Brome grass is the costliest weed to grain production in the Mallee region despite herbicide resistance being relatively low. This paper brings together research trials from 2015 and 2016 addressing the potential for greater efficacy of pre-emergence herbicides on brome and the potential for better crop competition on non-wetting sands. For growers looking to often seed earlier and reduce reliance on Group B herbicides, pre-emergence herbicides can be an important part of brome management strategies but trifluralin often has limited efficacy. Previous trials at the MSF Karoonda site looking at a range of pre-emergence herbicides have shown the potential for greater than 75% brome control, but also the potential for variability under different early-season conditions. Improving crop competition can greatly improve herbicide efficacy. Other trials on non-wetting sandy soil at the Karoonda site have shown the potential for better crop establishment and large reductions in brome seed set suppression through seeding the crop on or near last year’s crop row (e.g. McBeath et al 2015). In 2016 the interactions between pre-emergence herbicide options and crop row placement were investigated.

• Substantially better brome control and seed set reduction is possible by using pre-emergence options other than trifluralin.
• The costly Sakura+Avadex treatment is likely to be the most effective.
• Consistency of performance of all pre-emergence herbicides for brome remains a problem
• On-row seeding on non-wetting sand showed that it can substantially improve early crop emergence.
• One reason for this is the likely wetter surface soil in rows at time of seeding.
• Seasonal conditions such as the long-wet season of 2016 will affect efficacy of both pre-emergence herbicides and the impact of additional crop competition on brome seed set suppression.
• Maintaining low seedbanks and having alternative options for weed seed control when faced with a risk of ‘blowouts’ in brome seed set is important given the chance of particularly poor control in some seasons.