Atlanta semi-weekly journal. (Atlanta, Ga.) 1898-1920, 1918-09-13

great advantage of being much cheaper
than lead arsenate. These materials have
also been used in various strengths and
combinations. The work. of course, is
still in its experimental stage, but it is
! evident that the entomologists are on
the right track and that they will yet
be able to formulate methods of using
dust sprays which will be relatively
quite effective against the boil weevil
From what is known at the present
time il is apparent that di-hydrogen
lead arsenate containing not less than 81
per cent of arsenic pentoXid, or cal
cium arsenate containing at least AZ per
cent of arsenic pentoXid will produce an
effective control of the weevil if proper
ly handled and applied. No doubt these
materials can be diluted to a consider
able extent through the use of some
cheaper material such as lime. This,
however, has not hsNn definitely demon
strated as yet. IL is clear from what
has been accomplished up to the present
time that these materials should be APP
piled in the form of very fine powder.
1t has been found. for instance, that the
poison is more readily taken up and held
in suspension by dew or rain under such
conditions than when it is in relative
" coarse form. 1t is important to re
member, therefore, that the physical
COn0lTlOn
dust spray for the control of the weevil
is quite as important as the poison it
self
The time of spraying would, of course,
vary materially. As a rule it appears TO
be best to perform this work just when
the cotton Slackens in blooming. APP
parently the spraying should be done
about once a week in order to obtain the
best results. The most effective use Oh
the dust spray can, as a rule, be brought
about while the dew is on the plants.
This is due to the fact that the poison
not only clings to the plants better at
this time but there is much less ten
dency for it to drift away from the cot
ton. The best time for making the ap'
plication is between 4 O'Clock in the eve
ming and 9 o'clock in the morning.
Various machines are already on the
market which can be used for the appli-
cation of dust sprays. The implement
originally used was that known as a
dust gun. Where spraying is to be done
on an extensive scale, however, this
would be a costly and ineffective instru-
ment to use Therefore, special power
machines should be employed for this
work which would enable limited num-
Der of hands to cover say 200 or roo
acres I'm a day. 1t is hoped that types
OF machines Will SOOl NC NCNSAOpSN
which can be used by small farmers on
twenty or thirty acres of land a day.
They would be of moderate size ana
cost.
As TO the amount of poison needed,
definite conclusions have not been reach
ed. but apparently five pounds per acre
would answer. Undoubtedly this is an
excessive amount to use at present, but
it is not known definitely yet as TO what
would be best for the purpose of reduc-
ing the poison. In the experiments made
IN to the present time il is necessary
TO spray from three to five times.
The cost of treatment up to the pres
ent time has averaged about 81 per acre
for each application. Probably this can
be reduced considerably when better
types of spraying machines have been
developed and the method of application
worked out more definitely. If some ma
terial like lime can be used to, cut down
the amount of poison spray necessary,
the cost can be still further reduced.
This is the most powerful and con.
structive piece of work that has appar-
emily been done with reference to weevil
control up to the present time. 1t is too
early to say yet that it will afford =
definite means of fighting this pest eco
nOmically and successfully, but the out
look, to say the least, is very encourage
ing. These Investigations will, of
course. be continued and elaborated on
until the best method of procedure has
been worked out. 1t seems possible that
the date is not far distant when the
spraying Of cotton for the control of
the boil weevil may be done with a high
degree of efficiency and success and the
deprivations of this pest controlled with
as great a certainty and degree of st&-
cess as has attended the spraying Of
peaches and other fruit for the mitiga-
ton of damage done by various dis
eases and insects, such as the brown rot
and the curculio, which at one time
threatened to destroy our fruit industry.