In article , wrote:

I was wondering if anyone tried those high-frequency sonic plug-in
devices to ward off plant-eating pests? I grow plants under
fluorescent lights and I'm wondering if these sonic devices would help
with mealy bugs, aphids, scale, etc? Are these devices a hoax?

This devices are completely phony. Here's my article on the topic, with
citations:

http://www.paghat.com/ultrasonic.html

-paghat the ratgirl
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"In every country and in every age, the priest has been hostile to
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