Nests occur in loose soil and may be up to 60cm tall and 60cm wide and contain up to one-quarter million workers. They are a very aggressive species. Most ants are harmless. However, some ants may either bite or sting. Harvester ants have a blunt stinger but can produce a painful sting - usually they can't penetrate thick areas of skin, such as a hand.
Children generally are more likely to feel harvester ant stings than adults.
Fire ants produce a very painful sting which causes fiery itching, pustules, and sometimes more severe reaction including anaphylactic shock. An important step to any ant control program is to remove attractive food. Crumbs, grease, food scraps and other food is sought by foraging worker ants and they will return to areas where food is found. If ant-feeding bait is used as a control, it's important to remove other food so the ants concentrate on the bait and not the food. Most nuisance ants nest outdoors.