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that there are any living trees left. In fact, there are not many 

 left in some sections of these States where the tree was abundant 

 and healthy fifty years ago. 



It appears that there are a number of agencies of destruction 

 other than this new chestnut blight disease, and that these agen- 

 cies have been in operation in the area affected by the disease as 

 well as in areas where this disease is not known to occur. There- 

 fore, they must be taken into consideration and investigated 

 before the problem of protecting the chestnut can be solved. 



There appear to be other diseases and we know that there are 

 insects which have been directly or indirectly the cause of the 

 death of a large percentage of the chestnut over extensive areas. 



One species of insect, the two-lined chestnut borer, is perhaps 

 the most destructive insect enemy. It has been investigated 

 and methods of controlling it determined and demonstrated, 

 and there is no lack of published information on the subject. 



There is also a combination of insects and the chestnut blight 

 disease. Investigations by forest pathologists have revealed the 

 fact that the spores of the chestnut blight find their way into the 

 living bark through some wound and that the majority of such 

 wounds appear to be caused by bark-boring insects. 



Recent investigations by forest entomologists tend to verify 

 this general statement, and that a large number of species of 

 insects are involved. 



Inasmuch as the insects make a primary attack and the dis- 

 ease is largely dependent upon insects to continue its destructive 

 work, it is also plain that we have an insect problem of perhaps 

 equal importance to that of the blight itself. 



It is also plain that this interrelation of insects and disease 

 pivxents a new arid complicated problem which will require a 

 great deal of exact scientific research by the forest entomologists 

 and the forest pathologists before we shall be warranted in ar- 

 riving at definite conclusions, or in giving specific advice on 

 methods of control and prevention. 



Considerable work has already been done on the general sub- 

 ject of chestnut Insects by the West Virginia Agricultural Ex- 

 periment Station and the Bureau of Entomology of the U. S. 

 Department of Agriculture since 1893. The published and un- 

 published records of these studies show that three hundred and 



