WIDESPREAD across most of Victoria, wild oats are a common weed of cereal crops, pastures, roadsides and waste places, including the margins of swamps, lakes and streams.
The Mallee – like most Victorian cropping areas – is confronted with weed challenges every year and one of the most endemic is wild oats.
Wild oat species have lifecycles and growth patterns similar to those of winter cereals, making them highly competitive with crops in the absence of effective control measures.
Most growers – and agronomists – have their own theories on the best way to make the Mallee wild oat proof.
Now, if you have a theory about how to manage weedy or black oats (Avena spp), you can put it to the test on your computer before spending any of your hard-earned money.
Weeds researcher Dr Michael Walsh said the newly released Avena Integrated Management (AIM) model allowed growers and agronomists to test the effects of various wild oat management scenarios applied during a crop rotation on weed population dynamics and crop gross margins.
“AIM predicts the effect on crop yield, emerged weed numbers, weed seedbank and gross margins for each management scenario tested,” he said.
“Users can then test multiple scenarios with different crop rotations and management strategies to compare the impact of these different options.
“Then they can implement the strategy that best suits their farm and business.”
Dr Walsh described AIM as a great way of comparing the longer-term impact of different single and multiple control techniques.
He said AIM was the newest in a suite of similar tools, all based on the widely tried-and-tested RIM model for annual ryegrass management. Similar models were available for brome grass, barnyard grass and barley grass.
“The AIM model was rigorously tested against real-world data collected in a wheat and sorghum cropping rotation trial,” he said.
“The model reliably predicted the effectiveness of both individual and integrated weed management tactics on a wild oat population.”
AIM does not predict herbicide resistance evolution, but existing (or expected) resistance can be simulated by changing the efficacy rating of a particular herbicide during the scenario rotation.
It models scenarios across a 10-year period, with options for various crop species and fallow or pasture phases in a rotation. The available crops are wheat, chickpeas, canola, faba beans, another legume, sorghum, winter fallow, and pasture (sheep grazing).
The AIM model can be downloaded from the Australian Herbicide Resistance Initiative website.
