134 PROTECTION OF WOODS AGAINST 



tree. A great number of cankers may appear on the same 

 tree. When the canker is high up, or when the tree is 

 vigorous and is growing under favourable conditions, it will 

 probably overcome the disease, or at any rate the tree will 

 live on for years ; although of course the timber is spoilt at 



Fig. 12. Portion of Larch- stem attacked by Dasyscypha calycina, Fuckel. 

 a Cracks with outflow of resin. b Fructifications. 



the canker. When young trees are attacked low down, and 

 when the soil and climate are not suitable for larch, the tree 

 will probably die before many years have passed. From a 

 few infected trees the disease will spread throughout a young 

 plantation, the spores germinating if they settle on a wound 

 however small. Such wounds are always present on the 



