Mimosa pigra Symposium

The proceedings of the 3rd International Symposium on the Management of Mimosa pigra, held in Darwin, Australia on 23-25 September 2002, have been published*.

In the 10 years since the last meeting in this symposium series there has been marked progress in the management of M. pigra, particularly in the areas of biological and integrated control. Also, indigenous management issues have assumed much greater importance in mimosa management in a number of countries.

More than 70 participants from Australia, Cambodia, Indonesia, Sri Lanka, Thailand and Vietnam attended the 3-day workshop that formed the 3rd International Symposium. The meeting included a daylong field visit to inspect integrated management trials near Darwin, and two days during which participants heard 26 presentations. The papers, which represent the most up-to-date source of information on research and management of M. pigra, are incorporated into these proceedings, together with a summary of recommendations on key issues, which emerged from discussion sessions held during the workshop.

Topics covered included taxonomy (one paper), risk assessment (one), status, threat and impact (four), mapping (two), modelling (one), use (two), public awareness and education (one) and prevention and early intervention (one). However, the important advances made in management and control are reflected in the other 13 papers on these topics.

Except in Australia, control initiatives for M. pigra are relatively recent. A paper from Sri Lanka describes community-based activities, and evaluates chemical and mechanical measures; it also notes that Panicum maximum was observed to prevent M. pigra germination. Two papers from Vietnam also assess chemical and mechanical measures, and describe the threat the weed poses to sites of conservation importance. A paper from Thailand evaluates introduced bruchid biological control agents and concludes that limited seed damage means further measures are needed.

The remainder of the control and management papers are from Australia, reflecting its 40 years' experience with the weed (including 23 years with biological control). One paper discusses choice of chemicals and application methods, another the integration of mechanical and biological methods. Other papers deal with biological control per se, covering prospects for fungal agents through inundative methods, and methods for assessing agent impact; tantalizingly, as the results of the evaluations are to be published in peer-reviewed journals, readers will have to wait for those, but the methods described can be adopted elsewhere. A paper on the impact of control on the seed bank in Australia indicates that further measures are still needed. Nonetheless, there is encouraging news in two papers describing how the weed is being successfully contained by mechanical means at a small, recently invaded site, and through community-based action on another, much larger, established area of infestation. A useful review of the assessments made on 45 prospective agents by the Australian programme (13 of which have been released there) and seven more currently being studied is one of several papers in these proceedings that provide information for countries embarking on M. pigra counter-initiatives. Another of these, the final paper, looks to the future; it identifies agents currently having an impact in Australia (the beetles Acanthoscelides puniceus and Coelocephalapion pigrae and the moths Neurostrota gunniella and Carmenta mimosa) together with insect and fungal species considered to have potential, and provides an overview of the prospects for mimosa control in Australia and other affected countries the 21st century.

^*Julien, M., Flanagan, G., Heard, T., Hennecke, B., Paynter, Q. & Wilson, C. (eds) (2004) Research and management of Mimosa pigra. Papers presented at the 3rd Symposium on the Management of Mimosa pigra, 23-25 September 2002, Darwin, Australia. CSIRO Entomology, Canberra, 173 pp.

Contact and copies: Mic Julien and Tim Heard, CSIRO Entomology, 120 Meiers Rd, Indooroopilly 4068, Brisbane, Australia.
Email: mic.julien@csiro.au/tim.heard@csiro.au

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