Weed of the month: Boneseed

Posted on 24 October, 2024 by Lori

As Spring is well and truly underway, you will no doubt notice many of the local weeds in full flower. This October, keep an eye out for the invasive Boneseed (Chrysanthemoides monilifera subsp. monilifera), which is a Weed of National Significance (WONS) and a ‘Regionally Prohibited’ weed in the North Central Catchment – meaning landholders have a legal responsibility to control it.

Introduced from South Africa to Australia as an ornamental garden plant around the 1850s, Boneseed has become an invasive weed across southern Australia through Western Australia, South Australia, Victoria and Tasmania. Within Mount Alexander Shire, plants have been recorded at McKenzie’s Hill, Campbells Creek, Tarrengower, Chewton, Castlemaine and Kalimna.

It is a woody shrub (to 2-3 metres high) from the daisy family and produces typical ‘daisy-like’ bright yellow flowers in late winter to spring. Round hard fruit are produced during summer and spread by animals such as birds and foxes, as well as through water, garden refuse and soil movement. A single plant can produce up to 50,000 seeds a year. Seeds can germinate at any time of year, but most prolifically in Autumn after rains. They can remain viable for up to 10 years. Fire and physical disturbance can also trigger germination.

When controlling, an integrated management approach will give the best results. Manual control involves pulling out small and isolated plants at any time of the year. Herbicide control of larger individual plants using cutting and painting can be effective. In certain situations, spraying or burning may also be applicable. Only use herbicides in accordance with the label and only when plants are actively growing.

For more information on Boneseed, download a copy of the Boneseed Management Manual or visit the Agriculture Victoria website.

Landcare Groups are also a great source of information on local weeds in your area. You can find your nearest group here.

This information has been shared as part of Connecting Country’s ‘Partnerships Against Pests’ project funded by Agriculture Victoria in 2024-25. Through this program, Connecting Country will work closely with local community groups, such as Landcare, to raise awareness of local pest plant and animal issues, with the aim to empower community with the skills to address these threats. The project includes seasonal awareness campaigns around key pest issues in the region. See our news page for more information.