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Ibeg'an my studies on the insect pests of the blackberry in the early 

 part of the present year, before yet the canes had begun to leaf out, and 

 found that all the pests infested cane or root. 



■ One of the chief pests is the well-known Agrilns ruficoU is, or red- 

 necked blackberry cane-borer. Its life history has been worked out by 

 others, and I have nothing of any importance to add. The well-known 

 galls usually indicate the position of the borer, and how to get rid of it 

 is the question. 1 say the galls usually indicate the ])osition of the 

 borer, because, though there can be no gall without a borer, we can 

 have a borer without a gall. If a gall be split the length of the cane 

 it will be seen that the wood is not involved in the gall growth, but 

 onl3^ the bark. The insects emerge from the canes in early summer. 

 May 25 to July 10, the month of June being the time of greatest abun- 

 dance. The egg is laid by the female at the base of a leafstalk, and 

 I believe it is not thrust into the tissue, but is simply laid at the base 

 of the stalk or in the bud there starting. It was not until late in July 

 that any larva3 were found. The first sign of their presence was a dead 

 bud at the leaf axil, and where the stem was carefully examined al- 

 most every dead bud showed traces of having been eaten into, the 

 minute and very slender young larva being found under the bark 

 near by. 



Usually they run up the main shoot ; but where laterals have become 

 well developed, they often go into these, especially where more than 

 one egg was laid in the same place. In neglected fields, often as many 

 as three eggs may be found at a single point, and five leaf axils may be 

 infested on a single stalk. The young larva bores upward in a cork- 

 screw channel in the sap wood, as much in the bark as in the wood, 

 until early August. Some are at that period only one-fourth of an inch 

 long and almost nothing in diameter, while others are half an inch in 

 length and reasonably stout. Sometimes a larva will make only two or 

 three long circles around the cane and then, while yet minute, will 

 pierce the cane and get into the pith. Where this is done, no visible 

 gall forms. Others, however, and usually those in large, stout canes, 

 will circle the stalk half a dozen times or more in succession, the girdles 

 not more than one-eighth of an inch apart. The first trace of a gall I 

 found in early August, when a slight ridge appears over every larval 

 gallery, so that the course of the borer is perfectly traceable on a smooth 

 stem. As the cane grows the sawdust and excrement in the galleries 

 seem to swell and enlarge and also to destroy the vitality of the tis- 

 sues around it, until, instead of the girdlings becoming smaller, they 

 really become more prominent, and the abnormal growth of tissue con- 

 tinues. In some cases, as stated, no galls appear; but this is some- 

 what exceptional. In raspberry I have not found the galls, while bor- 

 ers have been found not rarely. This indicates that some of the exempt 

 varieties of blackberries may simply form no galls. I am the more 

 inclined to believe this, because I have seen beetles in no small uum- 



