Effective control of brome grass in the southern and western cropping zones

Bromegrass is a serious weed of many Australian cropping regions but is widespread across the sandy soils of the low-medium rainfall zone of WA, SA, Vic and south-western NSW. It is estimated to cause $22.5M in loss of revenue annually across all regions, which is fourth on the list of cropping weeds. There are continued reports from areas such as the low rainfall regions of WA (Geraldton Port Zone, Kwinana East and Kwinana West), Southern NSW and the southern region low rainfall zone that brome grass is still causing significant impacts and is especially damaging in dry years.

The control of brome grass has previously relied upon Group 2 (B)herbicides in cereal crop sand Group 1 (A) grass selective herbicides in broadleaf crops. Significant resistance to SU herbicides has been found and Group 1 resistance is developing. Practical farm management relies heavily on Clearfield technology, which can be very effective. However, reliance on this chemistry imparts potential rotational restrictions, has caused market access concerns for barley and therefore alternative multi-faceted management strategies need to be proven at a local level.

Brome Ryegrass Integrated Management (BRIM) modelling demonstrates sustainable control of brome requires a multi-year approach. Whilst these modelling scenarios show there are gains to be made through current knowledge and thus localised research and demonstration is important(Output 2), and communications is critical (Output 3), there is still a need for research into potential new innovative control tactics (Output 1) given limitations by midazolinone herbicide use and the long period required to drive down brome grass seedbanks.

Project Outcome By May 2027, the economic impact of brome grass will be reduced by 10% across the low rainfall zones of the Western and Southern Regions through the implementation of specific integrated weed management strategies.