Insects Injurious to the Apple. 



Ill 



THE FRUIT BARK BEETLE. 



(Scolytus ruyulosus. Eatz.) 



The damage caused by this Bark Beetle seems to be on the 

 increase. It is recorded from Devon, Worcester and Kent. Writing 

 in July 1906, Mr. Lewis Levy of Borden Hall, near Sittingbourne, 

 says : " We have a plum tree which has just died, and find numerous 

 tunnels between the bark and the wood, and also in the latter." The 

 specimen sent and the damaged wood, proved the culprit to be 

 Sculytus ruyulosus. Numerous trees were observed in Worcestershire, 

 several of which had been killed, and 

 others were dying from the effects of this 

 Bark Beetle. 



The worst attacked specimen seen was 

 sent me by Mr. Gardner of Ombersley, 

 who very wisely destroyed the infested 

 trees. Part of this tree given me is repro- 

 duced here (Fig. 93). 



The beetle has somewhat varied food. 

 It seems to have, however, a decided 

 preference for apple and plum. I have 

 seen pears similarly attacked, but never 

 cherries. 



The Board of Agriculture Leaflet 

 (No. 49) says also peach, apricot, nectarine 

 and quince. In some cases it seems that 

 the beetles prefer to oviposit in the 

 smaller branches and twigs, which thus 

 wither and die. The leaves soon show 

 signs of their presence by wilting, dying 

 later and turning brown ; the bark then cracks and eventually 

 peels off. 



Most cases recorded and seen during the past few years have been 

 attacks on the stems of trees from eight to fifteen years old. In one 

 case the whole stem from five feet above the ground into the branches 

 was riddled with shot holes the " flight holes " of the beetles. 

 Whilst on the smaller boughs and twigs the bark readily cracks and 

 splits off, that on the stem was noticed to remain in its normal 

 position. On removing the bark one finds that the shot holes lead 

 down through it to the wood, in the soft sappy layer of which the 

 larval scolyti may be seen working and sculpturing galleries, which 



[flora 



FIG. 92. 

 URK BEETLE (ScolytUS 



