Flaxleaf fleabane (photo courtesy of M. Widderick QDAF)

Flaxleaf fleabane (Conyza bonariensis) is a major weed of cropping in northern New South Wales and southern Queensland. This weed is estimated to cause revenue losses in excess of $43 million for grain producers. Development of resistance to herbicides is making populations increasingly difficult to manage in these agricultural environments. Biological control is a potentially useful and valuable tool for the management of flaxleaf fleabane given the success of previous biological control programs against other weeds in the Asteraceae family such as Parthenium hysterophorus and Chromolaena odorata.

This research on flaxleaf fleabane has been part of the projects ‘Biocontrol solutions for sustainable management of weed impacts to agricultural profitability’ (2016-2020) and ‘Underpinning agricultural productivity and biosecurity by weed biological control‘ (2019-2022), led by AgriFutures Australia (the trading name of the Rural Industries Research and Development Corporation (RIRDC)). These projects have been supported by funding from the Australian Government Department of Agriculture, Water and the Environment as part of its Rural R&D for Profit programme rounds 2 and 4, respectively. The Grains Research and Development Corporation (GRDC) and the NSW Biocontrol Taskforce are also acknowledged for their financial support.