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

  • Herbicide performance can vary greatly depending on a number of factors. These can include compatibility of herbicides, water quality, sprayer decontamination and controlling stressed weeds.

  • The term 'residual' applies to a number of herbicides that have a long lasting activity in the soil. These herbicides are often applied directly to the soil prior to planting crops, pre-emergent.

  • Spray-topping is a very effective method for managing annual grass seed set in pastures.

  • 'Crop-topping' is the late application of herbicides to prevent weed seed-set.

  • Windmill grass (Chloris truncata) is a native species and is the tenth most common summer weed species in the Western Australian wheatbelt.

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

  • Herbicides can be applied by a variety of means including boom sprayers, aerial spraying, misters, blanket wipers, rope wick applicators, weed seekers and back-pack sprayers.

  • Doublegee or spiny emex is a significant weed in Western Australia. It is a vigorous annual herb with a strong tap root and a long, fleshy, hairless stem.

  • Herbicide resistance is the inherited ability of an individual plant to survive a herbicide application that would kill a normal population of the same species.

  • Following the extended dry conditions this autumn, weeds are now emerging and becoming a challenge for growers to manage in paddocks that may have patchy crops, crops with staggered emergence or no