Argentine ant treatment options

open areas : forested / densely wooded areas : residential areas : agricultural / livestock areas : near open water / rivers /streams : conservation areas

Argentine ant – open area

Awaiting information from NZ DOC. In the meantime treat in the same way as residential or conservation areas.

Argentine ant – forested area

Awaiting information from NZ DOC. In the meantime treat in the same way as residential or conservation areas.

Argentine ant – residential area

Option A)

Treatment products

Xstinguish (fipronil 0.1 g/kg)
Application rate 3.25 kg/ha applied in ~ 1 cm³ blobs about every 3 m

Timing

Do not apply during the wet season
Do not apply bait when rain is likely within the next 6 hours

Application method

The bait is either applied directly from the syringe or for the larger cartridges using a caulking gun
Apply the bait at approximately 3 m intervals in blobs of about 1 cm³
The bait has a tendency to dry out, so place it in spots that are sheltered from direct sunlight wherever possible

Environmental /social considerations

Fipronil is toxic to marine invertebrates and some fish, for this reason it should not be applied within 5 m of open water or areas that drain into the ocean or other open water
Ensure all stakeholders are aware baiting is taking place and that small children and other domestic animals are kept away from or know not to touch bait

Equipment required

Caulking gun
Knife
Nitrile gloves

Personal Protective Equipment

Nitrile gloves or thick gardening gloves

Health and Safety

Always read the SDS for the bait
Always wear gloves when handling bait
Always wash hands with soap and water before eating, drinking or smoking after handling bait

Option B) tested in Gisborne, NZ

Please read our note on homemade treatment products before choosing this method

Treatment products

Fipronil based: 2 parts per thousand in 80% liquid sugar as a soft agar-gel
Application rate variable

The gel bait matrix is a homemade gel made from a mixture of 4 L hot water and 3 kg white sugar, 15 g (20 ml dry) AGAR powder, 2 L warm water, 3 - 6 ml RECOIL insecticide concentrate (may be able to use other liquid baits with the active ingredient fipronil, such as PRESTO or ALBATROSS or ASCEND or TERMIDOR).

Stir ingredients together and bring just to boil to activate the Agar. Let cool a bit and dispense into squeeze-bottles or pill-vials. Can use a sheep vaccinating 5 ml pump-syringe to fill the vials with 20 ml each, or else can use 500 ml BBQ sauce bottles or equivalent. Let set overnight to a soft gel. Label container clearly as Argentine ant poison. This mixture is good stored in the fridge for up to 6 months.

Timing

Repeat applications of the bait at three week intervals until the ants are controlled. The repeats are needed to control re-established colonies from those ants being in metamorphosis stage at the first treatment
Apply the bait in the evening only, when honeybees have stopped foraging
Do not apply in severely drying conditions of full sun and warm winds
Do not apply bait when rain is likely within the next 12 hours

Application method

Syringe or squeeze bottle

IN THE EVENING, squeeze blobs of the gel into crevices, under leaf litter, under chips of bark or stones, or directly onto lawn grass or any hard, non-absorbent surface. Avoid heated concrete or stone or steel until they have cooled down in the evening
Apply the gel in dabs or short trails (10 to 20 mm long by 5 mm wide) at a density to match the density of ants observed for the area; Use a flexible pattern of 1 m X 1 m, to 2 m X 5 m, with the higher rates around garden areas, compost heaps, building foundations and observed ant trails
For some areas where there is difficult access such as steep slopes, heavy undergrowth or just a very large area to be treated, the gel can be squirted using a syringe, in bands at right-angle to the direction of travel; for example a plastic vaccinating syringe set to a 5 ml dose will jet about 5 m; By squirting alternate left and right of the walking line, at about 3 m intervals, there will be about 6 m between bait lines, with a 10 m wide zone; using about 17 L per hectare, at an a.i. rate of 34 g/ha

Bait stations

Fill 40 or so bottle-tops with the bait and in the evening lay them wherever there are trails of Argentine ants, in the morning, pick up all the lids into a tray and place all into the freezer until evening again
Or fill 30 ml pill-vials with 20 ml of the hot bait; let it set as a soft gel, then drill a 3mm hole in the vial lid, and cap it up to keep out the bees. These can be laid outdoors or indoors anytime
Where bait stations are used, place them in shaded areas at about 2 m X 2 m spacing; checking them weekly for cleaning and refill until the ants are controlled. Once an area has been cleared of ants, a boundary-line of bait stations (each 2 m) may be needed to prevent re-infestation from nearby untreated land

Environmental /social considerations

Fipronil is highly toxic to other invertebrates and fish, therefore it is advised that the product is not distributed closer than 5 m from the hide tide mark or where it may be washed into drains or waterways
The bait is highly toxic to honeybees. The risk to them is reduced in three ways: firstly by only applying bait at a density to match the observed density of ants; secondly by only spreading the bait in the evening, when bees are not flying and the ants usually clean up all the bait before morning; thirdly by placing the bait under natural covers such as stones, bark chips, or into crevices, where bees are not likely to be active
Bait stations must prevent honeybees from feeding on the bait; the entry hole must be smaller than 4 mm diameter, and the bait surface at least 10mm away from the entry hole. The gel bait must be stiff enough to bind to the inside of the bait station so that if the station is tipped over it will not flow to, or out of, the entry hole

Equipment required

Syringe or squeeze bottle

Squeezable bottle with narrow spout

Disposable animal vaccinating syringe with its feed-pipe and back-pack style reservoir (like a camel-back)

Bait stations

bottle-tops

30 ml pill-vials, with 3 mm hole drilled in the vial lid

Personal Protective Equipment

Nitrile gloves or lightweight household hygiene gloves.

