African boxthorn

African boxthorn

African boxthorn

African boxthorn was originally brought to Australia to provide livestock with shelter and for use as a confinement hedge. Now a declared weed, boxthorn is widespread in the region and is found on roadsides, in pastures and native vegetation.

What is African boxthorn?

African boxthorn is an erect, deep-rooted shrub with spine-tipped, densely tangled twigs. It has a deep and branched root system that can produce sucker shoots if broken.

African boxthorn

African boxthorn has light green, fleshy, and oval-shaped leaves with white and purple flowers. Flowering and fruiting occur throughout the year but particularly in spring. Plants produce round, orange-red berries that contain seeds. Their seeds are the main method of reproduction and can germinate at any time of the year.

Where is African boxthorn found?

African boxthorn is widespread in the Murraylands and Riverland as it is able to grow in a range of climates, habitats and soil types. It can be found along fences, waterways, roadsides, railway lines, agricultural land and in native vegetation.

Recorded African boxthorn outbreaks in the Murraylands and Riverland region*

What are the impacts of African boxthorn?

The thorny bushes form dense impenetrable thickets, restricting the movement of stock, humans, and vehicles, also providing harbour for pests such as foxes and rabbits. African boxthorn competes with desirable pasture plants and restricts native vegetation. In watercourses, the presence of African boxthorn can prevent animals from accessing water.

Once established, is difficult and expensive to control, often requiring heavy machinery to complete physical removal. Fruit may be toxic to humans and spines can inflict painful injuries. The fruit is also listed as a fruit fly host, posing a threat in areas such as the Riverland.

What is the declared status of African boxthorn?

African boxthorn is declared in South Australia and is subject to the following restrictions:

• Land owners and managers to take reasonable steps to kill plants and prevent their spread,

• Plants must not be sold or traded in any way, including as a contaminant of anything,

• Plants must not be transported on a public road, including as a contaminant of anything.

When is the best time to monitor for and control African boxthorn?

Successful weed control relies on follow up after the initial efforts by monitoring for and killing regrowth or new seedlings. Using a combination of control methods is usually more successful:

• treat mature plants when they are actively growing, typically in the cooler months after rains in the Murraylands and Riverland region

• kill young plants before they are 2 years old to prevent seed set

• follow-up until African boxthorn is eradicated

• promote vigorous perennial pastures to resist invasion.

More information about control options, including specific herbicide rates, can be found on the PIRSA website.

African boxthorn

How can African boxthorn be prevented?

Prevent entry on to your property by ensuring your stock, machinery and purchases of seed, soil and fodder are free of weed seed. Quickly identify and treat weeds using the recommended measures and continue follow up treatments until the weed is killed. Work with neighbours in the area to search for and control African boxthorn, to reduce likelihood of seed spread by birds and foxes.

What to do if you suspect an African boxthorn outbreak

If the plants are actively growing on your land, remove and destroy the plant or treat with chemicals until plant is killed. Always follow up after the initial efforts.

For support in identifying and controlling African boxthorn, contact your local district officer.

African boxthorn

This project is supported by the Murraylands and Riverland Landscape Board with funding through the landscape levies.

*Map provided as a guide only. Mapped outbreaks are not necessarily current or comprehensive.