We have little black ants and bigger red harvester ants. The red ants are aggressive and will sting you. I ignore the little black ants but I don't want the red ants. I've used a product called Amdro on the red ants and it's pretty effective. You sprinkle some around the entrance to their colony and they all die. The colony doesn't come back for a long time, if ever. I wonder if it's just cornmeal (sure looks like cornmeal) with sugar??? It's pretty expensive.