Native to southern Africa, African boxthorn is a spiny shrub introduced to Australia in the mid 1800s as a hedge plant. It has since spread to pastures, neglected areas, roadsides, railways and waterways. African boxthorn produces dense, spiny thickets that can form impenetrable barriers to stock and people.
African boxthorn is a restricted invasive plant under the Biosecurity Act 2014.
- Perennial shrub up to 5m tall with deep, extensive, branched root system.
- Stems are rigid, branched, woody, thorny.
- Leaves are bright green, 3cm long, 2cm wide, rounded at top, tapered to base.
- Flowers are white to pale mauve, 12mm diameter.
- Berries are smooth and green when young, ripening to bright orange to red.
- Seeds are numerous, light brown, oval, flattened.
- Prefers better soils of Maranoa and Darling Downs districts, where it is an aggressive weed.
- Grows on all soil types but establishes better in lighter soils, particularly along dry creek beds.
Distribution in Queensland
- Occurs in non-coastal areas of South East Queensland and recorded in Hughenden and Charleville.
- Seeds may germinate at any time of year, and quickly establish a root system to allow young plants to compete with other species.
- Plants are at least 2 years old when they first bear flowers, generally in summer.
- Flowering and fruiting may occur at any time throughout the year.
- Invades reserves and conservation areas.
- Aggressively invades pastures and reduces useability.
- Invades roadsides.
- Forms impenetrable, spiny thickets, which can hinder stock movement and mustering.
- Provides habitat for pest animals such as rabbits.
- Attracts insects, including fruit fly, dried fruit beetles and tomato fly, which breed in the fruit.
- Forms impenetrable, spiny thickets that can hinder bush walking.
How it is spread
- Spread by birds and animals eating berries and excreting viable seed.
- Hand-pull young plants.
- Clear large stands of boxthorn by dozing, stickraking or blade ploughing.
- Control regrowth from seed or remaining roots using cultivation and herbicides.
- Spray entire bush to point of run-off.
- If possible, spray in February−May, when plants are actively growing.
- Do not spray during hot, dry summer periods.
Basal bark treatment
- Carefully spray around the base of each stem to a height of 30-40cm above ground level.
Cut stump treatment.
- Cut each stem off as close as possible to the ground and immediately (within 15 seconds) apply herbicide mixture liberally to cut surface.
- Apply a residual herbicide to the soil between the base of the plant and the drip line, preferably when soil is wet or rain is expected.
See the African boxthorn fact sheet (PDF, 3.3MB) for herbicide control and application rates.
- African boxthorn has not been a target for biological control.
- No known biological control agent.
- African boxthorn is a restricted invasive plant under the Biosecurity Act 2014.
- It must not be given away, sold, or released into the environment without a permit.
- The Act requires everyone to take all reasonable and practical steps to minimise the risks associated with invasive plants and animals under their control. This is called a general biosecurity obligation (GBO).
- At a local level, each local government must have a biosecurity plan that covers invasive plants and animals in its area. This plan may include actions to be taken on certain species. Some of these actions may be required under local laws. Contact your local government for more information.
- Last updated
- 01 July 2016