When someone says they have a “green ant” problem, the type of ant they are referring to will depend on where they live. For most of Australia, green ants or more accurately green-head ants are biting ants that are found in lawns across most of Australia. For those in the tropical north, people are referring to the green tree ants (also called weaver ants), which build their nests in trees.
Green-head ants (Metallica Rhytidoponera)
Green head ant
Where do they live?
Green-head ants are found Australia wide and are commonly found in urban areas and forests.
Nest description
The nests are normally found in lawns and under rocks and logs. Normally
Behaviour
Green-head ants typically only forage when the sun is out. They have a broad diet but prefer animal material obtained through scavenging and predation. They normally only have one nest but with several queens. The queens look very similar to the workers and also forage.
Pest status
As green-head ants like to build their nests in lawns and can deliver a painful sting, an infestation can make lawns unusable by children and pets.
Bite symptoms
The sting can be painful generating local redness and swelling. The sting site may itch for several days.
Bite treatment
An ice pack immediately after being stung to reduce the pain. Medications to reduce itching can be used if required. If the patient suffers an allergic reaction, seek medical help immediately.
Control treatments
Green-head ants are most effectively controlled using granular baits, such as PestXpert Nest Kill Bait. The bait is taken back to the nest where it is shared with other colony members. As it is important that all the queens are eliminated, this is a very effective ant control treatment. Baits are slow acting by design (to ensure they are spread through the colony) – there should be a big drop off in foraging numbers in 2-3 days with colony control in 1-2 weeks. PestXpert Nest Kill Ant Bait comes in 150g and 500g pack sizes options for all sizes of lawns.
Green tree ants (Oecophylla smaragdina)
Green tree ant
Where do they live?
Green tree ants are found on the east coast from Gladstone into the tropical north, around into the Northern Territory and into the Kimberly region of WA.
Nest description
Green tree ants are arboreal – they live in trees, rarely coming to the ground. They build their nest by pulling leaves together and gluing them with excretions. Colonies can be extremely large, covering many trees and containing several hundred thousand workers.
Green tree ants ‘glue’ leaves together to make their nests in bushes and trees
Behaviour
Green tree ants feed on other insects they find in the trees and also ‘farm’ small bugs (Hemiptera) that excrete a sugary honeydew. They are very aggressive ants defending their territory.
Pest status
Green tree ants are sometimes used by indigenous farmers and as a biocontrol agent, as they are very effective and removing pest insects from tree crops. However, they do make harvesting problematic due to their aggressive behaviour. For homeowners, their presence in trees and shrubs can make gardening problematic.
Bite symptoms
Green tree ants don’t have a sting, but they can bite and also have the ability to spray formic acid, which can hurt if it gets into the bite.
Bite treatment
Wash any bite and use a cold pack to relieve any pain.
Control treatments
Green tree ants do not forage readily on baits. The best method of control is through direct nest treatments, although in cases of a large colony, finding and treating all the nests can be a challenge. PestXpert Pro-Spray Outdoor perimeter is an ideal product to treat each nest. With its 1 m metal spray wand, it is easy to insert into the nest chamber and treat the nest, whilst keeping your distance!