Wheel cactus is an erect succulent plant with circular pads and yellow flowers. It forms dense thickets that restrict movement of people and animals.
This weed belongs to the group Prickly pears - Opuntias
This plant must not be sold anywhere in NSW
This plant is a Weed of National Significance
Wheel cactus forms dense thickets that outcompete low growing plants and prevent movement of animals and people. This means that:
• animals may not be able to access feed
• mustering is difficult
• access to watering points is reduced
• recreational activities such as bushwalking and camping are restricted.
Most plants have sharp spines that can:
• cause painful injuries to people, livestock, working dogs and pets
• injure and sometimes kill native wildlife that get trapped in the spines
• devalue wool and hides and prevent shearing
• get stuck around the mouth of lambs or calves and prevent them from feeding.
Wheel cactus competes with native plants, reducing food and habitat for native animals.
Wheel cactus is a succulent shrub usually 1–2 m tall. Sometimes it is treelike with a distinct trunk and up to 4 m tall. Cacti pads have bumps on the surface called areoles. Spines, bristles, leaves, flowers, fruit, roots and new shoots all grow out of the areoles.
In NSW, most infestations are in the Western Region. There has been one infestation in the South East in the Snowy Mountains.
Wheel cactus is a native plant in Mexico. It was introduced into Australia as an ornamental plant.
Wheel cactus grows in a wide range of climates. It mostly grows in arid, semi-arid warm temperate and subtropical climates but it can tolerate cooler temperate areas.
It is very drought tolerant. Plants can survive extremely high temperatures up to 50 °C and low temperatures down to -7°C.
It tolerates a wide variety of soil types and grows very well in shallow granite soils.
By seed
Seeds are spread by birds (including emus), foxes and ants. Plants that grow from seeds do not produce fruit until they are at least 3 years old. Seeds are usually only dormant for one year.
Plant parts
New plants can grow from parts of the stem when they come in contact with the soil. Stem fragments can be spread by flood water and by people dumping garden waste.
Baker, J., Keller, M., & Preston, C. (2008). Genetic variability of wheel cactus (Opuntia robusta Wendl.) in southern Australia: implications for weed spread and biological control. In Proceedings of the 16th Australian Weeds Conference (pp. 18-22).
Del Castillo, R. F., & Argueta, S. T. (2009). Reproductive implications of combined and separate sexes in a trioecious population of Opuntia robusta (Cactaceae). American Journal of Botany, 96(6), 1148-1158.
Harvey, K.J., McConnachie, A.J. Sullivan, P. Holtkamp, R. & Officer, D. (2021). Biological control of weeds: a practitioner's guide for south east Australia. New South Wales Department of Primary Industries, Orange.
Nobel, P. S., & Zutta, B. R. (2008). Temperature tolerances for stems and roots of two cultivated cacti, Nopalea cochenillifera and Opuntia robusta: Acclimation, light, and drought. Journal of Arid Environments, 72(5), 633-642.
Parsons, W. T., & Cuthbertson, E. G. (2001). Noxious weeds of Australia. CSIRO publishing.
PlantNET (The NSW Plant Information Network System). Royal Botanic Gardens and Domain Trust, Sydney. Retrieved 14 April 2021 from: https://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Opuntia~robusta
Sheehan, M. R., & Potter, S. (2017). Managing Opuntioid Cacti in Australia: Best Practice Control Manual for Austrocylindropuntia, Cylindropuntia and Opuntia Species. Department of Primary Industries and Regional Development.
Snyman, H. A. (2006). Root distribution with changes in distance and depth of two-year-old cactus pears Opuntia ficus-indica and O. robusta plants. South African Journal of Botany, 72(3), 434-441.
Successful weed control relies follow up after the initial efforts. This means looking for and killing regrowth or new seedlings. Using a combination of control methods is usually more successful.
Act early by removing any individual plants before they spread.
