Control of barley grass in a pasture-barley-oats rotation

Full description

Barley grass is becoming an increasingly problematic weed in Western Australia. A GRDC funded project sought to increase the adoption of integrated weed management tactics for barley grass, by working with grower groups to develop regionally appropriate rotations for optimal control.
A survey indicated that growers in the southern lakes region of Western Australia often had pasture as the main rotation choice after cereal. In contrast to other areas of the wheat belt, some growers in this region considered barley grass a valuable (early) feed in pasture as well as a weed in crops. However, growers found that barley grass could have a large impact on crop yield. Growers were interested in either controlling barley grass or suppressing barley grass in crops while allowing it to survive in pasture.
Most group members felt their barley grass was resistant to herbicides (especially low-level resistance to Group A, Targa®). However, growers were unwilling to stop using Targa®, even if efficiency was reduced against barley grass, as it effectively controlled other grass weeds. Growers wanted to pair Targa® with other products in the pasture to kill barley grass, and then control surviving barley grass in crop with best practice pre-seeding herbicides.
The trial aimed to investigate pasture barley grass control in 2019, pre-emergent herbicides in barley in 2020 and oats in 2021.