific gravity of air 

 dried common elm', mean = '73, of mountain elm = -(il). It 

 is used for a great variety of purposes in rural districts, 

 by the carpenter, joiner, wheelwriglit, turner, boat-builder, 

 and others. It yields a fair firewood, and the leaves are 

 good foddei-. The ashes yield excellent potash. 



h. hislrlbiilion. 



Common Kim. — Central and South I'hirope, North Africa 

 and Siberia ; goes up to 4,000 feet in the Alps. It is found 

 in England up to an elevation of l,r)00 feet in Derbyshire, 



