FUNGUS GROWTH ON TREES 107 



the attacks of this insect go on from year to 

 year, and as usually almost every leaf is affected 

 and drops off prematurely, the health of the 

 tree is greatly enfeebled, and it thus becomes an 

 easy prey to the still more destructive coral 

 spot fungus (Nectria cinnabarma). 



Considerable difficulty has been found in 

 keeping this fungus in check. By burning the 

 affected leaves before the spores are liberated 

 in spring, the spread of the fungus is to some 

 extent prevented. 



As showing how carefully all diseased leaves 

 and twigs should be destroyed, the following 

 case may be pointed out. A badly infested 

 tree was cut down and removed, but the leaves 

 of the young shoots that were sent up from 

 the old stump during the following season 

 were as badly attacked as those on the original 

 specimen. 



The "Witch's broom" of the birch, or " birch 

 balls," is due to the attacks of the parasitic 

 fungus Taphrina turgida. It forms twiggy 

 clusters with comparatively small foliage, which 

 usually present a greyish colour on the under 

 sides in particular. As prevention is out of 



