Portable equipment for applying insecticidal concentrates by atomization


Material Information

Portable equipment for applying insecticidal concentrates by atomization
Physical Description:
Mixed Material
Potts, S. F ( Samuel Frederick ), b. 1900
Barber, G. W ( George W )
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 - 030345075
oclc - 781625940
System ID:

This item is only available as the following downloads:

Full Text

ET-144 M.-', y 193

United States Department of A-.riculture
Bureau of Entomology and Plant Quarantine


By. S. F. Potis, Division of Forest Insect Investigations, and
G. W, Barber, Division of Cereal and Forage Insect Investigations

Portable equipment for producing unusually fine spray atomi-
zation was needed by the writers in applying concentrated spray
mixtures and oils to small trees and to corn plants. Standard
equipment was not suitable, since the spray was not sufficiently
atomized and the nozzles often clogged.

Equipment was assembled which proved satisfactory for this
purpose. A 3/4-hp. gasoline engine, an air compressor, and an air
tank to avoid pressure pulsations were mounted on a flat metal base
10 inches wide and 28 inches lon., The metal base was then mounted
on a metal wheelbarrow chassis. Above the wheel a shelf was built,
to which a spray material tank of 2-gallon capacity was fastened.
The wheelbarrow chassis was so constructed that the engine-com-
pressor unit was parallel with the ground and was sufficiently low
so that the engine could be started with the foot crank. This
assembly is shown in figure 1. The equipment supplied a steady air
pressure of 60 pounds at the tank. The pressure at the nozzle was
about 50 pounds.

The nozzle consisted of a paint gun (fig. 2) and was con-
nected with the material tank by two 50-foot lengths of !-inch hose,
one conveying liquid and the other conveying air to the nozzle.
The paint-gun nozzle released liquid through an aperture 1 milli-
meter in diameter, while air was released through two apertures
each 7/8 millimeter in diameter. Atomization was accomplished by
the two streams of air intersecting the stream of liquid at a!.Ples
of about 45 degrees. The paint gun was handled directly when
insecticides were applied to corn, or was mounted on an extension
rod when insecticides were applied to trees (fig. 3). In the lat-
ter case a wire extending from the trigger of the gun to the bottom
of the extension rod served to release the spray.

The output of water by this nozzle was at the rate of 8
gallons per hour. This equipment was particularly suitable for
distributing lead arsenate concentrate consisting, of 1 part by
weight of lead arsenate, 5 parts of water, and 0.2 part of oil.


This was delivered at the rate of about 7 gallons per hour.
Concentrates containing as high as 1 part of lead arsenate to 1.2
parts of water were atomized successfully when a wetting agent was

Sprays delivered by this equipment consisted of very minute
droplets, and foliage could be covered with an inconspicuous ap-
plication of lead arsenate spray at the rate of from 1,000 to 1,200
droplets per square inch of surface. No plant injury resulted from
such applications. The efficiency of this equipment in delivering
spray when low growth is being treated is shown in the following

Number of men Pounds of Acres sprayed
Method of application to operate pressure per 8-hour day

Knapsack sprayer 1 50 1/8 to 1/4

Wheelbarrow sprayer 2 150 2/3 to 1-2
(hand operated)

Portable pressure equipment 2 50 6
(fig. 1)

To prevent clogging of the small aperture in the nozzle, any
trash or exceptionally coarse materials in the mixture should be
removed. This was accomplished by straining concentrates of lead
arsenate, calcium arsenate, or cryolite through a 60-mesh screen,
and concentrates of derris powder through a 40-mesh screen. The
lighter oils can be atomized successfully, but heavy oils must be
thinned (as with acetone) or applied as emulsions. Ordinary spray
mixtures can also be applied with this equipment.

The use of special equipment, such as described above, makes
possible the application of concentrated sprays, which have several
important advantages over ordinary sprays. A given volume of spray
material will cover a much greater leaf area or acreage because
much less water is used and because a larger proportion is actually
deposited on the plants. Because the quantity of liquid applied
per unit of leaf surface is small, there is no loss by run-off,
such as occurs with ordinary sprays. Less pumping and pressure and
less liquid and labor per acre are required. Time is saved in re-
filling the sprayer, and more rapid coverage of an area can there-
fore be obtained.

The method described has even greater advantages over dust-
ing. The initial deposit ranged from 2.3 to 7 times as great as for
dusting. After exposure to rain the adherence was much better than
in the case of dusts. None of the concentrated spray is blown off
the foliage, whereas air movement will remove a considerable por-
tion of the initial dust deposit. Winds of velocity up to 12 miles
per hour do not interfere with the application of concentrates, and
therefore spraying may be done during a larger proportion of the
available time.


Figure 1.--Wheelbarrow assembly of equipment for atomization
of sprays, showing wheelbarrow chassis, gasoline engine,
compressor, air tank, and material container.

"-. \

Digitized by the Internet Archive
in 2012 with funding from
University of Florida, George A. Smathers Libraries with support from LYRASIS and the Sloan Foundation


Figure 2.--Paint-gun nozzle.

Figure 3.--Nozzle attached to extension
rod, showing method of operation.


3 1262 08537 0830

Full Text
xml version 1.0 encoding UTF-8
REPORT xmlns http:www.fcla.edudlsmddaitss xmlns:xsi http:www.w3.org2001XMLSchema-instance xsi:schemaLocation http:www.fcla.edudlsmddaitssdaitssReport.xsd
INGEST IEID ELV98JEBP_K1L9RX INGEST_TIME 2014-04-21T23:03:09Z PACKAGE AA00017465_00001

xml version 1.0 encoding UTF-8
REPORT xmlns http:www.fcla.edudlsmddaitss xmlns:xsi http:www.w3.org2001XMLSchema-instance xsi:schemaLocation http:www.fcla.edudlsmddaitssdaitssReport.xsd
INGEST IEID EW3VCS413_1P7VUQ INGEST_TIME 2014-04-25T02:16:23Z PACKAGE AA00017465_00001