8 



AFFECTING THE CANES. 



Fig. 



S. The Red-necked Aqrilus {Agrilus ruficoUis, Fab). 



This insect was first described by the great German Entomologist 

 Fabricius, in the year 1801, but for very many years after this nothing 

 was known of its earlier or larval history. In 1846, Professor S. S. 

 Haldeman contributed a paper to the "Quarterly Journal of Science and 

 Agriculture" in which details of the injury it does to the Raspberry 

 were first given. More recently Prof C. V. Riley, in the second volume 

 of the American Entomologist" has given a fuller account of the opera- 

 tions of this insect, and from this source much of the following has been 

 condensed. 



In the spring-time when raspberry and blackberry patches are being 

 pruned, the canes will often be observed to swell out in places to th« 

 length of an inch or more in the manner shown in figure 2. This 

 swelling is a sort of pithy gall and has been named the Raspberry Gouty 

 Gall, E'uhi joodagra, Kiley, and is produced by the irritation caused by the 

 presence of the larvae of the Red-necked Agrilus. The swollen portion? 

 are not smooth like the healthy ones are, but have the surface roughened 

 with numerous brownish slits and ridges When these ridges are cut 

 into with a knife there will be found under each of them the passage 

 way of a minute borer. Figure 3 represents the little creature fully 

 grown on a magnified scale, the hair line at the side showing its natural 

 size. It is snaall, and with a body almost thread-like and of a pale 

 yellowish or whitish colour, but with the anterior segments flattened out, 

 somewhat like that of the larva of the common Flat-headed Apple-tree 

 Borer. Chrysohothris femorata, but in a less degree. The head is small 

 and brown, the jaws black, and the tail is armed with two slender dark- 

 brown processes or horns, each with three blunt 

 teeth on the inner edge. ' When full grown it mea- 

 sures about six tenths of an inch. In the earlier 

 period of its history it dwells chiefly in the sap 

 wood, and following a sort of irregular spiral course 

 frequently girdles and destroys the cane. Usually several of these larvae will be found in the 

 same cane, thus lengthening the gall and causing it to assume a very irregular shape. It is 

 said to infest the Philadelphia raspberry, the Doolittle black cap and the Wilson blackberry 

 worse than other varieties. In April or May the larva penetrates into the pith, where it is 

 more secure from insect and other foes, and there changes ipto the pupa state, and early in 

 summer the perfect beetle appears. It is probable that the sexes couple some time in July 

 and that shortly after this the female deposits her eggs on the young canes, where they hatch 

 out tiny young larvae, which^eating into the cane, in process of time, develope the mischievous 

 results already detailed. 



Fig. 3, 



Fig. 4. 



In figure 4 c we have the perfect insect magnified. 1 ' 

 is about three-tenths of an inch long, with a rather small 

 dark bronzy head, a beautifully bright coppery neck and 

 brownish black wing-covers. The under surface is C 

 uniform shining black colour. 



The best method cf getting rid of this troublesome 

 pest, is to cut out the iafested canes and burn them in spring 

 before the beetle escapes. 



3. The Raspberry Cane Borer (Oberea tripundata Fab.). 



This insect in the larval state lives in the centre of the cane, where it burrows a passage 

 upwards and downwards often causing the death of the cane. Its natural home is among the 



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