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Is Untrasonic Electronic Pest Control, Effective?
tedgyz asks: "I have declared war on the pests in my house. I am tired of hearing the scurrying of mice and squirrels in my walls. Worse - I am tired of the nests littered with droppings buried in boxes in the attic. I have used standard traps, and although successful, it seems that new rodents or more than happy to replace the ones I've killed. Are ultrasonic deterrents effective?"
"I've searched the web, but I can only find marketing material from manufacturers and distributors. I'm looking for cold, hard facts.
- Do ultrasonic deterrents really keep rodents out of your house?
- What is the range?
- Do they last, or do the rodents eventually return?
- Are they truly innocuous to dogs and cats?
- How do you measure success?"
They do work in certain cases -- I have two in my house (kitchen and computer room), and they have stopped my mouse problem.
Rooms with odd geometry or many sound-absorbing obstructions don't work very well. A good rule of thumb is that these will only protect areas an IR remote would reach from the outlet they're plugged into -- in other words, line-of-sight.
One word of advice -- don't go cheap! The cheap ones audibly click, and give sensitive people headaches. The good ones are unnoticable to pets and humans.
As for range, it varies -- but usually only one room per device. See labeling!
We may not imagine how our lives could be more frustrating and complex—but Congress can. – Cullen Hightower
It's a known fact that some animals (especially smaller ones) can hear a much wider frequency range than humans can.
"genetically similar" means nothing - A few kilohertz can make a lot of difference.
But one has to be careful not to get TOO close to the human hearing range, as within 3-4 kHz of the human hearing range, it causes US discomfort. A bit above that and it won't cause pain for humans at all, but will sound like an unholy shriek to a small animal.
Note: I'm talking about the ultrasonic-only ones. And having multiple small units scattered around is probably better for our ears than one large super-loud unit, as one superloud unit might still have enough SPL to damage someone's ears even though we can't hear it. (Although it helps that the ear won't have any resonances at those frequencies - This is why smaller animals can hear higher freqs, smaller ear canals = higher resonant freqs.)
retrorocket.o not found, launch anyway?
Surprisingly, Chrysantemum seeds work against roaches. We set some out a while back and the roaches dissapeared.
Not so surprising; chrysanthemums contain pyrethrins, a natural insecticide.
No, they don't work on insects (at least, nobody has been able to get them to work in independant testing labs). Apparently, this is due to the fact that mosquitoes are nearly deaf.
You can buy expensive CO2 generator/electrostatic killers; they work to a certain extent. By that I mean they attract mosquitoes, they kill mosquitoes, but they don't kill as many as they attract. Net result: more mosquitoes than you had before.
You can buy bug zappers. They work as well, but apparently there are serious health hazards associated with haveing microscopic bits of blown up insects landing in your food. "Zapper" is an interesting description; but the correct term is more like "vaporizing".
You can use Citronella candles, and citronella bug sprays. They work, but not so well; some lose effectiveness after as little as 15 minutes, some as long as 2 hours.
You can use Avon Skin-so-soft, which works for 15 minutes. Apparently mosquitoes hate slick skin creams of all kinds, so plain-jane lotions work as well and as long.
DEET is the only thing that actually deals with flying insects over a decent period of time. Currently the recommendation is to use no stronger than 30% DEET formulas.
Other, "envoiornmentally friendly" spray/apply lotions work, but for short periods of time. Since most should not be used more than twice a day, that doesn't help if you're really outdoors.
Mosquito coils work because they contain a pesticide. You decide if that's what you want your kids breathing.
Bug jackets work; remember that if the screen touches your skin they can bit through it.
What really works is getting rid of the breeding sites. A single coke can with an inch of rainwater can grow about ten thousand mosquitoes; you have your work cut out for you, but it does make a real difference. If you have a pond, put fish in it. They eat the larvae.
There are about 90 kinds of North American mosquitoes, and they have specific habitat preferences. Thus, in the rain, you get the kind that like humidity and lower temps. At evening, you get the kind that like the sun going down and the temps falling a bit. So, chances are that the kind that give you the reaction will either die off sometime during the season, or you're having consistent weather they like, but getting at the breeding sites is your true best option.
You may well be having an allergic reaction of some kind as well; since allergies are cumulative (ie the reaction doesn't happen until you get some personally significant number of bites, a threshold you may have exceeded). I would use DEET but it's up to you.