Health and Safety

Always read the SDS for the bait
Always wear gloves when handling bait
Always wash hands with soap and water before eating, drinking or smoking after handling bait
Dispose of unused or dirty bait and bait stations into household dry-waste, do not wash or flush into septic disposal systems or town sewage

Information sources

Information was provided by William Dobbie, Gisborne District Council

Argentine ant – agricultural / livestock area

Awaiting information from NZ DOC. In the meantime treat in the same way as residential or conservation areas.

Argentine ant – near open water

Awaiting information from NZ DOC. In the meantime treat in the same way as residential or conservation areas.

Argentine ant – conservation area

Option A) used on Tiritiri Matangi Island, NZ

Awaiting information from NZ DOC

Option B) tested in Haleakala National Park, Hawaii, USA

Treatment products

Synergy Pro (hydramethylnon (3.5 g/kg) and pyriproxyfen (2.5 g/kg) in fish meal and corn grit/soybean oil matrix
Application rate 2.24 kg/ha

Timing

Do not apply during the wet season
Do not apply bait when rain is likely within the next 6 hours

Application method

Environmental /social considerations

Both hydramethylnon and pyriproxyfen are moderately toxic to fish and marine invertebrates and there is evidence that pyriproxyfen may accumulate in fish tissues, therefore it is advised that the product is not distributed closer than 5 m from the hide tide mark or open water

Equipment required

Manual application of granular bait

Manual spreaders
Measuring jug or scoop
Vehicle or wheelbarrow for carrying bait containers, PPE and spreaders

Personal Protective Equipment

Nitrile gloves or thick gardening gloves

Health and Safety

Always read the SDS for the bait
Always wear gloves when handling bait
Always wash hands with soap and water before eating, drinking or smoking after handling bait

Information sources

Krushelnycky. 2008. Developing techniques for invasive ant control: a test of 0.5 HP granular ant bait on Argentine ants at Haleakala National Park. Hawaii Invasive Species Council PCSU contract 438221

Option C) used on Channel islands, USA

Please read our experimental treatment section before choosing this method

Treatment products

Optigard (Thiamethoxam 0.006 g/kg) in hydrogel crystals mixed with a 25% sucrose solution
Application rate 148 L/ha

Timing

Do not apply during the wet season
Do not apply bait when rain is likely within the next 6 hours

Application method

Optigard is added to a 25% sugar solution and used to saturate dehydrated hydrogel crystals
the beads are added to the premixed sucrose and toxicant solution and left to absorb the solution for 8-12 hours
Bait may be distributed by hand using a plastic ladle to haphazardly scatter the bait or aerially by helicopter
The bait is applied every 2-3 weeks for six months (summer-autumn)
Any remaining nests can be treated with a paste made from a mixture of the Optigard sugar solution and egg and spread or sprayed directly on the nests

Environmental /social considerations

Two articles posted on the Washington State University Extension site Horticultural Myths bring the safety of hydrogel crystals into question
Hydrogel crystals are made from polyacrylamide, which breaks down (particularly quickly in the presence of fertilisers) releasing potassium acrylate acrylamide and acrylonitrile
Acrylamide is a potent neurotoxin that has also been demonstrated to be carcinogenic. However, it is broken down in a matter of days
Acrylamide is soluble and may enter the water table, but it is not taken up by plant root systems
Acrylonitrile is a US EPA regulated substance that is a possible carcinogen and is toxic to aquatic life
Further environmental impact information for this treatment would be useful here

Equipment required

Broadcast with manual spreaders

Measuring jug or scoop
Vehicle or wheelbarrow for carrying bait containers, PPE and spreaders

Personal Protective Equipment

Nitrile gloves or thick gardening gloves

Health and Safety

Always read the SDS for the bait
Always wear gloves when handling bait
Always wash hands with soap and water before eating, drinking or smoking after handling bait

Information sources

Boser, Hanna, Faulkner, Cory, Randall, Morrison. 2014. Argentine ant management in conservation areas: results of a pilot study (download 2 MB). Monographs of the Western North American Naturalist 7: 518-530

Boser, Hanna, Holway, Faulkner, Naughton, Merrill, Randall, Cory, Choe, Morrison. 2017. Protocols for Argentine ant eradication in conservation areas. Journal of Applied Entomology DOI: 10.1111/jen.12372