How To Kill Ants

The most common species of ant in Sydney are:

The Black House Ant ( Iridomyrmex glaber) and White Footed House Ant ( Technomyrmex albipes) are small black ants 2.5-3mm long. They nest in rockeries, near or under paths, in wall cavities and in potted plants. They eat a variety of foods and are attracted to sweet substances. They give an annoying bite but do not sting.

Meat Eating Ants ( Iridomyrex purpureus) are 12-14mm long and are red/purple and black. They like sunny areas and often build large gravelly mounds. They feed mainly on animal material, and honeydew. They can bite but do not sting and rarely enter houses.

Sugar or Carpenter Ants ( Camponotus species) are 5-15mm long, they have orange/brown bodies, black abdomens with an orange/brown band and black heads. They nest in decayed moist wood or sometimes in the soil. They feed on dead and live insects, honeydew, household waste and are attracted by sweet food. These ants do not sting and rarely enter houses.

Bulldog or Bull Ants ( Myrmecia species) have red bodies and black abdomens. They are about 20mm long. These ants can cause a painful sting. They rarely enter houses and are usually found in the garden or bushland areas.

Argentine Ants ( Iridomyrmex humilis) Are about 3mm long and are light to dark brown in colour. They do not have the formic acid smell ants usually have and they are very active in their movements.

White Ants are not a true ant and are correctly called “termites.”


Sanitation is important in preventing infestations by ants. To get rid of ants inside of the house, pet food bowls, dirty dishes, food crumbs on the floor, benches or tables and sap sucking insects on indoor plants can all attract ants. Outside the house, unemptied rubbish bins, food and old drink cans also encourage ants. Keeping these areas clean and controlling sap sucking insects indoors will greatly reduce the chance of ants becoming a problem around the house. Placing pet food bowls in a tray of water may lessen the problem.

Close-up photo of a Fire-Ant

Chemical Control

Chemical control may be warranted if a persistent infestation of ants causes a problem/nuisance. We prefer low-toxic chemicals or ant baits.

Types of Ants and Ant Control
To many typical householders, ants may look very similar. Many ant species are found roaming around homes & outbuildings, each species needing different methods of pest control and ant baits.

List of Most Common Species of Ant

1. Black Ant

2. White-Footed Ant

3. Bulldog Ant

4. Carpenter Ant

5. Pharaoh Ant,

6. Ghost Ant

7. Argentine Ant

8. Hairy Ant

9. Odorous Garden Ant

10. Meat Ant

11. Pavement Ant

12. Singapore Ant

13. Green-Headed Ant

14. Coastal Brown Ant

15. Native Fire Ant (Ginger Ant)

16. Red Imported Fire Ant (RIFA)

The last species has recently become a particular nuisance in recent years. Knowing which ant (s) you have often requires the help of an entomologist or knowledgeable pest control firm. Collecting a few of the non-winged worker ants in a plastic bag or vial will help with subsequent identification.
Dealing with ants can be very frustrating.

Ant Characteristics

Ants are social insects, which live together in cooperative, intermingling colonies. The colonies may range in size from hundreds to millions of individuals, depending on the species. Within each colony are different types of individuals, each with a specific function. All ant colonies contain one or more queens, whose primary role is to lay eggs. The eggs hatch into white, grub-like larvae that later transform into adult “worker” ants. The workers feed and care for the queens and developing brood, and are the ones seen foraging for food and water, often at great distances from the colony. Ants lay down invisible odour trails, which the workers follow between food and the nest. In many species, the trail of ants is distinct enough to be followed back to the nesting location, or to where the ants are entering from outdoors.

At certain times of the year, ant colonies produce large numbers of winged individuals known as swarmers. These winged ants emerge from the nest to mate and establish new colonies. When a swarm of ants emerges inside a home, it’s an indication that a nest is present within the structure. Fortunately, the success rate for swarmers establishing new colonies inside buildings is low.

Winged ants that gain entry to homes are often taken for termites.  So what is the difference between ants and termites?

The Difference between Ants and Termites

Winged ants can be distinguished from termites by comparing certain features. Ants have a narrow (pinched) waist similar to wasps, whereas termites are virtually the same width from end to end. Ants and termites each have four wings; however, on ants the front wings are longer than the hind wings while on termites all four wings are of equal size and length.

If you look closely, you will see that the antennas of ants are actually bent into “elbows” where termite’s antennae are not and are straight.

Ants will build their nests both on the inside & outside of houses and buildings. The species that will nest inside, or that forage indoors seeking food or moisture, will be the hardest to control by yourself.

Ant Control

The mistake most people make when attempting to control ants is only spraying the ones they see. This approach usually fails because the ants seen foraging over exposed surfaces is only a small portion of the colony. Typically, there will be thousands of additional ants including one or more egg-laying queens hidden somewhere in a nest. Eliminating queens and other colony members within nests is often the key to effective ant control.

