MAPLE BORERS. 379 
August and September, so as to drive off the beetles and to destroy the 
freshly-hatched grubs, but since discovering how easily the grubs and 
castings of the freshly-hatched worms can be detected a few days or 
weeks after the eggs have been laid, it seems obvious that the easiest 
and surest preventive is to cut out the grubs when lying in their 
autumn and winter quarters just under the surface of the bark. It is 
almost impossible to destroy the fully- grown worms in their "mines" 
or burrows, since the latter extend up the tree either directly under the 
bark or are sunken in the wood. On one tree nearly destroyed by this 
borer, out of about fourteen mines twelve extended upward. Hence it 
is useless to try to find the hole and inject oil into it. There now seems 
no reason why valuable shade maple trees should not be saved by a 
few hours' close observation and removal of the young grubs, say in 
September or October. 
The beetle is black, with a yellow head, with the antennae and the eyes reddish- 
black ; the thorax is black, with two transverse yellow spots on each side ; the wing- 
covers for about two-thirds of their length are black, the remaining third is yellow, 
and they are ornamented with bands and spots arranged in the following manner : a 
yellow spot on each shoulder, a broad, yellow, curved band or arch, of which the yel- 
low scutel forms the keystone on the base of the wing-covers; behind this a zigzag 
yellow band forming the letter W, across the middle another yellow baud arching 
backwards, and on the yellow tip a black curved band and spot; legs yellow, while 
the under side of the body is reddish- yellow, variegated with brown. Nearly an inch 
in length. (Harris.) 
2. The horn-tail borer. 
Tremex columba (Linnaeus). 
Order Hymenoptera. ; family Urocerid^e. 
Boring in the trunk and making large round holes, a large white grub with a promi- 
nent spine on the end of the body, and transforming in the late summer into a large 
clear- winged saw-fly, with a long large " saw" on the tail of the female. 
This interesting insect bores indifferently in various forest and shade 
trees, attacking the elm, oak, sycamore, and perhaps more commonly the 
maple. The holes of this borer may be recognized by their large num- 
bers within a given space, and by their regular, evenly-cut shape, being 
about the diameter of a lead-pencil. We remember seeing some years 
ago a tree at Saratoga Springs, in the trunk of which, where the bark 
had been removed, were a dozen or more of the round even holes made 
by these insects, which seem to work some vhat in concert. Isolated 
shade trees along roads and in streets are favorite habitats. Harris 
says that an old elm tree in his vicinity used to be a favorite place of 
resort for this saw-fly, numbers of them collecting about it during the 
months of July, August, and the early part of September. " Six or 
more females might frequently be seen at once upon it, employed in 
boring into the trunk and laying their eggs, while swarms of the males 
