Bismarck daily tribune. [volume] (Bismarck, Dakota [N.D.]) 1881-1916, 1901-04-24
THE CANKER WORM.

III CANKER WORM.
HOW TO DISTINGUISH THE PEST
AND THE PROPER REMEDY FOR
Relief THEREFROM.
a In most sections of the state last
year there was great devastation
among the forest trees and also orna-s
mental trees of door yards and streets.
owing to the presence in very large
numbers of the larvae of the canker
worm. This is an old offender in the
eastern states, though we have no
record of it's having committed such
serious damage in North Dakota IN
til the past season. In the oldest
states it's damage is more noticeable
in orchards and particularly in apple
orchards. Its ravages on forest trees
have not been such as to attract gen
eral attention. While the destruction
which this pest in large numbers is
capable of doing is very great. yet ow-
ing to certain peculiarities of it's life
history and structure, the means of
combating it are rather simple and
do not entail any great amount of
time and expense. The canker worm
IN it's larvel stage is readily distin-
| guished by it's peculiar habit OF loco
motion. 1t is sometimes called the
measuring worm or he loop worm,
both of which names give an idea Of
its method of travel, that is by plac-
ing down the legs at the forward end
o. the body and looping the body up
in such a position that the hind legs
are brought Immediately back of the
fore legs. With the hind legs held
fast, the front Of the body is then
lifted and stretched to the full
length of the worm, where it is again
placed down in readiness for another
step. The larvae also have a peculiar
habit of swinging down from the
limbs whenever they are disturbed,
remaining suspended on a fine silken
thread, which they spin out as they
fall. Afterwards they climb back up
the thread at their leisure. This pc
e1,liar habit affords them protection
from birds. It rlso enables them to
pass through from one tree to another
in search of new food, for when sus-
pended in mid air, the wind readily
blows them to any adjoining tree.
The full-grown caterpillers are an
inch and a fourth to III inch and a
half in length and vary from a green
to an indefinite brown, with rather
vague longitudinal stripes. The eggs
from which these: caterpillers hatch
are usually deposited upon the twigs
Ct the trees in the months of April or
May, though it sometimes happens
that a few OF. the insects develop from
the spring larvae late in the summer
and lay their eggs in the fall.
The moth of which the canker worm
is the larvae is rather peculiar in that
the female is wingless. On account
of this they. are Obliged to climb the
trees in order to deposit their eggs.
It is owing to this peculiar habit that
we + able to prevent their devasta-
tions. By putting some mechanical
continuance around, the body of the
tree early in April, the females are
prevented from depositing their eggs
in a place where the young can do any
injury. A strip Of tarred paper put
around the tree and fastened tightly
with a wire or cord near the upper
edge, allowing the lower edge to fare
out from the trees makes; a. very good
protection. It is made still better by
smearing the inside Of it, with cheap
molasses or a mixture of tar and grease
melted together. Tin collars are
sometimes made with a lower laring
edge, that answers the purposes admir-
ably. They can be attached to the
tree by lacking one end and passing
the other end around SO as to join it,
when another tack can be inserted. If
the bark is rough it will be necessary
to put felt on some other such material
between the collar and the tree to pre-
vent the moths climbing up in the crew
ices Of the bark. It is also sufficient
simply to ,snea the trunks with a mar
row band Of tar and grease OF with
cheap molasses, # this material
hardens a new application must be
made. Cotton or wool is sometimes
tied about the tree. This answers the
purpose if it does not become matted
together. Of course it is useless to
put ia any Of these c~ontrivances after
the moths have passed up the tree,
which in this latitude In ordinary
years would be about the first of May.
4 S GfgL M E&E 81 ~ EA4 rL.E W. IENEGI