or the control of this insect. Some of them may be worth
trying; most are of doubtful value, and some are absolutely injurious to
the trees. On July 3, 1914, some affected hickory trees on the Station
grounds were sprayed heavily with powdered lead arsenate, 4 lbs. in 50
gallons of water, to which one pint of "Black Leaf No. 40" was added.
Two days later many dead beetles were found on the tar walks under the
trees, and a few were observed each day up until about the middle of
August. Most of the trees treated, however, had been so badly injured by
the insect that they were removed. Since then this insect has caused
little damage on the grounds, though a few hickory trees still remain.
In 1901 an outbreak of the hickory bark beetle caused the death of 110
trees on the Hillhouse place in New Haven; then the destructive work of
the insect ceased and the few remaining hickory trees are still standing
and in fairly good condition. I mention these instances to show that
nature's control methods through parasites and natural enemies is far
more effective with certain pests than any which man has yet devised. Of
course, we hope that in the future man will make better progress along
this line.
THE PAINTED HICKORY BORER.
_Cyllene pictus_ Drury.
There are several borers attacking the wood of the trunk of the hickory,
but one of the commonest is the painted hickory borer. It also
occasionally attacks black walnut, butternut, mulberry and osage orange.
In hickory especially the larval tunnels are often found in the wood
when trees are felled. There is probably one brood annually and the
winter passed in the pupa stage, though it may possibly hibernate as a
larva. Its life history is not fully understood. It is a common
occurrence in Connecticut, and specimens are sent me every year, for the
adult beetles to emerge in March from firewood in the house or cellar
and crawl about seeking a chance to escape. The housewife fears that a
terrible household pest has descended upon her, and with fear and
trembling invokes the aid of the Agricultural Station.
The beetles appear outside in April and May, and probably oviposit soon
afterward. They are about three-fourths of an inch in length and are
black, prettily marked with golden yellow.
The insect can be controlled only by the old arduous methods of digging
out, and injecting carbon disulphide into the burrows.
Several other long-horned beetles are borers in the hickory and ot
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