Biological control of weeds is a long-term solution that is most effective when part of an integrated weed management approach.
Threat of weeds
More than 3,200 introduced plant species have become invasive in Australia and are considered weeds. Currently, a new plant species starts taking root here around every 18 days. Most of these were originally imported into Australia as decorative garden plants.
Weeds cost Australia’s economy $5 billion per year. Grain growers alone spend more than $2.5 billion per year on weed control.
Weeds are among the top three threats to the natural resources and biodiversity of Australia1. Weeds can have significant economic, environmental and social impacts in Australia and internationally, damaging natural landscapes, agricultural lands, waterways and coastal areas. In 2012, there were more exotic plant species in Australia than native plant species, indicating a likelihood of increased severity in environmental threats to native plant and animal species2.
Searching for new biological control agents
Biological control ("biocontrol") is a demonstrably sustainable and a relatively cost-effective method for managing many of Australia's most pressing agricultural and environmental weeds in the long-term.
CSIRO have demonstrated that different biocontrol agents can reduce weed populations with no adverse effects on native Australian wildlife and plant, livestock and crops, or human health. Since 1930, CSIRO (and in some instances with partners) introduced 119 different agents for biocontrol of 33 weeds in Australia. At an international level CSIRO has been involved in the successful management of the Australian broad-leaved paperbark tree (Melaleuca quinquenervia) from public lands in the Florida Everglades, USA using biocontrol agents with no non-target damage. CSIRO has also recently led the development and application of a framework to prioritise weeds as targets for biocontrol, thereby guiding investment by a range of stakeholders.
Long-term weed management
CSIRO is one of the leading global exponents of risk-analysis based biocontrol. It is one of the few agencies capable of providing biocontrol research and management support for several weeds, including those of national significance. The CSIRO Weed Biocontrol team is able to draw on its large body of expert multidisciplinary researchers to respond to weeds that over time increase in importance. CSIRO's weed biocontrol research is continually generating options for the future. Beyond measurable benefits there can be value in the options created through outcomes such as enhanced capability, improved knowledge, better research infrastructure, and a clearer understanding of the most prospective areas for future research (options value).
Download the impact evaluation report:
- Raghu et al. 2012. Weed Classical Biological Control as a Critical Component of Biosecurity: a case and strategic plan to sustain weed biocontrol capability within CSIRO. Internal CSIRO document. Theme 1077: Biosecurity and Invasive Species
- Randall, R.P. 2007. The introduced flora of Australia and its weed status. CRC for Australian Weed Management, Adelaide