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PEST CONTROL BY PHYSICAL MEANS 
Ronald Paugh, Senior Illuminating Engineer, General Electric Company, 
Nela Park, Cleveland, Ohio 
Physical methods of insect control bring 
instantly to mind such devices as the fly- 
swatter or flypaper. But, in this case, a more 
sophisticated approach to this problem is in- 
tended. Here, the word "physical" refers to 
the luring of, the entrapment of, and the dis- 
position of the insect pest by mechanical 
means, 
The method of luring these insects is of 
primary importance, since the success or 
failure of the device is determined by the 
number of insects enticed into the device. 
Attractants of all types have been used, All 
have one characteristic in common, that of 
catching insects by capitalizing on their nat- 
ural inborn senses. Historically, insect traps 
designed on this basis were used as early as 
the mid-1800's. True, these traps were simple 
devices, but they took advantage of specific 
insect habits. For instance, since the codling 
moth spins its cocoon in protected places on 
trees, Joseph Burrelle in 1864 suggested wind- 
ing something around the trunks of apple trees 
or placing a cloth in the crotch and then des- 
troying the trapped codling moth larvae by 
disposing of the cloth and winding material. 
Such traps and their modern successors have 
proven themselves useful tools in today's re- 
search as measurement devices. Recent stud- 
ies indicate that insect traps, employing 
sources of electromagnetic energy as the 
attractant, may be used as effective devices 
for control, as well as measurement, of 
certain night-flying insects. 
The following papers present an excellent 
cross section of present research in the use 
of insect traps for insect control: P, C, Calla- 
han presents information, data, and theories 
in his paper, "Electromagnetic Communication 
in Insects,'' concluding that various species of 
moths may have communication devices that 
depend on the detection of energy in the far- 
infrared region of the electromagnetic spec- 
trum. He indicates that such sensitivities 
might be used to advantage in control devices. 
S. O. Nelson and J, L. Seubert provide an ex- 
cellent resumé of past and present research 
and its possible direction in the future in 
"Electromagnetic Energy and Sound for Use 
in Control of Certain Pests.'' F, R, Lawson, 
C, R. Gentry, and J. M. Stanley present the 
encouraging results of their tests involving 
the control of the tobacco hornworm with light 
traps in their paper, ''Experiments on the Con- 
trol of Insect Populations With Light Traps." 
To complete the picture, W. M, Carleton and 
R. D, Brazee point out the part the agricultural 
engineer can take in the studies on physical 
control of insects in the ''Role of Agricultural 
Engineers in Pest Control." 
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