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tbe-year previous, I took out three full grown larvje, and found that it 

 had been bored from the top down to the root, killing it of course. 

 All sorts of trees are attacked by the insect, but not all trees succumb 

 with equal readiness. Vigorous varieties like the Kieffers resist for a 

 long time, and the burrows of the larvse become filled \i]) with new 

 tissue nearly as fast as they are made. Bartletts and Seckels do not 

 seem to have the same amount of vitality, and the wood and bark 

 immediately around the burrows dries and dies off, the bark cracking 

 on the outside and indicating, by its appearance, the presence of the 

 larva and the course of the burrow. Trees 40 years old, and which 

 have yielded annually large crops of fruit, are now dying off in great 

 numbers, and will probably be entirely gone in a very brief period. 

 The insect requires living tissue for its nourishment, and never under 

 any circumstances works in dead or dry wood. In two or three 

 instances I carried infested wood with me to the laboratory, but in 

 all cases the larvic died just as soon as the wood lost sap, and no 

 specimens came to maturity. I was equally unfortunate where I had 

 an entire tree sent me, most of the larvae dying, although here I 

 obtained one mature insect, a pupa having evidently been already 

 formed. This is really the most serious threat to j)ear (;ulture in the 

 district where the insect has thus far made its appearance. Fortu- 

 nately it has not yet spread over any very large extent of territory, 

 and there is no indication at present of any very rapid extension of its 

 injury. It seems to be confined, -so far as I can make out, to a terri- 

 tory not exceeding 10 or 15 miles in diameter; but within that point 

 it is extremely destructive. It was an extremely discouraging feature 

 this spring to visit orchard after orchard where there were numerous 

 trees well kept and cared for, carefully fertilized, and where in pre- 

 vious seasons good crops had been raised, and to find that on sound 

 trees the midge infested a very large percentage of the fruit, and that 

 where the midge did not attack everything, the boreis were working 

 in the trunks, and that the trees were losing vitality and were on their 

 way to the grave. There certainly was no encouragement to the farm- 

 ers, and unfortunately I had very little consolation to offer. Borers 

 of this description are among the most difiicult insects to deal with, 

 and apparently preventive measures only are indicated. Even they 

 are difiicult in this case, because the beetle lays its eggs anywhere on 

 the tree, and is not confined to the trunk or to the larger branches. I 

 have found shoots less than half an inch in diameter infested by larvte, 

 and they work down from that i^oint toward the trunk, and in the 

 trunk work down toward the ground in every instance. I presume 

 that mechanical coatings to the trees might offer some benefit, but it 

 is a practical impossibility to cover not only the trunk but all the 

 branches in such a way as to prevent the entrance of some larva?, and 

 once under the bark, the work will go on without danger from any 

 application that we can make, or even without discovery until the 



