WEST VIRGINIA GEOLOGICAL SURVEY. 



75 



damage the roots of trees in the same manner. These injuries, 

 like those caused by snow and ice, are important chiefly because 

 of the channels which they open up for destructive insects and 

 fungi. 



Injuries by Forest Fires. 



It should not be forgotten that one of the most serious ef- 

 fects of forest fires comes quietly and often unobserved, yet none 

 the less surely, from the work of numerous species of fungi that 

 are admitted to the wood of living and dead trees through the 

 injured bark. Millions of forest trees in the State have been 

 greatly damaged or rendered worthless by this secondary effect 

 of fire. 



Injuries by Insects. 



Insects must be classed among the worst of the enemies of 

 trees. They not only injure every part of living trees, but attack 

 and destroy fallen trunks and manufactured wood products. The 

 destructive work of forest insects is taken up more in detail un- 

 der another head. 



Injuries by Fungi. 



The destructive work of fungi has already been referred to 

 in a general way. The leaves, twigs, roots, bark and wood of liv- 

 ing trees suffer from fungous diseases of many kinds. It has al- 

 ready been pointed out, also, that after trees are cut down their 

 wood is in still greater danger from the fungi that produce de- 

 cay unless it is rapidly and thoroughly seasoned or treated with 

 some chemical preservative. 



Fungi and Their Methods of Work. 



The terms "fungous disease", ''bacterial disease", and the 

 like, would have been meaningless to the general reader in West 

 Virginia twenty years ago; but since the development of scien- 

 tific treatment of diseases of vegetables, grains, and fruits, this 

 is no longer the case. Through farmers' institutes and ag'ricul- 



