St. Johnsbury Caledonian. [volume] (St. Johnsbury, Vt.) 1867-1919, 1898-06-15
Forest Tent Caterpillar.

The experiment station have issued the
following circular upon the caterpillar
pest:
This insect which was quite destruc-
tive last year has again appeared at
several points and is reported as doing
great damage particularly to the maple
and apple trees. A full description with
remedies was published some months
ago by the Vermont Experiment Station
in Bulletin 60, from which the following
description is condensed:
The forest tent caterpillar may flourish
for some time in forests before it attracts
attention, and then may suddenly MI
CRATE to adjacent orchards where it ap-
pears very unexpectedly in large swarms.
This insect confines its ravages mainly
to the apple and sugar maple. 1t was
widely distributed over the state. In
most places it was quite destructive. In
some orchards the caterpillars are said
to have been so numerous as almost to
cover the trunks of the trees.
Description: The caterpillars when
first Matched are minute black worms,
usually creeping about in companies,
and when moving some distance doing
so in single file. In about two weeks
they are of yellowish brown color, and
later begin to take on the colors of the
mature insect. The fully grown cater
pillar is somewhat hairy worm, about
two inches long. The body is blush
above, changing on the sides to greenish,
while underneath it is dark, the legs
being nearly or quite black. The whole
body is thickly sprinkled with black dots
and bears several light longitudinal
lines. A line of light spots along the
back is conspicuous. A wide yellow line
and whitish band extend along each
side. Short, light, yellowish. brown
hairs are sparsely scattered over the
body. On each joint, except the eleventh,
there are two black, shining tubercles
from which arise few fine black hairs.
The caterpillar becomes mature about
the first week in June. At this time they
cease feeding and do not, as before, collect
in groups, but wander singly over the
tree, or sometimes away from it in search
of shelter from the cocoon.
Food. 1t is more general feeder than
is the common tent caterpillar and feeds
on all our common fruit trees, and on
naples, oaks, wanuts, poplars, ash, etc.
In some places it prefers the apple to any
other tree, in Others it only attacks the
sugar maple. Again these trees are
largely neglected and the oak is sought,
elsewhere it is the poplars that suffer
most. In all cases there is loss of needed |
foliage and corresponding injury done
the tree.
Remedies. Often the best remedy which
can be used against injurious insects is
prevention, and this is emphatically so i'll
the present case. Prevention, however,
is not always possible and remedies must
be used. After the caterpillars have be-
come established in grove or orchard
it is not easy to dislodge them. Now
that the worms are nearly full grown
and the nests conspicuous many may be
destroyed by the torch. A rag wound
about the end OF pole, fastened by bit
of wire and soaked with kerosene NAV
be applied both to the nests and to the
clusters of worms. 1t may be necessary
to go over the trees a second time. II,
as may very likely occur, they gather in
clusters OIL the trunk they may becrushed,
and this should be done promptly for the
opportunity may not come again. The
NAdSNSio diS LhOoI lOTIneu Ill |
early morning or at dusk. A much less
efficient method, but one which may be
at the time the best which can be fol-
Owed, is that of vigorously Earring the
branches on which the worms are located.
As they let themselves down by the
thread they spin, they can be gathered
N pan of kerosene by sweeping a twig
back and forth underline branch. Spray
ng the trees with paris green or other
arsenite will sometimes be found an ef.
ectual and convenient remedy. On the
whole, however, prevention by destruc-
lion Of the egg clusters is better than any
'ernedy. If the trees are carefully ex-
amined during the fall or winter, the egg
clusters may readily be seen and can be
by cutting off the twigs on
which they have been formed. Every egg
nassobtained lessons the number of cater