I quickly left the area and brushed all the ants off my legs and feet with sticks. They were not biting me, just walking on me. Luckily I was wearing long pants. I went home and returned later after doing some online ant research with backup - Randy came with me to see the fire ants. And this time I brought my camera.
The ants were all over some leaves in the woods and they were walking on an old piece of metal. This is in an area where several pieces of metal were dumped many years ago. Randy is going to pull all this metal up out of the ground and take it to a metal facility where he will get paid for it.
The ants were everywhere, and they all were working. They were all carrying sticks and leaves and things, and they all were heading underneath this piece of metal. I assumed at this time that the crunching sound was caused by so many hundreds of thousands of ants walking on crisp leaves. Randy, being the man that he is, just had to pull up the metal to see what was underneath.
And it was a horrible sight. There were millions of fire ants. The crunching sound was super loud now. Maybe the crunching was caused by the irritated ants moving their horrible pinchers? All the red/brown color in the below photos is ants. It is not dirt. The ants went crazy when Randy moved the metal covering their home. They started swarming, and we quickly had to run away, as they started climbing up our legs and were biting and stinging our shoes and pants in a frenzy.
Here's some information from Wikipedia on fire ants:
A typical fire ant colony produces large mounds in open areas, and feeds mostly on young plants, seeds, and crickets. Fire ants often attack small animals and can kill them. Unlike many other ants, which bite and then spray acid on the wound, fire ants bite only to get a grip and then sting (from the abdomen) and inject a toxic alkaloid venom called solenopsin, a compound from the class of piperidines. For humans, this is a painful sting, a sensation similar to what one feels when burned by fire -hence the name fire ant - and the after effects of the sting can be deadly to sensitive individuals. The venom is both insecticidal and antibiotic.
Fire ants nest in the soil. Usually the nest will not be visible as it will be built under objects such as timber, logs, rocks, pavers, bricks, etc. If there is no cover for nesting, dome-shaped mounds will be constructed, but this is usually only found in open spaces such as fields, parks and lawns. These mounds can reach heights of 40 cm (15.7 in). The mounds that the fire ants live in can also be as deep as five feet.
Colonies are founded by small groups of queens or single queens. Even if only one queen survives, within a month or so the colony can expand to thousands of individuals. Some colonies may have multiple queens per nest.