Hi Ralf, We have used (near) boiling water to douse the nest – repeated several times. Just be careful around boiling water. You can also just run over the rest repeatedly with a riding mower or lawn mower until the ants give up and move. One recommended treatment is Spinosad Landscape and Garden Insecticide, an organic pesticide judged safe to use on ornamental plants, as well as in fruit and vegetable gardens. The maker, Natural Guard, reports that it’s also relatively safe to use around beneficial insects.
Hi Ralf, We have used (near) boiling water to douse the nest – repeated several times. Just be careful around boiling water. You can also just run over the rest repeatedly with a riding mower or lawn mower until the ants give up and move. One recommended treatment is Spinosad Landscape and Garden Insecticide, an organic pesticide judged safe to use on ornamental plants, as well as in fruit and vegetable gardens. The maker, Natural Guard, reports that it’s also relatively safe to use around beneficial insects.
We hope this helps. Here is more information from your NC State cooperative expension on fire ants: https://content.ces.ncsu.edu/red-imported-fire-ant-in-north-carolina and also Bahia Grass: https://content.ces.ncsu.edu/bahiagrass. They are your best source for on-the-ground advice.