the commonest and most destructive insects in the East and is
responsible for the recent death of thousands of the famous elm
trees in New Haven and Boston. Fig. 107.

[Illustration: FIG. 106.--The Leopard Moth.]

Remedies: Trees likely to be infested with this insect should be
examined three or four times a year for wilted twigs, dead branches,
and strings of expelled frass; all of which may indicate the
presence of this borer. Badly infested branches should be cut off
and burned. Trees so badly infested that treatment becomes too
complicated should be cut down and destroyed. Where the insects are
few and can be readily reached, an injection of carbon bisulphide
into the burrow, the orifice of which is then immediately closed
with soap or putty, will often destroy the insects within.

[Illustration: FIG. 107.--Elm Tree Attacked by the Leopard Moth.]


THE HICKORY BARK BORER

Life history: This insect is a small brown or black beetle in its mature
form and a small legless white grub in its winter stage. The beetles
appear from June to August. In July they deposit their eggs in the
outer sapwood, immediately under the bark of the trunk and larger
branches. The eggs soon hatch and the grubs feed on the living
tissue of the tree, forming numerous galleries. The grubs pass the
winter in a nearly full-grown condition, transform to pupae in May,
and emerge as beetles in June.