I don't know about the corn thingy...but we were told to use diatomaceous earth...and it did not work. We ended up using a special fire ant poison. We are not big fans of poison...but after being bitten once of twice by fire ants...we have taken the risk.
It may have a similar affect that grits do. When the ants eat grits, it is suppose to expand in their tiny little stomach and rupture them from the inside out.
I've used grits and it does have an affect, not nearly like poison, you can definately tell that the grits have worked because there will be dead ants lying around the next few days. Although, the grits won't take out a whole mound, just those that eat it..
There are numerous home remedies for fire ants i.e. cornmeal, grits, Dawn dish detergent, Tide laundry detergent. Problem is; the fire ants don't know that. They just keep on keeping on. In answer to your question, no, cornmeal will not kill fireants. The theory behind that was that they would eat it then swell up and die. Millions of dollars have been spent in studying how to erradicate fire ants by the universities. Every time a control agent "that works" is put on the market, it gets banned.
Fireants are here to stay and your best effort won't be enough to totally get rid of them. I read a recent article that they are now working to develop a viral infection to apply to them and kill the mound. That will be interesting.
20 mule team borax works on all insects! It is actually an enzyme that boosts the cleaning power of laundry soap, but also increases the metabolism of insects so that they "burn out". It works for fleas, spiders, ants and all kinds of other bugs, but doesn't do anything to warm blooded creatures. It is also very cheap and easy to find, and is not "poison" to us or animals! The insects take it back to the nest, die, get eaten, then it works on the others in the nest. Enzymes are great cuz they keep working!
Neem oil also works, but is expensive and stinks really bad. I use it for ticks and fleas on my dogs, also for mange, both sarcoptic and demodectic (neighbor's dog, not mine!)Both are organic, and work well. No documented incidences of resistance. No known side effects, except for the nasty smell. I think it might work on mites..........have to look it up for chickens.
Thanks folks for the input. I figured that was a bunch of hooey!! Might try the Borax though. The fire ants here are plentiful, to say the least, and we try to control them as best we can. Will chickens eat them?
As an aside, I used 100% Neem oil mixed with baby oil on a goat that I had who had mange around her neck and it got rid of it.
*I don't think neem smells that bad- it's a kinda burnt onion/garlic smell. BUT NEEM'S killing action is unique and EXTREMELY dangerous to BENEFICIAL insects. I ONLY use indoors and/or internally for that reason.
DE (diatomaceous earth) does work. It does kill some of the mound but the mound will just relocate. Thats one reason fire ant are so succesful. At the first sign of "attack" they just pick up and move. Amdro is by far the best commercial product available to the public. You'll never get rid of every ant, but Amdro sure keeps them manageable.