CHAPTER VIII 



ENEMIES OF CONIFEROUS TREES 



These are many and include the attacks of 

 animals and birds as well as of insects and fungi. 



Insects 



Pine Beetle [Hylesinus (Hykirgus) piniperda) 

 is a dread enemy to not a few species of Pinus, 

 but particularly to P. sylvestris, P. Laricio, P. L. 

 nigricans, and P. Strohus, The injury done by 

 this beetle consists in its destruction of the leading 

 shoots of the tree it attacks. It enters by boring 

 a hole into the side of the shoot until it reaches 

 the pith, after which the course is directed upwards, 

 and an exit made at the terminal bud. This 

 tunnelling of the shoot so weakens it that fre- 

 quently during stormy weather it is broken across 

 at the point where the beetle entered. Not only 

 are unhealthy trees attacked by the Pine Beetle, 

 but young and robust -growing specimens fre- 

 quently fall a prey to its insidious depredations. 

 June, July, and August are the months when it 

 is most commonly found. The only remedy is 

 collecting and burning the affected shoots — work 

 that requires to be done with the utmost care to 



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