The first year · Month 4
On the kitchen benchAnts around the house: telling them apart and what works
Victoria’s health department says ants become a pest when they move into a building and its surrounds and feed on people’s food, and that the right way to control them depends on the species. Clean benches come first; after that, sprays, dusts and baits each have a place, and for some ants a spray makes the problem worse.
General information. Most of the practical advice here comes from Victoria’s Department of Health and is labelled as Victoria’s; the law quoted is Queensland’s. Sources are listed at the foot of this page.
Ant or termite?
A line of small insects near the skirting boards raises an obvious question about the timber. The two are not as alike as the old name “white ants” suggests.
Ants
Victoria’s health department says ants are not related to termites and cannot damage sound timber. Even the carpenter ant, it says, rarely causes structural damage.
Termites
Business Queensland says subterranean termites, commonly called white ants, only look a little like ants and are in fact more closely related to cockroaches. Around 10 native subterranean species damage timber in Queensland.
If you suspect termites rather than ants, the hiring guide explains the extra licence termite work needs.
Why only a few ants are the problem
Australia has more than 4,000 known ant species, and only a handful, mostly introduced ones, count as pests, according to Victoria’s health department. Those few tend to nest in and around buildings and gather where food is prepared, and they can spread disease.
Ants talk to each other with chemical signals called pheromones, and use them to lay trails to food. The trail on the bench is a road laid to food.
Hygiene, sprays, dusts and baits
Victoria’s health department lists four ways to control pest ants: good food hygiene, sprays, dusts and baits.
| Tool | Where it helps | Its limits |
|---|---|---|
| Hygiene | Cleaning up food scraps and residues around the house may reduce an infestation. | It has to be kept up: the page says hygiene must be maintained for complete control. |
| Surface sprays | With good hygiene, should give suitably long-term prevention. | Space sprays are of limited use against ants. A barrier treatment must be thorough, because ants are good at finding new routes to food. |
| Dusts | Applied lightly and carefully, to keep people from being exposed to them. | Not effective outside: they can be disturbed, and they only work while dry. |
| Baits | Useful where sprays and dusts cannot be used, or where the nest cannot be found. | Children’s and pets’ safety needs thought when placing them. |
Where the nest can be found, the page says, treating it directly usually works best. And expect ants back: they can recolonise from a neighbouring area within two weeks, so a second spray is often needed.
For baits at home, Queensland’s Poisons Information Centre suggests ant baits enclosed in plastic bait stations, which children find harder to get into than loose pellets or gels. Any product you use comes with a label that sets the rules; the label guide shows how to read one.
Three ants with rules of their own
The species matters most with these three, all named on Victoria’s page.
Pharaoh’s ants: don’t spray
Spraying Pharaoh’s ants breaks the colony into groups that bud off into new colonies, and that tends to make the infestation worse. The page’s method is baits in every place the ants have been seen, which can take months but is the most effective and complete approach.
Singapore ants: the power points
These ants are drawn to the plastics in electrical, irrigation and other equipment. They often nest in power sockets, chew wiring and have caused electrical fires. They are 1.5–3 mm long and can give a painful sting.
Argentine ants: the whole street
An entire block may need treating for Argentine ants, the page says.
Ants that sting
The allergy body ASCIA names the Australian jack jumper ant, a medium-sized black bull ant of eastern Australia, Tasmania and South Australia, as the main cause of anaphylaxis from ant stings in Australia. It moves with a hopping motion, is aggressive, and its sting can be severely painful. ASCIA adds that common bull ants have also been known to cause anaphylaxis, and that the green ant of Queensland causes allergic reactions too.
Queensland Health’s first aid for stings names ant stings alongside bee and wasp stings. The sting guide copies that first aid whole.
An ant with its own rules in Queensland’s law
The electric ant, Wasmannia auropunctata, has rules of its own in Queensland’s Biosecurity Regulation 2016. Inside the electric ant biosecurity zone, the regulation says, “A person must not move a live electric ant, from a place in the electric ant biosecurity zone to another place, within or outside the electric ant biosecurity zone, unless the person moves the electric ant under a biosecurity authorisation.” Things that can carry the ant are restricted too, with an exception for moving them to a waste facility the department lists as accepting them.
The Australian Government’s Outbreak reporting page lists the Exotic Plant Pest Hotline for new weeds or exotic ants, and says callers are directed to their state or territory government. Fire ants are a biosecurity response of their own in South East Queensland, with Business Queensland’s fire ant page as the place for them.