UNITED STATES DEPARTMENT OF AGRICULTURE 
^OffitCTV 
In cooperation with the 
Air Service, United States Department of War 
DEPARTMENT BULLETIN No. 1204 
Washington, D. C. 
January, 1924 
DUSTING COTTON FROM AIRPLANES. 
By B. R. Coad. Entomologist, Bureau of Entomology, E. Johnson, Agricultural 
Engineer, Bureau of Public Roads, and G. L. McNeil, First Lieutenant, 
Twenty -Second Observation Squadron, U. S. Air Service. 1 
CONTENTS. 
Page. 
First use of airplanes in applying 
insecticides 1 
Dust hopper construction 2 
The hand-crank hopper 3 
The air-suction hopper 5 
The Dayton hopper 7 
Field dusting studies 9 
Location and plan 9 
Leafworm conditions 12 
Behavior of the dust in the air_ 12 
Influence of various air condi- 
tions 18 
Adhesion of poison to plants 21 
Manipulation of planes 21 
Flying methods used 22 
Rate of dust delivery 26 
Directing plane operation 29 
Leafworm control operations __ 29 
Field dusting studies — Continued. Page. 
Tests of various insecticides 31 
Different calcium arsenates- 31 
Lead arsenate 32 
Paris green 32 
Observations on boll weevil con- 
trol 33 
General considerations of airplane 
dusting 33 
Acreage dusted per hour 34 
Advantage of airplanes after 
rainfall 34 
Suitability of terrain 35 
Control of dust spread 36 
Suggestions for future investi- 
gations 37 
Characteristics of airplanes used 38 
Cost of operation 39 
Conclusions 40 
FIRST USE OF AIRPLANES IN APPLYING INSECTICIDES. 
The possibility of applying insecticides by means of airplanes was 
first brought to public attention by the work conducted in August, 
1921, by the State Experiment Station of Ohio, in cooperation with 
the United States Air Service, near Dayton, Ohio. 2 This particular 
test consisted of distributing lead arsenate from an airplane over a 
grove of catalpa trees in an effort to poison the larvse of the catalpa 
sphinx (Ceratomia catalpae Bdv.), which were defoliating the grove. 
The experiment proved quite successful and immediately suggested 
the possibility of using the airplane for the control of other insect 
pests. Especial interest was aroused in the possibility of using the 
airplane to combat the cotton boll weevil (Anthonomus grandas 
Boh.), and plans were made for such experiments to be conducted 
1 In conducting the experiments described in this bulletin the writers were assisted by 
a number of men from the Delta Laboratory force at Tallulah. La. They are particu- 
larly indebted to the following: A. J. Chapman. R. II. Flake. S. P.. Bendricks, R. I.. 
Hodges. I. T. Jones. II. Kirkpatrick, P. D. Sanders. C. M. Smith, and M. T. Young. 
2 Fighting Insects with Airplanes. Neillie, C R., and Houser, J. L. In Nat. Geog. 
Mag., vol. 41, no. 3, pp. 232-238, March, 1922. 
61979°— 24- 
