96 BOARD OF AGRICULTURE. [Pub. Doc. 



insect's work. Having drilled its burrow to a uniform diam- 

 eter, the insect ascends to the upper end, packs itself se- 

 curely in an elliptical chamber, and pupates. In 1897 the 

 writer collected a large number of infested sticks of poplar, 

 and examined them daily from June 30 to July 31. In a 

 single stick, one and one-half inches in diameter and two 

 feet long, he found 57 larvae. Some of these sticks were 

 split open each day, and on July 3 and 4 about all the larvse 

 were found to have pupated. By July 22, mature beetles 

 were found in the wood, although emerging did not take 

 place until about July 31. This would give us about eigh- 

 teen days as the length of the pupal stage. 



The beetles appear all through the months of August and 

 September, and, after feeding for some weeks upon the ten- 

 der petioles, deposit eggs for the brood of the following 

 season. In young, rapidly growing trees, with an abun- 

 dance of tender wood, the development of the insect is as 

 detailed ; in older trees a part of the beetles do not emerge 

 until the second spring. This gives us the straggling im- 

 agoes that have so confused students of the life history of 

 this insect. 



This pest is not amenable to treatment by spraying, so 

 far as at present known. The best method of treating it is 

 to dig out the young borers in the early spring, when they 

 are still at work in the bark, where their black burrows can 

 be detected by careful observation. 



Trees infested with this insect are weakened, and are 

 easily broken down by ice storms. This insect gives us 

 another illustration of the folly of planting only a single 

 variety of shade tree. The silver maple, the three-thorned 

 accacia and the elm make good growth in localities where 

 poplars and willows are most grown for shade or ornament, 

 and are not subject to attack by this weevil. 



It is difficult, in a paper of this kind, to select those in- 

 sects that are most injurious without excluding species of at 

 least considerable local importance. Should all important 

 shade-tree insects of the State be considered fully, the next 

 winter meeting of the Board would find us not far removed 

 from the meadow city. The writer believes that the insects 



