Dealing With Biting Ants in Lawns

Controlling biting ants in customers’ lawns is an excellent add-on service for pest managers.

For most homeowners and businesses, dealing with ants inside the home or building is often the main problem. However, outdoor ants, especially biting ants in the lawn can still be an issue for homeowners, businesses and organisations wanting to protect their children, pets and customers from harm. Customers may not always contact pest control companies to deal with this issue, and sometimes they may not even be aware they have a problem, but it is a great up-selling opportunity or add-on service. With products like Synergy Pro from Sumitomo, pest managers have the tools to deal with biting ants in lawns with confidence. Let’s have a look at the main biting ants that are found in lawns in Australia.

Perhaps the most common biting ant in lawns is the native green-head ant, Rhytidoponera metallica (pictured above). They will readily sting, especially if their nest is disturbed. Although their sting can be painful (but not as bad as a bee sting), the main issue to be aware of is potential anaphylactic shock. However, for most victims it’s the persisting itching at the bite site that can last for a week or two that’s the most annoying. They readily build their nests in lawns and will often have two or three nearby nests as part of the same colony. Neighbouring colonies will set up home nearby, so their density in infested areas can be significant. It can make lawns and playing fields somewhat unusable, especially if barefoot!

Another common native ant, or rather group of ants, are the tyrant ants (also called rainbow ants). Tyrant ant is the common name given to Iridomyrmex species, although the larger tyrant ants are typically called meat ants. The various species of tyrant ants are found across Australia and will typically nest in open areas, including gardens and lawns, developing nests of up to 100,000 or more individuals. The many different species vary in size and colour, but are predominantly black or brown. They are fast moving, aggressive ants and will feed on sugary honeydew as well as scavenge for insect prey. They can exist in large numbers in lawns and trailing up plants. Although they have no sting, they will readily bite. It may not be particularly painful, but it is certainly enough to cause annoyance when sitting on the grass.


Black ant with red mouthparts
One of the common tyrant ants, Iridomyrmex bicknelli (photo credit: Alex Wild)


Two invasive ants are becoming a serious problem in Australia, particularly in Queensland – the yellow crazy ant, Anoplolepis gracilipes and the red imported fire ant, Solenopsis invicta. Both are readily identifiable, have the ability to form ‘super colonies’ and tend to dominate areas once they become established.


red imported fire ant worker
Red fire ant, Solenopsis invicta


The yellow crazy ant is common in the Northern Territory and tropical north Queensland, and has now spread as far south as Brisbane and northern NSW. It is a golden brown, fast-moving ant about 5 mm in length, with long legs and antennae. It often moves in an erratic (‘crazy’) manner. Although it does not sting, it does spray formic acid that irritates skin and eyes. They have mobile colonies and will build their nests in leaf litter, gardens and in houses. Like the tyrant ants, they will feed on nectar and honeydew, as well as animals (both dead and alive!). They extend their nests through budding to form super colonies.


The yellow crazy ant, Anoplolepis gracilipes, is no longer considered eradicable


The red imported fire ant continues to spread in southeast Queensland and is now just north of the NSW border. A small brown/red ant with workers varying in size from 2-6 mm, it forms nests with loose mounds of earth, from which the ants ‘pour’ when disturbed. They have a painful bite (like a bee sting) that can cause severe allergic reactions and anaphylactic shock.

All these outdoor biting ants can be dealt with using Synergy Pro or Distance Plus ant baits from Sumitomo Chemical. Simply broadcast the bait over the lawn and garden areas, where the ants are active, and control is typically achieved within a week. However, for the invasive ant species, regular ongoing treatment may be required as nests in the neighbouring areas will reinvade over time. Both products use technology developed by Sumitomo through years of involvement in invasive ant control programs around the world. Using Synergy Pro with its two different food granules and two different actives ensures acceptance by a wide range of ant species to deliver total colony control. For sensitive accounts Distance Plus provides the ideal option; with its IGR-only formulation it is slower in action but still delivers total colony control.