Fire ants are endemic in much of the USA, especially south central. They thrive near electrical and magnetic fields and most people have a level of allergy to their bites. My first encounter resulted in a hand swelling to about double its normal size; I had no idea; the doctor looked around it and told me it was a fire ant bite. It took days to settle down.
The Americans have not been very successful in controlling them since most treatments, especially in individual consumer hands, merely do the equivalent of chasing them to the next lot, not eradicating the colony.
The basic problem is that it requires a community-wide effort not just ‘interested parties’. The approved treatment does not kill them, it sterilises the queen. Fire ant mounds are not atomic so missing any results in them rebuilding.
Many issues with the little pests, I have been bitten/stung several times and the bites/stings are unpleasant to say the least. I don’t think we have any hope of stopping their spread, all I think anyone can do is try to keep their yards relatively free of the pests by 3 monthly maintenance application of the bait.
There are a couple of pest treatments, the first being the baits but the final effective method is to use fipronil (used for termites as well) injected into the ground around the area of the nest usually at the mounds. Mounds are not the nest but are a way for the nest to control temperature, and allow ingress and egress to the nest for foraging and defense, mounds can be up to 30 metres away from the main nest. As fipronil is a class 2B pesticide/insecticide, frequent application will lead to resistance in surviving pests and it too can become ineffective as a treatment. Fipronil should only be applied/used by accredited and trained pest control experts, householders should not be applying the product themselves. Fipronil is dangerous to aquatic species, bees and household pets (including birds) and so proper care and application needs to be undertaken.
One problem with the bait is that if applied too often (more than the once per 3 months) the ants develop immunity to the product. Another is that if it is too hot when applied, the bait is too old (it becomes unpalatable to the ants as the oil used to carry the active ingredient becomes rancid), or it rains or is watered within 48 hours of application, the baiting is poor to useless in effect.
A photo from the Fire Ant Biosecurity site training course of some fire ant stings on an arm
As I understand it, they’ve spread well beyond the original point of arrival (Brisbane Part IIRC). I haven’t come across them yet, and I’m not looking forward to it. Apparently, they’re quite aggressive.
