Insects Injurious to the Apple. 



127 



AN EMPHYTUS SP.? ATTACKING THE APPLE. 



A single case only of this insect attack has been brought to my 

 notice, and I can find no reference to it in literature.* A well- 

 known grower, Mr. H. F. Getting of Ashfield Park, Eoss, wrote in 

 Xovember: "I was startled to find a number of my young apple 

 trees with a round hole in the top of last year's growth (i.e., where 

 branches were pruned to). On examination I found that green 

 caterpillars were doing the damage. This is quite new to me, and I 

 am afraid may be a serious pest." 



The culprit proved to be one of the Sawflies belonging to the 

 genus Emphytus. 



The Iarva3 enter the pith cavities to pupate, and in doing so they 



\F. V. Theobald. 

 FIG. 102. LARVA OF THE APPLE EMPHYTUS (Emphytus Sp. ?) 



c, larva in situ ; b. entrance of tunnel ; a, excrement. 



may be the cause of much damage, as many of them seemed to bore 

 down below the point of origin of the side shoot, and this not only 

 weakens its growth, but may destroy it entirely. Mr. Getting 

 noticed that they preferred to attack the main shoot, doubtless owing 

 to the pith cavity being larger. Their presence may easily be 

 detected by the " frass " and granular pith thrown out, which collects 

 on the pruned surface as a fine dust (Fig. 102 a). 



Mr. Getting's further observations are as follows : " After it has 

 made the hole sufficiently deep, it turns round with its head towards 



* The following account is taken from my Report on Economic Zoology for 

 the year ending April 1st, 1905. 



