General news category

Precision move to back manufacturing

category: 
General
Seeding’s over, now for the follow-up rain. That was the topic of discussion between Jennacubbine farmer Darren West (left), his son Dylan, Ag Implements Northam branch manager Luke Siddons and salesman Ted Chester, as they reviewed the performance of Mr West’s new DBS precision seeder recently.

Seeding’s over, now for the follow-up rain. That was the topic of discussion between Jennacubbine farmer Darren West (left), his son Dylan, Ag Implements Northam branch manager Luke Siddons and salesman Ted Chester, as they reviewed the performance of Mr West’s new DBS precision seeder recently.

Jennacubbine farmers Dylan West (left) and his father Darren discuss the performance of the paired row boot which was a specific addition to the DBS because the majority of the West program is growing oats for export hay.

Jennacubbine farmers Dylan West (left) and his father Darren discuss the performance of the paired row boot which was a specific addition to the DBS because the majority of the West program is growing oats for export hay.

By KEN WILSON
JENNACUBBINE farmer Darren West is an avid supporter of WA manufacturers.
So it was an easy decision for him assessing a new seeding bar for this season.
His choice was a DBS precision seeder built by Ausplow at its Naval Base factory.
The D260-46N CTF model was delivered in March by Ag Implements Northam, well before the start of a 1700ha cropping program, the majority of which was oats for export hay.
The model designation translates to a 12.2 metre working width on 260 millimetre spacings designed for controlled traffic farming (CTF). It also is designed with a narrow main frame to negotiate narrow gates.
While Darren has yet to change to CTF, the bar is compatible with his 36.6m boomsprayer.
He started the program on May 5 “into dry dirt” and completed most of the program before waiting for the recent rain (and wind) front to pass before completing the final 250ha of oats and 300ha of wheat on deep ripped sand.
“The bar has done everything I hoped it would do,” he said.
“It didn’t miss a beat in the dry digging to between five and seven inches (125-175mm) without compromising seeding depth and the proof of that was the even germinations.
“We added the paired row boots to the bar because we’re mainly growing oats so we’re achieving a narrower row spacing plus leaving it on for wheat helps with weed competition.
“With about 21 mills for May and June, everything is now up and away.
“And we’ve got 54 mills of summer rain sitting down there which is a good feeling.”
According to Darren, the DBS is built for dry sowing.
“It’s got the weight and it just digs and I was pleasantly surprised we didn’t have any problems with string (from hay bales) wrapping around the tines.”
Darren also praised the quality of components, including the Pro-D tool system which comprises the bolt-less DBS knife blade and adaptor, a new fertilizer boot and fertilizer shield.
All are depth adjustable simply by using a specially-designed hand tool to remove a retaining pin which holds the assembly together.
The hand tool also is used to lock the assembly in place once adjustments are made.
Its newly designed and patented closing tool also is depth adjustable using a hand tool.
“It’s a great idea because we basically have two options to use to cater for soil types,” Darren said. “Basically we can dig between five and seven inches on our heavy country and change to seven to nine inches (225mm) for lighter soils if we want to.
“But the hand tool is still in the plastic bag as we had no need to change any points this seeding.”
As far as Darren is concerned the DBS is “the best you can buy” and “it’s built in WA”.
“I’m impressed with the company’s attitude of wanting my feedback to improve the bar and the after sales services both from the company and Ag Implements,” he said. “Having everything local is really good in terms of quick responses from the company and the dealership.”
This year Ausplow improved the Pro D system with a new V2 closing tool assembly and extended-wear fertilizer shield and boot, allowing for precision granular and liquid delivery.
There’s also a V4 tine assembly with stainless steel fertilizer and seeding tubes for improved handling of mud and sticky clays, new stainless steel liquid delivery manifolds with Friction Flow tubing and stainless steel primary risers.
The top rail of the DBS frame is now 100 x 100mm (previously 100 x 50mm) which enhances strength characteristics by nearly 50 per cent with increased gussets and struts within the frame and new gusseting on the wheel arms. The drawbars also have been strengthened.
p Darren also is a member of the Legislative Council representing the Labor Party. He is currently Parliamentary Secretary to the Minister for Regional Development; Agriculture and Food; Ports; Minister assisting the Minister for State Development, Jobs and Trade.
Story and photos courtesy Farm Weekly.

Pot of gold awaits DBS owner

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General

This striking photograph was taken by a DBS customer during seeding, with the comment that he had struck a “pot of gold” using his DBS to establish his crop.
Ausplow has received many comments from owners who have reiterated the performance of the precision seeder, particularly in dry sowing conditions.
In fact much of this year’s program was established dry before the beneficial June rains. With many owners reporting good subsoil moisture there is plenty of confidence going forward.

It’s a wrap for Ausplow 2020 trial establishment

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General
Ausplow R&D coordinator Dr Margaret Roper (left), Quairading farmer Brayden Hayes, nutrient consultant Dave Seagreen and Ausplow engineer Cony Sumoro discuss the Ausplow 2020 trial program after Brayden assisted with the trial work earlier this month pulling the Ausplow trial planter with his Case IH FWA tractor.

