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JOURNAL OF ECONOMIC ENTOMOLOGY 
[Vol. 16 
and the second pertained to the dusting of a four acre catalpa grove 
near Casstown, Ohio, moderately infested with the catalpa sphinx. 
As in the work of 1921, that of the present season was done in co¬ 
operation with the United States Aviation Experimental Station at 
McCook Field, Dayton, Ohio, and it is a pleasure to again recognize the 
efficient, painstaking effort of all of the men of the Field who were in 
any way connected with the project. We were fortunate to again 
have the services of Lieut. J. A. Macready as pilot for the Cleveland 
test and of Mr. M. Dormoy to operate the hopper in both of the tests. 
In the absence of Lieut. Macready, Lieut. Moseley piloted the dusting 
plane for the Casstown test. 
The same hopper for carrying and distributing the poison was used 
this year as last and the plane was of the same type, a Curtiss JN-6. 
In both tests this season a second plane accompanied the dusting plane 
for observation and photographic purposes. 
The powder used was an undiluted, finely ground, flocculent type of 
arsenate of lead, which, according to our present standards, sticks 
fairly well in the dry form to foliage. However, there still remains 
considerable room for improvement of the adherent properties of the 
material and it would seem that researches having for their object the 
improvement of this property of the poison are much to be desired. 
Some trouble was experienced with the powder compacting in the hopper, 
particularly if the plane flew several miles through “bumpy” air after 
the hopper was filled. This, however, is a mechanical defect which 
could be overcome quite easily through the installation of a simple 
agitator. 
The Cleveland Test 
The woodland in which this work was done was a part of the J. L. 
Severance estate and is located some twelve to fifteen miles east of the 
center of Cleveland. It is almost square in shape with but slight topo¬ 
graphical variations and covered approximately thirty acres. The 
trees were irregular both in size and spacing, varying in height from 20 
to 65 feet. In some parts of the woods the stand was very thin while in 
others the taller trees were close together and beneath them was a 
dense growth of underbrush and low-growing shrubbery. 
The native tree fauna of northern Ohio was fairly well represented in 
the plot, the predominating species being beech. Others represented 
were hard and soft maple, American elm, basswood, oaks of various 
species, ironwood, etc. The native undergrowth had been supplemented 
