The Lake County star. [volume] (Chase, Mich.) 1873-current, 1875-07-01
Canker Worm.
From the forthcoming Report OF the State Agrlcu
turu Board OF Michigan rf

turui Board OF Michiganl ~
This insect has curious history
in our State; for though it has made
its appearance several times, once
in Calhoun county, again in Genesee
county and in other places, for the
past two or three years near Com
merce, Oakland county and just now
hear Pontiac, of the same county,
still it has never seemed to hold on;
for, after destroying "a few orchards,
it seems to succumb to natural en-
emies, or unpropitious circum-
stances, and ceases to cause even
anxiety. That it will be but tenn
porary evil among us is perhaps
asserting too much, yet l think it
plausible supposition; and it is
certainly earnestly to be hoped.
Our New England friends have had
to fight this insect for many years,
and it seems no less pest to-day
than ever before, except as better
knowledge of its habits makes it
easier to ward off its injuries.
NATURAL HISTORY.
The wingless female moth, and
the trim male, with his ample wings,
both gray OF ash color, the female
being little the darker, come forth
from the ground early in the spring:
| have often seen the males during
warm winter days. DIR. Harris
states that these insects during open
winters come forth from October to
March, but usually commence about
the the middle of March, and con-
tinuc to issue from their earthen
retreats for about three weeks.
The female crawls up the trunks of
the apple and after meeting
the male lays her cluster of eggs
often to the number of one hundred.
If the female fails for any reason to
gain access to the tree she fastens
these egg clusters to any convenient
object. l have often seen them in
Cambridge, Massachusetts, fastened
to the pickets or boards of fences.
After egg-laying these insects soon
die. just as the leaves begin to
burst forth, the larvae begin to come
forth. The larvae vary very much
in color. At first they are very
dark, with faint ycllowish stripes.
When full-grown they are striped
with ash color, black, and yellow,
and are about one inch in length.
These larvae belong to the loopcrs,
or measuring worms, both names
referring to their peculiar method
of locomotion. They do not have
the usual number of legs for cater
pillars Q6), but must be content
with only ten. Hence their looping
gait. They are also called drop
worms, because of the habit ofswing-
ing from the tree by thread when
disturbed, or when they desire to
go to the ground to pupate. AS
they arc often seen thus suspended
it has been supposed that they fire.
quently swing just for the pleasure
of the thing. 1t may be that some
disturbing wind or bird induced
this strange manGuvre.
About the middle of June the
larvae are fed, the tree fully denuded
of its foliage, and that, too, at the
worst possible time, the growing
season, when thc"worms' make for
the ground, some creeping down the
trunk, others dropping down by
silken thread spun for the purpose.
Upon reaching the ground, they
burrow to the depth of four or five
inches, and in an earthcn cocoon
change to pupe. The chrysalis is
of a light brown color, and smaller
for male than for female.
This destructive insect is not con-
tent to injurc the apple-trcc alone,
but is equally ready to attack the
elm, and not infrequently attacks
cherry, plum, and other fruit and
forest trees.