Barley grass at high density reduces crop yield. However, GRDC project UA00156 (Seed bank ecology of emerging weeds) has highlighted that barley grass ecotypes in Western Australia are often short, and are likely to be highly sensitive to crop competition. Initial control with pre-emergent herbicides combined with high seeding rates in cereal crops may be sufficient to control this species.
The trial aims to investigate pre-emergent herbicides and high density crop seeding for barley grass control in a barley-wheat rotation in 2020-2021.
Triflur X® at 2 or 3L/ha provided good initial weed control, resulting in low barley grass density throughout the trial. By August 2020, there were fewer actively growing barley grass plants where Triflur X® was applied at a higher rate, and panicle/seed production was significantly reduced. Intervix® provided excellent control, preventing barley grass seed production.
Increased seeding rate increased crop density, but the reduction to barley grass panicle and seed production was not significant. However, the impact of crop density on barley grass may be significant in 2021.