Breakthrough for dryland farming

Breakthrough for dryland farming

A healthy stand of regenerating biserulla ... a component of a new way of farming developed to boost profit and reduce risk in low and medium rainfall areas of Australia's grainbelt.

A healthy stand of regenerating biserulla ... a component of a new way of farming developed to boost profit and reduce risk in low and medium rainfall areas of Australia's grainbelt.


THE pith of this story is less costs and less risk. The context is dryland farming.


THE pith of this story is less costs and less risk.

The context is dryland farming.

The ‘who-said-so’s’ are some of Australia’s most eminent scientists.

And they’ve got the backing of federal Agriculture Minister Barnaby Joyce, who has approved a $16.6 million funding for a five-year project which has the potential to change the face of Australian dryland farming.

The wordy headline for the project is: Boosting profit and reducing risk of mixed farms in low and medium rainfall areas with newly-discovered legume pastures enabled by innovative management methods.

It is supported by the Grains Research and Development Corporation, Meat and Livestock Australia and Australian Wool Innovation and involves Murdoch University, CSIRO, South Australian Research and Development Institute, Department of Primary Industries and Regional Development, Charles Sturt University and grower groups in five programs – legume selection, cropping systems, livestock systems, economics and farm modelling, and extension and project management.

It’s a big deal and arguably is the vehicle to establish a sustainable and profitable farming system in cost and moisture-challenged regions of Australia’s grainbelt – mainly sandy and sandy/gravel soils.

Typical areas also record annual rainfall between 250 millimetres and 400mm.

The project is impeccably timed and eruditely described by the project’s authors:

“Over the past three decades livestock numbers in Australia have decreased as farmers concentrated on crops,” the authors said.

“Continuously-cropped paddocks are not sustainable and are high risk, especially in dry areas where wheat dominates.

“Intensive cropping is prone to herbicide resistant-weeds, requires large nitrogen fertiliser inputs, and (faces) significant financial shocks when yields are restricted by frost or dry conditions.”

Now there is a perfect storm in favour of farmers – a buoyant livestock market and potential abundance of Australian-bred pasture legumes, importantly with world-leading hard-seeded genotypes, heat-protected rhizobia inoculants, and harvesting with conventional machinery that allows farmers to produce their own seed and establish legume pastures inexpensively.

According to project leader, Professor John Howieson from the Centre for Rhizobium Studies at Murdoch University, the project is a game-changer for Australian broadacre agriculture.

“Modern farming systems are placing greater demands on pastures, especially in low rainfall areas,” he said.

“Depressed meat and wool prices over the past two or three decades have prompted growers to intensify cropping.

“But crops are regularly compromised in this region by drought and frost, and last year in WA, frost reduced farm incomes by 50 per cent in many areas.

“Rotational options other than cereals are limited, and costly fertiliser nitrogen and herbicide inputs are required.

“Cereal intensive rotations result in declined soil carbon and fertility, and given continued climate uncertainty and recent upturns in livestock prices, the long-term sustainability of farming in southern Australia requires a mixed farming system that spreads the risk across multiple enterprises (crops and animals) while reducing inputs (herbicides, fertiliser, labour) leading to greater long-term farm profit.”

Professor Howieson said the genesis of what they were doing, which had been proven in a five-year pilot study they had done with growers and was funded by the MLA, goes back to 1993 when vacuum-harvesting sub clovers was going out the back door, sounding the death knell to clover farming in an era of more intensified cropping.

He said they applied more focus on researching what we called the aerial, or above-ground varieties and set out to develop new species to fit into a new farming system.

“Now with this funding there is momentum for that pasture science which we have been involved with for 30 years,” Professor Howieson said.

“There is a good understanding of the value of clover farming as the backbone of cropping and livestock production but now we can change that to pasture because we have the aerial varieties that perform in large areas of Australia’s grainbelt where production and profit of sub clovers was problematic.

“What we have are nitrogen-fixing varieties that nobody else in the world is developing, like serradellas, biserrulas, bladder clovers and South African species like Lebeckia.

