228 OUR FORESTS AND WOODLANDS 



as to be quite spoiled for the production of 

 valuable timber; and there can be no hope of 

 stamping out the disease. The best thing that 

 can be done is to exercise care in the selection 

 of localities for growing it, in which respect a 

 northern aspect most resembles the alpine climate ; 

 to grow it only on suitable soils, such as good, 

 deep, fresh limes or loams and the better classes 

 of sands ; and to raise it in mixed crops rather 

 than in pure plantations. Neither tenacious clays, 

 nor binding limes, nor poor soils, nor land that 

 can be classed between moist and wet, are favour- 

 able to its good growth and healthy development. 

 Under any adverse circumstances, but especially 

 when growing on uncongenial soil or on a hot 

 exposure without depth enough to accommodate 

 its deep tap-root properly, its natural vigour is 

 diminished. It is then most apt to be attacked by 

 the larch aphis (Chermes lands') and the mining 

 moth (Coleophora laricella), the injuries made by 

 which form wound-spots soon infected by the 

 canker-producing Peziza fungus. 



Larch develops a very strong tap-root, hence 

 depth of soil is essential for its best growth. It 

 is the most light-demanding of all our forest 



