Barley grass is becoming an increasingly problematic weed in Western Australia. A GRDC funded project sought to increase 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 in southwest Australia, many growers thought their barley grass was resistant to grass selective herbicides and may have developed late germination to avoid pre-seeding herbicides. In this area barley grass was a major problem in pastures, and often in break crops too.

A three year trial aimed to investigate pre-emergent herbicides and autumn tickle in wheat in 2019, pre-emergent herbicides and crop density in barley in 2020 and grass selective herbicides and crop topping in pasture in 2021.

In 2019, herbicides ensured that barley grass density was low throughout the trial.

In spite of good crontrol in 2019, there was high barley grass density in 2020, potentailly from the 2019 seed production and dormant seed bank.

The 2020 use of Intercept^® herbicide reduced barley grass across the whole trial, with higher crop yield following Intercept^® at 500 mL/ha compared to 375mL/ha.