“Trials have shown nitrogen-fixing is equivalent to 400kg/ha of urea, so that’s a huge cost saving when you’re not using bagged nitrogen.

“The varieties also possess deep roots that enable them to tolerate dry periods and grow for longer periods, increasing their water-use efficiency compared to traditional pastures and providing a longer ‘green pick’.

“These legumes will also result in rapid livestock growth while reducing greenhouse gas emissions from ruminants.

“And with improvements in weed and disease management in crops following the pastures, the productivity and water-use efficiency of the whole farming system will be enhanced.”

Professor Howieson said the only way for legumes to survive in Australia’s harsh environments was to be very hard-seeded (dormant) with rhizobium that doesn’t die in summer heat.

“The big thing with these varieties is that they can be sown in late February and early March at a time when summer knockdown spraying has been done and rigs are being looked at again for winter sowing,” he said.

“The hard-seededness dissipates by April to allow germination with autumn rain and new methods of protecting rhizobia have recently been developed for this sowing.

“In the past farmers wouldn’t consider sowing pasture because it didn’t pay but that’s all changed now, with renewed focus on livestock and more desire by farmers to become involved with a mixed farming system that promises sustainability and profit.”

That last word, of course, is probably the main carrot to be used to convince farmers to embrace the project.

“The sheer bulk of material from these varieties is enough to feed stock, provide competition against weeds and fix nitrogen,” Professor Howieson said.

“That means less cost on supplementary feeding during dry spells and fewer sprays to control weed burdens.

“And with fewer sprays, you’re negating, to a large extent, resistance pressures.

“Plus there’s the benefit in soil fertility which is ongoing.

“We’ll probably always be facing a moisture-limited scenario but the big point with pasture is there’s less risk and less cost in growing crops, even in years when frost knocks the bottom line, because you haven’t spent money on nitrogen to the extent you normally would.

“We know costs are a major adoption barrier and this project will focus on inexpensive options.

“Establishing legume pastures are likely to be less than $100/hectare, and in many cases can be amortised over 20 years, because these legumes regenerate on demand.”

Professor Howieson said “regenerate on demand” was the term researchers coined that implies the farmer chooses when to keep the regenerating pasture for feed and nitrogen production.

It could be the year after crop, it could be the second year, or the third year after – depending on what the farmer “demands” in any given year.

What the project promises...

A PILOT project in the medium rainfall zones of WA and southern New South Wales has demonstrated how novel pasture legumes improve livestock production through enhanced growth and reproduction, while dramatically reducing fertiliser and herbicide inputs for following crops.

The new project will discover resilient low-cost pasture legumes with appropriate management packages and promote their adoption over one million hectares in the low and medium rainfall areas of WA, South Australia, Victoria and southern New South Wales.

As a result, according to researchers, average farm profit will be boosted by 10 per cent and economic risk will be halved over a range of seasons.

This will be matched with highly effective rhizobial inoculants to enable farmers to integrate pastures and livestock into crop intensive rotations with minimal cost and effort.

Legumes with suitable hard-seededness will be selected that persist through several years of crop and regenerate ‘on-demand’.

Researchers also say decreasing the cost of cropping by reducing nitrogen and herbicide usage, and spreading the production risk across the animal enterprises, will enhance the resilience of farms to frost and drought and variable weather.

According to project leader, Professor John Howieson, growers will help select the best legumes, quantify their benefits, and develop management techniques to ensure rapid adoption.

He said the extension program would work closely with farmer groups throughout four States and interact directly with at least 3500 growers.

YouTube videos of growers from the pilot program will be promoted to raise awareness at the start of the project.

Extension specialists will collaborate with the promotional departments of Grains Research and Development Corporation, Meat & Livestock Australia and Australian Wool Innovation.

Targeted field days, workshops and publications will boost the knowledge of growers, advisors, input and service providers, and the wider industry, so that they will be confident of the benefits of the novel legumes to farm performance.

In collaboration with grower groups, awareness of the project will be raised through field walks at experimental sites, field days and grower group newsletter articles, at least nine commercial paddock demonstration sites in 2020 and 2021, a fact sheets for each new legume, and cases studies published as YouTube clips.


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