It’s not only ants inside the home that customers want gone – controlling ants in the lawn, especially biting ants, presents a significant revenue opportunity to pest managers. 

Homeowners tend to give pest control companies a call when they are suffering ant problems inside the home. However, quite often they are unaware of other ant problems outside the home, which are potential sales opportunities for the observant pest professional. Let’s look at the top three ‘lawn ants’ that can provide significant add-on value to a service visit.

Big-headed ants (Pheidole megacephala)

Big-headed ants or coastal brown ants are one of the major global, invasive ant species. In common with many of the worst invasive ant species, the big-headed ant is a multi- nest, multi-queen species which can dominate an area, making it very difficult to provide lasting control.

Although they can nest in lawns where soil from their excavating can been seen, it is under the pavers of paths and driveways that they cause their biggest damage. They can remove a significant amount of sand from under the pavers, often in short time. Not only does this create an unattractive appearance, it can quickly undermine the pavers making the surface uneven.

Big-headed ants undermining pavers

Although complete colony elimination is often impossible due to their multi-nest, multi-queen colony structure, there are some good options to get at least temporary relief.

Spraying in between paver cracks with a non-repellent spray will kill the ants present and have the potential for a magnified effect through insecticide transfer, potentially killing a ‘sub-nest’. The use of suitable pyrethroid sprays or granules can also be considered – they will kill the ants present and exclude ants from the area, often for a couple of months.

These paver treatments can be combined with bait treatments in other areas to provide a longer lasting control. Granular corn grit based baits can provide good colony control. However, the duration of protection depends on the extent of the infestation as they can always re-invade from the surrounding (untreated) areas.

Green-head ants (Rhytidoponera metallica)

Green-headed ants are found in most parts of Australia.

Most of us will be aware of their very painful bite and the subsequent itching for days afterwards. For the few that suffer severe allergic reactions to such bites, a green-headed ant encounter can be a serious health risk.

Green-headed ants typically build their nests in lawns or under rocks and logs, normally with one or two openings. They are very aggressive ants, which will attack when disturbed.

The ants tend to forage in sunshine and are omnivores with a preference for protein. Green-headed ants form single nests, although the nests contain multiple reproductives. Interestingly, the reproductives look superficially the same as the workers and also forage.

Excellent control is achieved by using granular baits with a corn grit component. It is important to ensure enough bait is provided to this species to get complete control, as it is known to avoid baits that have provided a sub-lethal effect to the colony. Sometimes after treatment, surviving workers are seen transporting pupae away from the treated nest.

Green-headed ant nest after granular bait treatment

Funnel ants (Aphaenogaster pythia)

Funnel ants are quite secretive, but the results of their excavations are very obvious. Lawns suffering a funnel ant infestation will look like a lunar landscape (main picture, above). Although the funnels can be knocked down by mowing, they can be rebuilt by the ants overnight, especially after rain.

Apart from disfiguring lawns, which can be expensive to repair and potentially impact house prices, their activities can cause areas of the lawn to collapse resulting in damage to mowers and potential injury through twisted ankles.

There are several species of funnel ant, but the species that causes problems with lawns is generally restricted to the eastern seaboard north of Sydney. Although it can be widespread in certain suburbs where the soil type is ideal, their distribution can be patchy within such suburbs due to the grass types in the lawns.

Funnel ants are ominvores, but it is believed they feed off aphids found on the roots of certain grasses, supplemented with insects that fall unwittingly into their funnels.

Their extensive underground nest structure means direct nest injection to control major infestations is likely to fail. The proven way to control funnel ants is to use fipronil treatments as a liquid spray on and around their funnels or granular fipronil formulations applied to the same areas and watered in. Funnel ants pick up the fipronil as they work the soil and pass it on to their nest mates, providing excellent colony control.

Depending on the formulation and dose, with fipronil remaining in the soil for a prolonged period, lawns have been known to remain clear from funnel ants for a year or more.

Typically, for lawn ant treatments, ant jobs should be costed on an area basis. A key component of the pricing will depend on the duration of the warranty you offer – is the homeowner getting value for money? Speak to the product manufacturers to discuss duration of protection, although this is very dependant on the level of infestation at the property, so you may need to be flexible.

But it’s worth developing some specific treatments and packages for lawn ants, they can certainly be a profitable add-on service.