BEECH DISEASES 107 



Cause. 



The common yellowish sapwood-rot of beech and yellow birch 

 is caused by Fames fomentarms. Spores drop out of the tubes 

 on the under side of the sporophores and are blown away. Any 

 wound in the bark exposing the sapwood furnishes a suitable 

 place for these spores to germinate and start a new mycelium. 

 The elements of the wood are largely destroyed, leaving a loose 

 mass of easily crumbled fibers. The effect of such a sapwood- 

 rot on the life of the tree is more serious and quickly destructive 

 than when equally extensive areas of the heartwood are de- 

 stroyed. The decay of the sapwood interferes with the trans- 

 portation of food materials and water, and thus produces the 

 same effect as mechanical girdling. After the tree dies, the 

 fungus works very rapidly as a saprophyte and destroys the re- 

 maining wood. For further details concerning the life history 

 and control of the wood-rotting fungi of living trees, see page 64. 



Reference 



Sohrenk, Hermann von, and Spaulding, P. Decay caused by Fomes 

 fomentarius. In Diseases of deciduous forest trees. U. S. Dept. 

 Agr. Bur. PI. Ind. Bui. 149 : 50-51. 1909. 



Common White Wood-Rot 



Caused by Fomes igniarius Fries 



This white wood-rot is a common and destructive disease of 

 beech. Many other kinds of deciduous trees are subject to the 

 same disease, principally poplar, oak and maple. In the Adiron- 

 dack Mountains as much as ninety per cent of the second growth 

 is sometimes made worthless for timber by this wood-rot. The 

 decay may extend outward into the sapwood and cause the death, 

 of the parts above. The characteristics of the sporophores and 

 the decay are similar for all kinds of trees affected and are de- 

 scribed more fully under poplar diseases, page 305. 



