Fungus Growth on Trees 217 



ous blotches for which affected trees are remarkable. Both 

 species are sometimes found on the same leaf. As the 

 attacks of this fungus continue from year to year, and cause 

 almost every leaf to drop off prematurely, the health of the 

 trees is greatly impaired, and they become an easy prey to 

 the still more destructive coral spot fungus, Nectria cinna- 

 barina. By burning the leaves affected with Rhytisma 

 before the spores are liberated in spring, the spread of the 

 fungus is prevented in a simple and effective manner. 

 The sycamore fungus is very plentiful on trees around 

 London. 



The canker of hard- wooded trees is brought about by 

 one of the Nectria (N. ditissima), and is very common in 

 every part of the country, affecting the oak, beech, ash, 

 sycamore and fruit trees generally. The ash perhaps 

 suffers most, the timber turning black and being quite 

 unfitted for structural purposes. It is strictly parasitical, 

 growing on wounded portions of the stem and branch, and 

 spreads with great rapidity, attacking trees of all ages. We 

 have known the trees in a plantation of ash to be quite 

 destroyed by this canker, which attacks most freely those 

 growing on wet, sour land. This should be a warning to 

 planters to avoid such soil. 



The Red-rot Fungus (Fomes annosus or Trametes 

 radiciperda) attacks the roots of several species of pine, 

 particularly the Scotch, Corsican and Weymouth, as also 

 the Spruce and Silver Fir. It is probably the most destruc- 

 tive of the family, attacking living roots and spreading 

 rapidly from tree to tree. The trees, when affected, quickly 

 turn sickly and die, the wood becoming spongy and of a 

 brownish colour, with distinct black spots. The only 

 remedy is to take out affected trees and burn them root 

 and branch, replanting the ground with beech or elm. 

 Though one of the most destructive fungi in coniferous 

 woodlands, its attacks are by no means confined to these 

 alone, since it is found on the roots of several hard- 

 wooded species, such as the filbert, hazel, birch and 

 beech. Quite recently a nut plantation in Kent suffered 

 seveiely from the attacks of this fungus, whole lines of 



