A small field duster


Material Information

A small field duster
Physical Description:
Johnson, George V ( George Victor ), 1910-
United States -- Bureau of Entomology and Plant Quarantine
U.S. Department of Agriculture, Bureau of Entomology and Plant Quarantine (Washington, D.C )
Publication Date:

Record Information

Rights Management:
All applicable rights reserved by the source institution and holding location.
Resource Identifier:
aleph - 30361382
oclc - 783264718
System ID:

Full Text

July 1948 ZT-259

United States Department of Agriculture
Agricultural Research Administration
Bureau of 3ntomology and Plant Quarantine


George V. Johnson,
j Division of Truck Crop and Garden Insect Investigations

A duster was constructed for treating individual tomato plants in
field plots at Columbus, Ohio, in connection with experiments for the
control of the tomato fruitworm (Heliothis a (Hbn.)). Weighed
quantities of dust ranging from 2 to 7 gn, were used in the duster de-
scribed here.


A cutaway diagram of the ouster is shown in figure 1. The dust
chamber (A) was formed from the bulb part of a 50-ml, pipette. The
constricted top part of the bulb was cut off. About an inch of the bottom
stem was retained. and was bent and shaped to form a dust-discharge ori-
fice QL) approximately 0.08 inch in diameter. The air tube (j) was made
from a 7-inch length of 1/8-inch copper tubing. The outlet (D) of this
tube was constricted to approximately 0.08 inch by sealing the end with
solder and boring a hole through the seal.

The dust chamber and the air tube were placed in a protective hous-
ing made from a cylindrical piece of wood about 21 inches in diameter and
6 inches long. A hole to fit the dust chamber was bored into the cylinder
deep enough to sink the top of the dust chamber %bout 3/4 inch below the
top of the wood cylinder. The top 3/4 inch of the cylinder was cut to
make a funnel-shaped opening. The bottom was hollowed out roughly as in-
dicated. A 3/16-inch hole for the air tube was bored in the wood cylinder
so as to bring the air tube into proper alignment with the dust-discharge
orifice We

The dust chamber was fastened in place with plastic cement around
the top and bottom. The position of the tip of the air tube (D) to give
the best dusting action was determined by trial. The air tube was fas-
tewed in place with plastic cement.


A 2-cylinder air compressor of the paint-sprayer type powered by a
small gasoline engine, supplied the air for dusting. An air line with a
cut-off valve connected the compressor with the air tube of the duster. A
weighed quantity of dust was placed in the dust chamber. When the air was


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turned on, the air stream across the tip of the dust chamber delivered the
dust from the chamber. This duster has been operated with the compressor
set at pressures of 10 to 17 p~mnds per square inch.

Figure l.--Cutaway diagram of duster.