Pullman herald. [volume] (Pullman, W.T. [Wash.]) 1888-1989, 1905-06-10
THE COOLING MOTH.
A 100000 Worm that is Now Being
Investigated by the Washington
State College.

The department of Biology is MAX
ing rapid and satisfactory progress
In its work on the Cooling moth. To
most people it is known that this
moth is the greatest pest apple raisers
have to contend with. It is estimated
that over 100000 was lost to the
fruit growers of the Inland Empire
last year because of the ravages of
this insect. 1t was introduced into
the Walla Walla valley about rs years
ago from Oregon and is now found
all over the state and is spreading
rapidly. In most of the warmer river
valleys the apple crop, unless con-
stantly sprayed, is now an entire fail
ure.
The moth is a small, insignificant
looking affair. Two broods year
are produced. The worm of the
first brood matches from tiny egg
laid by the moth on or near the young
apple about two weeks after the trees
have blossomed. 1t Immediately en-
tiers the flower end of the apple, where
it lives and grows for from two to four
weeks. Becoming full grown it des-
cends to the ground, spins silken
cocoon about itself and 'pupates. "
In little over two weeks it is trans
formed into moth, which lays eggs
on the apple and the life histoy is re-
peated.
The work of the department
of Biology is the most elaborate and
best conducted line of experiments yet
undertaken with the moth. 1t was
begun three years ago under the di-
rection of Prof. Piper. Since then
work has progressed steadily and con-
tinuously. Two members of the de-
apartment, Eldred Jenne and Ernest
MacKay, are now in the Yakima val
ley carrying on the work there, under
the direction of Prof. Melander.
Two great problems confront the sci
entists; how to destroy the moth and
. how to do it in the most effective and
economical way. In order to obtain
the desired results, the life history
of the moth must be studied over sew
eral years time. A vast amout of
data has been collected and carefully
arranged. Jenne traced the life his
tory of the insect in the summer of
1903. 1t is necessary to understand
the time of the changes in the insect
in each particular region in order to
determine the proper times for spray
ing. 1t has been found that an early
or late spring makes difference of
two weeks or month in the life
events of the insect. A difference of
a fourth of a degree of latitude
causes a days difference in time.
A hundred feet in altitude has the
same effect. The life history in every
locality, therefore, must be studied.
No date of the calendar can be set as
a time for spraying on account of
seasonal variations, latitude and alti-
tude. The scientists are overcom-
ing this difficulty by noting the stages
of various flowers and fruits at i'm
portant times in the insects history.
When the work is completed infor-
nation will be given, not to spray at
such and such time, but to spray
when certain plant is in bloom or
in fruit.
Already much has been accomp-
lished in determining the values of
different kinds of spray poisons.
The values also of dust and LIQUID
sprays are the subject of experiment.
Thirty-fve methods of spraying are
being tried. It has been found that
under normal conditions five spray
ings a season are as efficient as any,
greater number. The work done is
o1roodv of immense Ualuo RI fy11it