[Illustration:  FIG. 102.—­The Gipsy Moth. (After F.W.  Rane Mass.  State Forester.)]

[Illustration:  FIG. 103.—­The Brown-tail Moth. (After F.W.  Rane, Mass.  State Forester.)]

[Illustration:  FIG. 104.—­Larva of the Leopard Moth.]

THE FALL WEBWORM

The caterpillars of this insect congregate in colonies and surround themselves with a web which often reaches the size of a foot or more in diameter.  These webs are common on trees in July and August.  Cutting off the webs or burning them on the twigs is the most practical remedy.

[Illustration:  FIG. 105.—­Branch Showing Work of the Leopard Moth Larva.]

THE LEOPARD MOTH

Life history:  This insect does its serious damage in the grub form.  The
    grubs which are whitish in color with brown heads, and which vary in
    size from 3/8 of an inch to 3 inches in length (Fig. 104), may be
    found boring in the wood of the branches and trunk of the tree all
    winter.  Fig. 105.  The leopard moth requires two years to complete
    its round of life.  The mature moths are marked with dark spots
    resembling a leopard’s skin, hence the name.  Fig. 106.  It is one of
    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.