The Portland daily press., 1891-08-13
DESTROY The cocooNs.
How to Rid the Trees of the Pest OF
Caterpillars.

The American Vaporer Moth, Orgyid Leu
costioma, is the species of caterpillars now
most abundant in Portland. and they are
very destructive to shade and fruit trees and
the foliage Of various plants. In 1882 and
1888 a number of trees were killed by these
caterpillars, but the pest was abated by
adoption of suggestions Of the writer, aided
by the city government and the mayor, who
issued proclamation urging citizens to act
on the suggestions by continued united eff
forts.
The newspapers gave valuable aid by call
ing public attention to the subject and the
ways and means most effective in abating
the nuisance.
Last year observed that this species was
increasing again, and this year the caterpil-
lars are quite abundant, giving occasion LOT
repetition of my suggestions to wage war
fare that will check and abate the impend-
ing danger to the trees. Destruction OF the
cocoon before the moth emerges is most ell
fective. The brownish white cocoons are
placed upon the bark of the trunk and large
limbs of trees, also upon buildings and
fences. especially in angles of cornices and
fence rails, and can be removed by means OF
stiff brushes and poles. with the aid of lad
ders. They should be gathered and burned
or otherwise destroyed, and the work re-
peated as successive cocoons are formed.
This orgyia is one of the most beautiful as
we'll as the most destructive of the caterpil-
lars known in North America, and Is very
easily identified
The caterpillar, when fully grown, is about
an inch and half in length, rather slender,
of a bright yellow color, its sides covered with
fine long yellow hairs; the head and two
warts on the ninth and tenth segments are
bright red; blacklist plumes of hair extend
forward from just behind the head, and sim
liar plume extends like tail from just before
the terminal segment of the body. There
are four brnsh-like yellowish tufts on top Of
the fourth, fifth, sixth and seventh segments.
Soon after arriving at perfect maturity the
caterpillar entombs itself in its cocoon. The
female moth that energies from the cocoon
is of a grayish color, oval in form, about
three-fourths of an inch in length and wing
less.
Very soon after the female is delivered
from the cocoon she is visited by the winged
male moth. which is of a grayish color, and
has an expanse of wings Of about an inch
and quarter.
The female deposits from 800 to 500 eggs,
one-twenty- Of an inch In diameter,
white, with slight yellowish depression.
and apparently smooth, except as viewed
under microscope.
The eggs are deposited in cluster, often
upon the outside Of vacated cocoon. From
these eggs are Matched the myriads of young
caterpillars that feed upon the softer part Of
the leaves Of the various trees and shrub
berry. The caterpillars grow rapidly and
their appetites in proportion, so that after
skeletOnizing leaf they recommence at the
edge and eat all up to the midrib. A tree
thus stripped of its foliage often puts out
new leaves. only to be destroyed in like
manner, until the vitality Of the tree be-
comes exhausted and 1t dies.
During the growth of the caterpillar its
skin is shed, perhaps several times, and
these cast-off skins may be found adhering
TO the under side of the leaves.
Two or more generations are brought
fourth in one season. The last lot Of eggs
deposited in the autumn does not hatch un-
til the following spring. The young cater
pillars are small, dark colored and incon-
spicuous as compared to the handsome, high
ly colored, mature. hairy caterpillars Of the
the same species, now seen in abundance
crawling on fences, buildings and trees.
seeking place to weave their shrouds, the
cocOons.
Much may be done to check the pests and
avert a greater danger from next year II
every householder and the custodians of our
trees and parks will join in destroying the
cocoons. EVERETT SMITH.
Portland, Me-, August 18th, 1891.