Ants & imported fire ants

Ants are recognized by their elbowed antennae, narrow waist, and characteristic mounds of loose, excavated soil pushed up onto the turf surface. The red imported fire ant builds distinctive dome-shaped earthen mounds and delivers a painful, burning sting; workers swarm aggressively when the mound is disturbed. Most turf-nuisance ants are noticed by their soil mounds and foraging trails rather than by direct turf injury.

Unsightly soil mounds that dull mower blades, smother grass, and disrupt playing and mowing surfaces; fire ant mounds also pose a stinging hazard to people and pets. Direct feeding injury to turf is usually minor — the nuisance is the displaced soil and the sting risk.

Ants are social insects with complete metamorphosis living in colonies of a queen (or multiple queens), workers, and seasonal winged reproductives that disperse in mating flights. Imported fire ant colonies can contain tens of thousands of workers and persist for years; colonies expand fastest in warm weather and relocate or rebuild mounds after disturbance or rain. Most species overwinter as established colonies deep in the soil.

Mound activity peaks in spring and fall and after rain when soil is workable, and is most problematic in warm-season turf of the southern U.S. for imported fire ants. Mounds concentrate in sunny, open turf; colonies readily move and multiply, so untreated areas are continually re-infested from surrounding sources.