Do not grow wheel cactus in gardens or pots. Do not take cuttings of unknown cactus plants to grow out or share with others.
Avoid driving through areas with cacti. If you have been in an area with cacti check under vehicles, caravans, and machinery before leaving the infested area. Remove all plant parts using pliers or tongs. Dispose of them appropriately.
Dig up small or isolated plants using a mattock or other tools. Wear appropriate protective clothing and gloves to protect against injuries from the spines and bristles.
Larger infestations may be controlled by machinery. Ensure the roots are dug out and that all plant parts are disposed of.
Dispose of wheel cactus by burying it at least one metre deep or by burning in a hot fire. Check disposal sites regularly and control any seedlings. Contact your local council for information about other disposal options.
Two types of cochineal insect can effectively control large, dense infestations of wheel cactus:
Control will take several years. Biological control is suitable for areas that are environmentally sensitive, too difficult to access or where other methods would be too expensive. Cochineal insects are less effective on scattered infestations and may require redistribution at these sites.
There are several species of cochineal that look very similar. It is important to use the correct species of cochineal for each species of cactus. Contact your local council weeds officer for information about using cochineal to control wheel cactus.
The cactoblastis moth Cactoblastis cactorum attacks wheel cactus but only provides limited control.
Herbicides are especially useful for sparse, scattered infestations.
Spray when plants are actively growing. Thoroughly cover all parts of the plants with herbicide mix. Plants may regrow after spraying and follow up applications may be required.
Wear the appropriate personal protective clothing described on the herbicide label. Drill into the base of the stump with a long bit on a battery drill to avoid thorns and inject with a handheld injection gun and forestry spear.
See Using herbicides for more information.
PERMIT 14442 Expires 30/06/2023
Picloram 100 g/L + Triclopyr 300 g/L + Aminopyralid 8 g/L
(Grazon Extra®)
Rate: 500 mL per 100 L of water plus 0.5% Uptake spray oil.
Comments: Apply to actively growing plants. See permit for critical use comments.
Withholding period: Where product is used to control woody weeds in pastures there is a restriction of 12 weeks for use of treated pastures for making hay and silage; using hay or other plant material for compost, mulch or mushroom substrate; or using animal waste from animals grazing on treated pastures for compost, mulching, or spreading on pasture/crops.
Herbicide group: I, Disruptors of plant cell growth (synthetic auxins)
Resistance risk: Moderate
PERMIT 14442 Expires 30/06/2023
Picloram 100 g/L + Triclopyr 300 g/L + Aminopyralid 8 g/L
(Grazon Extra®)
Rate: 50 mL per 10 L of water plus 50 mL Uptake spray oil.
Comments: Knapsack application. A spray volume of 3 L to 4 L per 10 m2 should be used. See permit for critical use comments.
Withholding period: Where product is used to control woody weeds in pastures there is a restriction of 12 weeks for use of treated pastures for making hay and silage; using hay or other plant material for compost, mulch or mushroom substrate; or using animal waste from animals grazing on treated pastures for compost, mulching, or spreading on pasture/crops.
Herbicide group: I, Disruptors of plant cell growth (synthetic auxins)
Resistance risk: Moderate
PERMIT 14442 Expires 30/06/2023
Triclopyr 300 g/L + Picloram 100 g/L
(Various products)
Rate: 500 mL per 100 L of water plus 0.5% Uptake spray oil.
Comments: Spot spray application. Spray actively growing plants. See permit for critical use comments.
Withholding period: Nil.
Herbicide group: I, Disruptors of plant cell growth (synthetic auxins)
Resistance risk: Moderate
PERMIT 14442 Expires 30/06/2023
Triclopyr 300 g/L + Picloram 100 g/L
(Various products)
Rate: 50 mL per 10 L of water plus 50 mL Uptake spray oil.
Comments: Knapsack application. A spray volume of 3 L to 4 L per 10 m2 should be used. See permit for critical use comments
Withholding period: Nil.
