My buddy from Atlanta Georgia swears this works.

Go to Home Depot or Walmart and buy a can of black spray paint.

Stir up each ant mound as you go and the area around them with a stick. The ants will emerge by the hundreds to defend the mounds.

Spray each mound and the surrounding area, making sure you get plenty of paint on the ants as well.

Once the ants realize they live in a black neighborhood, they quit working and start killing each other.