Key points

• Herbicide resistance is the most common weed management concern across Australia’s cropping regions, research shows
• Area-wide management can reduce these impacts by supporting land managers to cooperatively work towards reducing resistance spread
• However, this option predominantly exists only in theory, rather than in practice
• New social science research is uncovering why, in a bid to help design and implement better management strategies

Although many grain growers believe area-wide weed management has benefits, they are equally concerned over its potential costs – with time constraints the biggest worry.

A survey by the University of Wollongong has uncovered how growers feel about weed management, its costs, and barriers to adopting area-wide weed management. It found that too much potential time spent in meetings topped a list of grower concerns, with 65 per cent of respondents noting this.

The other issues perceived by growers were limited options for organic systems (at 62 per cent), herbicide use restrictions (55 per cent) and changing spraying operations to accommodate neighbours (55 per cent).

Researchers from the university’s School of Geography and Sustainable Communities interviewed 604 growers between July and September 2021. They included 186 growers from the Darling Downs, Queensland; 218 from the Riverina, New South Wales; and 200 from Sunraysia, Victoria.

University of Wollongong social scientist Dr Sonia Graham says there is a broad knowledge-action gap between understanding the need for collaboration and timely practice on-ground. Photo: Supplied

The survey is part of a broader GRDC-supported project on area-wide weed management. It is supported through funding from the Australian Government Department of Agriculture, Water and the Environment as part of its Rural R&D for Profit program and the GRDC and the Cotton Research and Development Corporation.

It is also supported by nine other organisations and aims to identify what support is needed to implement this type of weed management in Australia’s cropping systems.

The lead researcher, social scientist Dr Sonia Graham, says there is a broad knowledge-action gap between understanding the need for collaboration and timely practice on the ground.

The team’s work is uncovering why to help design and implement future strategies.

Area-wide management

Area-wide management can involve participating in weed management activities with other land managers, such as discussing weed management with neighbours, or managing weeds on public property.

Already, one in four growers participate in area-wide management (see snapshot) and it has gained more traction in the past decade as researchers recognise that addressing herbicide resistance requires cross-property collaboration.

Australia has 49 herbicide-resistant weed species and extensive evolution of weed populations with resistance to multiple herbicides.

The survey found growers also believed there were benefits in collaborative action. They identified these as increased awareness of new weeds in the area (95 per cent), increased awareness of herbicide-resistant weeds in the area (91 per cent) and getting ahead of weed spread in the area (89 per cent).

Dr Graham says these concerns reflect the potential for not only herbicide-resistant weeds to spread across the landscape but also for a new approach “that goes beyond applying best management practices at the farm scale”.

The project team will use these results to examine what influences participation in collaborative weed management activities.

“The results indicate high levels of agreement among growers about the need for collaboration and the benefits that can come from working together on weeds.

“However, at the moment it is an option that predominantly exists in theory, rather than in practice. So, how do we get buy-in? We need to understand more to develop any future management plans.”

Survey snapshot

In late 2021, 604 growers were interviewed about area-wide management. Of these:

• 45 per cent identified as grain producers;
• 43 per cent as grain and sheep producers; and
• 12 per cent as grain and beef producers.

Production-wise:

• 37 per cent derive most of their income from cropping; and
• wheat, at 89 per cent, was the most commonly grown crop, followed by barley at 68 per cent and canola at 54 per cent.

Weed control costs, including herbicides, equipment and labour:

• account for 21 to 30 per cent of farm costs for 28 per cent of growers;
• account for 11 to 20 per cent of farm costs for the same proportion of growers; and
• concern more than half (at 56 per cent) of respondents.

Growers were most concerned about fleabane at 77 per cent, followed closely by ryegrass at 76 per cent.

Already, 24 per cent of growers participate in weed management activities that involve other land managers. This most frequently includes:

• discussing weed management with neighbours (33 per cent do this frequently or always); and
• managing weeds on public property (32 per cent do this frequently or always).

The project involves 11 research and development partners: GRDC, the Cotton Research and Development Corporation, AgriFutures Australia, CSIRO, University of Queensland, University of Adelaide, University of Wollongong, Mallee Sustainable Farming, Millmerran Landcare Group, Irrigation Research & Extension Committee Inc and the Toowoomba Regional Council.

More information: Sonia Graham, sgraham@uow.edu.au