Fungus Growth on Trees 



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affected tree. The only remedy is digging out and destroy- 

 ing the fungus, and, in the case of healthy young trees, 

 collecting and burning the mycelium. 



Next to the larch canker, one of the most destructive 

 diseases of forest trees is caused by attacks of the Bladder- 

 rust or Cluster-cup (Peridermium piniacicola). It is a 

 wound fungus and attacks almost every species of pine, the 



POLYPORUS SULPHUREUS (ON WHITE POPLAR) 



Scotch in particular, especially when the trees are growing 

 on light, poor soils. Young trees up to, say, twenty years 

 old are most commonly attacked by this fungus, which 

 appears like blisters, emitting bright reddish-coloured 

 spores. Rooting up and burning all affected trees is the 

 best remedy. 



Polyporus sulphureus attacks many species of trees yew, 

 poplar, etc. 



