Although not as harmful to turf as worm casts, ant hills can disfigure lawns and are more common where the soil is sandy. They usually appear in summer and should be dispersed by brushing the soil when dry. This will avoid smearing them on the lawn when mowing, which over time will lead to the lawn becoming uneven. Ants can also damage roots which may cause yellowing.
Ants can be controlled by treating with a biological nematode. The nematodes act as an irritant and the ants are displaced from their colonies. Lawns can be treated from April to October when the soil temperatures are warm enough for the nematodes to be effective. Where ant levels are very high repeat applications may be required to prevent the ants returning to the colony.