Indoor Nesting

Preferred nesting sites will include wall voids, furniture, behind window-frames, under floors & concrete slabs. Many areas will be hidden, making it almost impossible difficult to work out where they are coming from. When locations of nests can’t be worked out or they are inaccessible, your will find that insecticide baits are a good option.

Ant Baits

Baits are a good option as ants will take the active ingredient back to the colony and then feed it to the other colony members, killing the queen. Most baits that you will locate in shopping centres will come with the insecticide and food attractant within a plastic, child-resistant container.
Baits are safe, easy to use & often effective. Place the baits wherever ants are seen, between the food and the nest. Don’t spray insecticides or use detergent etc around bait stations, this will stop ants from taking the bait.

You will soon see a number of ants milling around the baits DON’T SPRAY THEM!

This will indicate that ants are now feeding on the bait & getting the insecticide taken back to the nest. The activity should subside in a few days as the number of ants in the colony declines. Continue to place additional baits wherever ants are seen. Ants are rather finicky in their food preferences and may alter them throughout the year. If one bait product isn’t attractive or doesn’t seem to be working, try another. Optimal results usually require a sustained period of feeding, not just a brief visitation by a few ants. Professional pest control firms have a wider selection of bait products to choose from.

Ants Nesting Outdoors

Ants noticed inside the home may actually be nesting outdoors in the yard. Try to trace the ants back to the point where they are entering from outside. This may be along a window sill, beneath an entrance door, or where the exterior siding meets the foundation wall. Ants usually prefer to trail along lines and edges.

When you are tracing the ant trails, you need to pay attention to cracks and crevices, skirtings, the tacking strip underneath carpets, etc. Nests often will be located in the ground, marked by a mound or anthill. Sometimes, their nests will be hidden under garden mulch, pebbles, stones, timbers, retaining walls, pavement, under driveways, subfloors or under insulation inside your roof.

When a below-ground nest is discovered, the colony often can be eliminated by spraying or drenching the nest location with a liquid insecticide. Large colonies will require greater amounts of liquid to move the insecticide throughout the network of underground galleries within the nest (using a bucket to apply the diluted insecticide concentrate is an effective method). Follow label directions for treating ant mounds, paying attention to precautions for mixing and application. Another effective and convenient way to control some species of outdoor and indoor-nesting ants is with a granular bait product. Sprinkle the bait in small amounts beside outdoor ant mounds, along pavement cracks, and other areas where ants are nesting or trailing.

Physical Ant Control

Caulking around door thresholds, windows, and openings where utility pipes and wires enter buildings can reduce ant entry into homes.

Treating under doors and along foundations can reduce ant entry from outdoors.

Spraying or applying granular insecticides to the entire yard is not recommended, and will seldom, if ever, solve an ant infestation indoors. Whole-yard treatments also eliminate beneficial ants, which help to keep other damaging pests of lawns and gardens in check.

Odorous House Ants

The odorous house ant has become the most common and difficult ant species to control in Sydney, and throughout much of Australia. The ant is small, darkish, and forms distinct trails along outdoor and indoor surfaces.

It is often mistaken for the pavement ant, which can readily be controlled with most baits. The most accurate diagnostic difference, visible under magnification, is the absence of a noticeable node or “bump” along the constricted area between thorax and abdomen of the odorous house ant. Odorous house ants emit what’s been described as a rotten coconut or pine scent when crushed with a finger and sniffed.

Odorous house ants will nest in virtually every imaginable location. They commonly nest outdoors under pavement, stones, mulch, woodpiles, flowerpots, and house siding, foraging indoors for food and moisture. Nests also occur indoors within wall cavities, appliances, potted plants, etc., especially near sources of moisture.
The nests tend to be mobile; colonies relocate fast, and often in response to changes in weather and disturbance.

Ants forage indoors for food and moisture. Odorous house ant colonies tend to have numerous, egg-laying queens and the primary colonies may split into smaller ones for no apparent reason. Ants foraging indoors feed on all manner of foods, ranging from the rubbish bin to the cereal bowl.

This particular ant is difficult to control, especially by householders. As with all ants, activity indoors can sometimes be reduced by removing ready access to food and moisture (water leaks, spillage, trash cans, pet food dishes, etc). Wiping away the invisible odour trails with a kitchen cleanser or mild detergent can sometimes have temporary relief. Do not disturb foraging trails, however, if you are using bait. Caulking obvious ant entry points also may be helpful, along with trimming back shrubs and limbs touching the building. In nature, this ant feeds extensively on plant nectar and honeydew excreted by plant-sucking insects such as aphids. When odorous house ants are the problem, homeowners may be better off calling a professional, although this ant, too, challenges them. Some products used by can be effective, but are not available to the general public.

CAUTION! Pesticide recommendations in this article are registered for use in Australia only! The use of some products may not be legal in your state or country. Please check with your local county agent, pest control firm or regulatory official before using any pesticide mentioned in this publication.

Call A1 Pest Control for all pests on 0417 251 911