TORTRIX BUOpAJ^A. 



3:3? 



The attack is made by the larva boring into buds and shoots. 

 Late in the summer the buds, particuhirly the terminal buds, 

 are slightly gnawed at their base, so that turpentine exudes. 

 In the following spring, as soon as the plant begins to shoot 

 up, the caterpillar bores right through the pith of the young 

 shoots. Shoots eaten on one side become curved as in the 



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Fig. 173.— Pine-braucli, showing distortion after antecedent injury by T. huolinna 

 Schiff. A larval gallery is exposed in the broken shoot, a. {Natural size.) 



figure, and if no further injury is done, will recover their 

 vertical position, but the perforated shoots dry up, turn brown 

 and fall ofif. After destroying the terminal shoot, the larva 

 directs its attention to the side shoots ; it sometimes spins 

 several together, and passes from one to another. The attack 

 can be distinguished from that of the pine beetle by the 

 crumbling excrement found in the borings. 



The injury causes the pine to send out brush-like shoots as 



F.P. Z 



