Atlanta tri-weekly journal. [volume] (Atlanta, Ga.) 1920-19??, 1923-12-27
A|RPLANE BUSTING
To KILL WEEV|LS
FOUND EFFECTIVE

WASHINGTON, Dec. 24.-Air'
plane attacks on the boil weevH
most destructive enemy of the cot
ton crop, have proved successful and
calcium arsenate dust has been
found the most effective poison for
&the weevil and other cotton insects
the department of agriculture an
nounced today after extensive eXper-
iinents.
More tests are needed to develop
better designs of planes and equip
ment and to improve methods, anu
experimental work is being contin'
ned as available funds permit.
Though calcium arsenate is declared
by the department to be the best
poison known at the present time
for the weevil, other poisons also
are being tested.
B. r. Coad, of the bureau of ento'
mology, in charge of the cotton in
sect Investigations at the govern
ment station at Tallulah, La, dur
ing the last few years, has made ex
tensive tests of poisons and ways
of applying them. 1t has been
shown that busting with calcium ar
senate will make possible a profitable
increase in yield of seed cotton eX'
cept where the land is Of low pro
ductivity. Fields busted with cal
cium arsenate by airplane this year
showed an increase of $50 pounds
per acre of seed cotton over those
>on adjacent plantations that were
not poisoned. ~
Plane Use Costs Little
Although the cost of busting with
airplanes, which were supplied ana
manned by the air service OF the
army, is not definitely known, it is
estimated to be about So per acre.
AT present prices of cotton the gain
from busting was over SIS an acre.
1t is thought the cost of busting by
airplane is less than with ground
machines.
, The tests at Tallulah are designed
to bring out information of many
phases of the problem of cotton in
sect control. During last summer
the treatment covered approximately
5000 acres, on one plantation the
fields being unobstructed by build
ings and trees and on the other
broken up by woods, barns and cab
ms. Both Of the plantations We're
heavily infested with the boll-weevh
and the cotton leaf worm. In addl-
ton to the airplane busting much
cotton was treated with other pol-
sons and with various machines and
methods of treatment. Trials are
being made in using the airplane in
distributing piosons for the control
OF other crop pests. such as the
= alfalfa weevil, the potato beetle, ana
various orchard insects.
The experimental work in apply
ing calcium arsenate dust by means
Of airplane developed some impor-
tant fundamental facts concerning
the application of dust. When dust
ing was first practiced it was found
necessary to work at night when the
moisture on the plans would cause
the dust particles to stick. Dust ap-
piled by airplane in the daytime,
however. was found to stick and a
pound Of material went farther than
when applied by other means. Elk
Fperimenters believe the better effect
is gained because the particles Of
the powder are highly charged with
positive electricity while the plants
carry a negative charge.
Speed Charges Particles
The charge of electricity is
thought to be produced by the fric-
tion Of the plane with the air and
by the friction of the dust particles
with the air current which has a
speed of 125 to 1875 miles an hour.
Scientists are trying to produce
this same sticking quality in dust
applied by other machines. Mr..
Coad says if all the particles could
be separated a pound of calcium ar
senate would be sufficient to effec-
lively cover an acre of cotton.
Ground machines are being equipped
with high-frequency and fight-volt-
age generators to determine il the
dust can be charged in this way.
The first suggestion of the charged
dust explanation was obtained when
it was noticed that fog was precipi-
tated when a plane shed dust on it
from above.
Development of airplanes espe-
eial1y adapted to busting may re-
suit in better and more economical
results, it is said, and certain man.
ufacturers of planes are taking an
interest in the problems.
Planes used last summer were
equipped with 420-horse power Lib
erty motors, but their design was
Such that only $50 pounds Of calci-
UNI arsenate could be carried,
enough for only about minutes of
busting. BY using the same motor
and changing the design it is
thought it may be possible to carry
1000 pounds at load.
The busting with calcium arsenate
is effective not only in reducing the
damage done by the boil weevil, but
it also controls miscellaneous cot
ton insects, including grass hoppers,
.caterpillars and worms, but not lice
and other sucking insects and not
the pink boil worm which works in
ciAA Tho hall