242 WEST VIRGINIA EXPERIMENT STATION. 



It is evident, however that the destructive sapwood borer 

 exerts a marked influence in hastening the death of the trees, 

 and it is not improbable that in some cases they may cause, 

 on their own account, the death of trees which otherwise would 

 survive. 



WOODPECKERS ARE THE PRINCIPAL ENEMY OP THE DESTRUCTIVE 



SAPWOOD BORER. 



The trees that have been infested by the destructive 

 sapwood borer are readily distinguished from those 

 that are not, by the numerous holes in the bark and 

 wood, made by the birds searching for the grubs. The 

 punctures by the birds also offer additional opportunity 

 for the lodgment and entrance of the fungus germs. The pres- 

 ence of the woodpecker's work, especially if common, is there- 

 fore a fairly reliable indication that such trees are more or less 

 decayed, which evidence of unsound trees may be utilized to 

 some advantage by timbermen. Another remarkable and in- 

 teresting fact observed with reference to the work and pres- 

 ence of this insect, is the absence of the bark beetle in the bark 

 of the tree infested by the bark and sapwood borer, showing 

 that the conditions that are favorable for the attack of the 

 bark beetle, are not favorable for the attack of the borer, and 

 vice versa. vVhen both were found infesting the same tree, 

 which was rare, the bark beetles occupied one side of the trunk, 

 while the borer occupied the other. 



It would therefore appear that the destructive sapwood borer 

 is capable of doing much mischief, both in contributing to the 

 death of the trees and the rapid decay of the wood, and that in 

 this section, at least, it is the cause of serious loss of valuable 

 timber. 



PRESENT CONDITION AS TO INSECT ENEMIES. 



Kecent observations lead us to the conclusion that the liv- 

 ing spruce throughout the area is at the present time in a 

 healthier condition and freer from damage by insecls than it 

 has been for many years. This healthy condition of the timber 

 is due to the recent disappearance of its greatest insect enemy 

 the destructive pine bark-beetle and to the extensive and 

 continued cutting of the timber which furnishes, in the felled 



