Biocontrol of African Boxthorn
Biocontrol of African Boxthorn
A pilot project to release a biocontrol agent for the control of African boxthorn.
Collaborations -
LP020-008
The issue
African boxthorn (Lycium ferocissimum) is an introduced plant species from South Africa that that invades a broad range of farmland and native habitat in regional Australia. It forms large spiny impenetrable bush thickets that are difficult control. The CSIRO has developed the rust species Puccinia rapipes as a biocontrol agent to control African boxthorn. This would be used in conjunction with current control measures that include physical removal or chemical application.
The solution
In partnership with the CSIRO and Yanco Creek Advisory Council Inc (YACTAC) a pilot project was conducted to release the rust. Through the landholder networks of RGA and YACTAC a group of interested landholders were identified. These landholders were required to take photos of the location of for the release of the rust, photos of the health of the African boxthorns and to fill in a data sheet.
In early December a demonstration day was held on a landholder’s property at Pretty Pine where the biological control kits were handed out to each of the attendees. Andrea Mitchell (YACTAC) and Janet Manzin (RGA) explained the process for the mixing and release of the rust. Out in the paddock all of the landholders were involved in the release of the rust to 8 branches of African Boxthorns.
Landholders then took their kits back to their properties to release and monitor the development of the rust by taking photos and observing the development of the rust. All data and photos were then sent to the CSIRO for analysis. Although the results saw no rust present on the treated branches the rust could be lying dormant to re-emerge later, hence ongoing monitoring is required.
The impact
Many more landholders than kits that were available applied to be part of this pilot project. This shows the desire of the community to control African boxthorn using a different method. If successful the biocontrol agent would form part of the landholder’s weed management plan. It also shows the effectiveness of grassroots organisations to get messaging out quickly and to apply local knowledge to roll out a project of state and federal significance.
Learnings
The ideal time to release the rust is around October. Unfortunately due to flooding on the majority of landholders’ properties the demonstration day and release could not be held until December 2022. This has possibly resulted in a poor uptake of the rust on the African Boxthorn plants. It is hoped that the project will continue with another rollout towards October 2023.
Key facts
- CSIRO has developed a biocontrol agent to assist in controlling African Boxthorn.
- Landholders are enthusiastic for another control of African Boxthorn.
- Utilising Landcare group networks is an effective way for organisations and government agencies to get messaging to landholders.