Herbicide group: I, Disruptors of plant cell growth (synthetic auxins)
Resistance risk: Moderate
PERMIT 14442 Expires 30/06/2023
Triclopyr 600 g/L
(Garlon® 600)
Rate: 50 mL per 10 L of water plus 50 mL Uptake spray oil.
Comments: Knapsack application. A spray volume of 3 L to 4 L per 10 m2 should be used. See permit for critical use comments.
Withholding period: Nil.
Herbicide group: I, Disruptors of plant cell growth (synthetic auxins)
Resistance risk: Moderate
PERMIT 14442 Expires 30/06/2023
Triclopyr 600 g/L
(Garlon® 600)
Rate: 1 L in 75 L of diesel.
Comments: Spot spray application. Spray actively growing plants. See permit for critical use comments.
Withholding period: Nil.
Herbicide group: I, Disruptors of plant cell growth (synthetic auxins)
Resistance risk: Moderate
PERMIT 14442 Expires 30/06/2023
Triclopyr 600 g/L
(Garlon® 600)
Rate: 3 L per 100 L of water plus 0.5% Uptake spray oil.
Comments: Spray actively growing plants. See permit for critical use comments.
Withholding period: Nil.
Herbicide group: I, Disruptors of plant cell growth (synthetic auxins)
Resistance risk: Moderate
The content provided here is for information purposes only and is taken from the Biosecurity Act 2015 and its subordinate legislation, and the Regional Strategic Weed Management Plans (published by each Local Land Services region in NSW). It describes the state and regional priorities for weeds in New South Wales, Australia.
Area | Duty |
---|---|
All of NSW | General Biosecurity Duty All pest plants are regulated with a general biosecurity duty to prevent, eliminate or minimise any biosecurity risk they may pose. Any person who deals with any plant, who knows (or ought to know) of any biosecurity risk, has a duty to ensure the risk is prevented, eliminated or minimised, so far as is reasonably practicable. |
All of NSW |
Prohibition on certain dealings
Must not be imported into the state, sold, bartered, exchanged or offered for sale. |
Central Tablelands |
Regional Recommended Measure* (for Regional Priority - Asset Protection)
Land managers should mitigate the risk of the plant being introduced to their land. Land managers should mitigate spread of the plant from their land. A person should not buy, sell, move, carry or release the plant into the environment. Land managers should reduce the impact of the plant on assets of high economic, environmental and/or social value. |
Central West |
Regional Recommended Measure* (for Regional Priority - Asset Protection)
Land managers should mitigate the risk of the plant being introduced to their land. Land managers should mitigate spread of the plant from their land. A person should not buy, sell, move, carry or release the plant into the environment. Land managers should reduce the impact of the plant on assets of high economic, environmental and/or social value. |
Hunter |
Regional Recommended Measure* (for Regional Priority - Asset Protection)
Land managers should mitigate the risk of the plant being introduced to their land. Land managers should mitigate spread of the plant from their land. A person should not buy, sell, move, carry or release the plant into the environment. Land managers should reduce the impact of the plant on assets of high economic, environmental and/or social value. |
Murray |
Regional Recommended Measure* (for Regional Priority - Containment)
Whole of region: Land managers should mitigate the risk of the plant being introduced to their land. Land managers should mitigate spread of the plant from their land. A person should not buy, sell, move, carry or release the plant into the environment. Land managers should reduce the impact of the plant on assets of high economic, environmental and/or social value. |
Western |
Regional Recommended Measure* (for Regional Priority - Asset Protection)
Land managers should mitigate the risk of the plant being introduced to their land. Land managers should mitigate spread of the plant from their land A person should not buy, sell, move, carry, or release the plant into the environment. Land managers should reduce the impact of the plant on assets of high economic, environmental and/or social value. |
*To see the Regional Strategic Weeds Management Plans containing demonstrated outcomes that fulfil the general biosecurity duty for this weed click here |
Reviewed 2023