Weeds

Weeds pose a serious risk for primary producers as they can impact on market access and agricultural production.

In 2006/07, each Western Australian agricultural business spent an average of $29 376 ($341 million total) on weed control (Australian Bureau of Statistics).

Weed control is a shared responsibility between landholders, grower groups, biosecurity groups and the Department of Primary Industries and Regional Development.

To protect WA’s agriculture, the department:

  • works with landholders, grower groups, community groups and biosecurity groups
  • regulates weeds under the Biosecurity and Agriculture Management Act 2007
  • provides a weed identification service
  • provides a predictive simulation tool called weed seed wizard
  • provides information on weed control, crop weeds, regulated/declared plants and herbicides
  • contributes to social science through weedwatcher.

For advice on weeds search our website, the Western Australian Organism List or contact our Pest and Disease Information Service (PaDIS).

For diagnostic services, please contact our Diagnostic Laboratory Services.

Articles

  • Annual ryegrass (Lolium rigidum) is one of the most serious and costly weeds of annual winter cropping systems in southern Australia.

  • In 2021 the Department is conducting over 300 research trials across the state from Kununurra in the north to Esperance in the south.

  • In Western Australia, competition from 7-90 capeweed plants per square metre in a wheat crop can reduce crop yield by 28-44% and net return by 25-76%.

  • Wild radish (Raphanus raphanistrum) is highly competitive in crops and can cause a yield loss of 10-90%.

  • In an integrated weed management program, control of weeds should occur in the fallow, pre-sowing, early post-emergent and in pasture phases.

  • This series of video tutorials has been produced to provide advice about the best ways to monitor and sample crops to diagnose and overcome constraints to crop production.

  • Western Australia has seen major changes to the agronomic system, including a drying climate, more intensive cropping rotations and the widespread adoption of no-till.

  • Management of weeds, disease and nitrogen nutrition are ongoing challenges that limit yield potential.

  • This trial examines the positive impact of crop competition, crop type rotation and the mouldboard plough on weed management.