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the year previous, I took out three full grown larvae, 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 larvae become filled up 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 oft' 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 larvae 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 pear culture 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 borezs 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 difficult insects to deal with, 
and apparently preventive measures only are indicated. Even they 
are difficult 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 larvae, 
and they work down from that point 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 larvae, 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 
