Wedderburn Conservation Management Network
Protecting Biodiversity - ​​Our Flagship Species - Malleefowl Leipoa ocellata
Wheel Cactus, Opuntia robusta
A Prickly Problem
Since 2003, The WCMN has actively combated infestations of Wheel Cactus (Opuntia robusta) within the region. Recognized as a Weed of National Significance (WoNS), Wheel Cactus thrives in the area's granitic and sandstone vegetation, posing a serious threat to native biodiversity. WCMN has dedicated countless volunteer and contractor hours to managing this invasive species, using targeted injection and spraying techniques. These ongoing efforts aim to protect the local ecosystem and preserve the unique flora and fauna of the Wedderburn area.
Wychitella and District Landcare Group
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This history highlights the group's longstanding dedication to weed management, community involvement, and collaborative efforts to protect the local landscape.
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Key Activities
1997: The group held its inaugural meeting on September 2, prioritizing weed control, including roadside weeds such as Boxthorn, Horehound, Patterson’s Curse, and Wheel Cactus.
1997-1998: Cactus was removed from roadsides using machinery and buried in designated dumps.
1999: A grant was applied for to control weed infestations on Mount Buckra and surrounding areas.
July 16, 1999: A working bee was held at the creek reserve off Wilsons Road to inject Wheel Cactus.
2005: A Field Day was held on September 5 at Buckra Hall, with a visit to a nearby hill and a large turnout.
June 10, 2005: A grant of $10,000 was secured to clean up the target area to the base of Buckra Hills.
2007: The second Field Day was held, continuing efforts to manage the weed issue.
2006-2007: Regular community days were hosted on Sundays, with support from Charlton and Wedderburn football clubs providing Labour. BBQ lunches were supplied for volunteers.
Tuesdays on Mount Buckra: Local and visiting women injected cactus. A DVD documenting their efforts was created.
2008-2009: A drought-funded program from the North Central Catchment Management Authority (NCCMA) facilitated extensive cactus injection in the Buckra Hills, covering a large area over 2.5 years. Regular workers injected an average of 10 plants per day, supported by $140,000 in wages.
2009: Working bees continued, focusing on flatter areas. The group experienced a loss with the passing of Trevor Barker, a dedicated local coordinator, in 2015. He had been instrumental in organizing events, developing a 10-year plan, and securing grants.
2014-2015: A trial plot using cochineal insects to combat the Wheel Cactus was established at the top of the group's hill. Infected pads were sourced from the Tarrengower Group, originating from South Australia. Initial concerns about bringing them across state borders proved to be unfounded.
By June 2015, the trial showed some success, with younger cactus plants being the most affected.
2015 - Present: Local landholders continue to manage weeds on their properties with chemicals supplied by the group. Volunteer contributions from Loddon Plains Landcare Network Facilitators James Nelsson and Anthony Gallacher have been particularly valuable.
The WCMN greatly appreciates the hard work and drive of the members of the WDLG and give special thanks to Janet Richardson and Beth and Bill Crutch
in driving progress to reduce this invasive species
Plant Biology and Appearance
Form: An erect succulent shrub, the Wheel Cactus can grow to a height of 1 to 2 meters.
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Stems: The plant is composed of a series of flattened, circular blue-green segments known as joints, pads, or cladodes. These segments, often mistaken for leaves, are actually modified stems, growing up to 40 cm in diameter. They are smooth (glabrous) and covered with clusters of barbed bristles called glochids, and often have 1 to 5 sharp spines up to 4 cm long from each cluster.
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Leaves: Small, scale-like, and located beneath the areoles on younger segments. These leaves fall off as the segments mature.
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Flowers: Featuring yellow petals with reddish streaks, flowers are 5 to 8 cm in diameter, growing primarily on the upper edges of the terminal segments.
Fruit: The plant produces pink to purple barrel-shaped fruits, 8 cm long and 6 cm in diameter, with dark red flesh and fine, barbed bristles.
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Roots: Wheel Cactus has a shallow and fibrous root system.
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Growth and Lifecycle
Reproduction and Dispersal: The plant spreads both by seed and vegetatively through detached segments. Viable seeds are dispersed by birds, foxes, and other animals over long distances.
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Growth and Spread: Wheel Cactus can live for several decades once established, producing numerous seeds from its many fruits.
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Seedbank Persistence: The plant's fruits each contain numerous seeds, contributing to a persistent seedbank.
Preferred Habitat and Distribution
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Habitat: Wheel Cactus thrives in arid and semi-arid regions, favoring warm temperate and sub-tropical climates with shallow granite soils. It is highly drought-resistant.
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Distribution: The species has become problematic in isolated areas of Victoria, particularly in the north-central region.