Ausplow R&D coordinator Dr Margaret Roper (left), Quairading farmer Brayden Hayes, nutrient consultant Dave Seagreen and Ausplow engineer Cony Sumoro discuss the Ausplow 2020 trial program after Brayden assisted with the trial work earlier this month pulling the Ausplow trial planter with his Case IH FWA tractor.

Quairading farmer Brayden Hayes swings his tractor linked to Ausplow’s trial seeder for one of the final legs of the trial program at Ausplow research and development site at Quairading.

Quairading farmer Brayden Hayes swings his tractor linked to Ausplow’s trial seeder for one of the final legs of the trial program at Ausplow research and development site at Quairading.

Ausplow’s 2020 trial program has been successfully established at the company’s research and development site at Quairading.
The final trials were established earlier this month ahead of good soaking rains in recent weeks.
The on-going program involves liquid fertilisers with the focus this year on assessing nutrient combinations.
These will include a specially-developed Ausplow formulation, designed by the company’s R&D coordinator and microbiologist Dr Margaret Roper and nutrient consultant Dave Seagreen.
All the treatments in the trial will involve near-row sowing.
Already uniform germinations are appearing and hopes are high for a good season to evaluate the potential of treatments.

An important pathway to progressing soil structure

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General
A specially-designed Ausplow DBS precision planter being used in New South Wales. The DBS is a Clayton's version of deep ripping and a defacto Keyline system, encouraging rain to stay where it falls.

A specially-designed Ausplow DBS precision planter being used in New South Wales. The DBS is a Clayton's version of deep ripping and a defacto Keyline system, encouraging rain to stay where it falls.

(PART TWO OF A THREE PART SERIES)
By JOHN RYAN AM
I often wonder what my uncle Percival Yeomans (PA), an engineer and farmer in New South Wales, would say about modern day crop establishment practices.
He was, of course, the inventor of the Keyline contour system which basically was designed to retain moisture where it fell, eliminating washaways and water erosion on slopes and reducing water-logging in the valleys.
It came after he had been experimenting with various tillage techniques for pasture establishment and regeneration in the early 1950s.
Initial attempts started with a chisel plough designed by Texan farmer Graham Hoeme and named after him.
But Percival soon found the two inch wide shanks tore a lot of roots out of the soil while requiring a lot of horsepower to pull it.
Further investigation led him to develop his own plough, called the Yeomans plough, which was used for keyline plowing when he established ‘The Keyline Plan’ in 1954.
It was essentially designed, with thinner shanks, to lift and aerate the soil while limiting soil disturbance to minimize oxidation of organic matter.
For many years the Yeomans plough became the tillage tool for deep tilling and pasture renovation but the lack of high horsepower tractors limited its ability to work deep in the subsoil.
Further development was based on work in Texas with a ‘Lubbock Vibrating Plow’ which was designed with a vibration mechanism, driven off the tractor PTO.
It featured a dual eccentric counter-balanced rotor system which acted as a unbalanced flywheel.
As the flywheel turned, it caused the entire implement to vibrate and the machine was made out of angle iron and bolted together rather than welded to withstand the vibrations.
Its most important feature was that it broke up hardpans, yet left the soil relatively undisturbed.
In the early 1970s I began developing a similar machine which was later called the Shakeaerator, which was in commercial production between 1974 and 1979 and was manufactured under licence in England.
It was able to penetrate deeper into the subsoil and used less horsepower than the chisel plough which was restricted by a spring-loaded tine and a C-shank, which increased horsepower requirements.
The Shakeaerator worked better in dry, hard soils which resulted in good fracturing but very high wearing parts.
It led to farmers reverting to the chisel plough again with a lot of work often done after rainfall events.
This led to soil collapsing, causing re-compaction and losing soil aggregation or structure which plant roots couldn’t penetrate to obtain deeper moisture and nutrients.
It was found that ripping into established pasture, or after seeding with roots established, maintained soil aggregation, allowing good infiltration of moisture and easier access for plant roots to grow deeper in the subsoil.
My experience was that ripping at seeding allowed plants to develop roots quicker which reduced soil collapsing to maintain good infiltration of moisture and air.
It was the right idea but it proved difficult to obtain accurate seed placement as seed often fell into the deeper furrow created by the digging blades.
That’s when I started to develop the DBS no-till system, which in effect, is a Clayton’s version of deep tilling – loosening the soil, aerating it, providing moisture infiltration and achieving accurate seed placement.
It also is a defacto Keyline system encouraging rain to stay where it falls – how many DBS owners have trouble filling their dams?
So now we’ve arrived at our next development. We’ll continue the story in our September edition of Ausfacts.

Ausplow trials enter second phase

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General

Ausplow’s on-going research and development program involving liquid fertilisers at its Quairading research and development centre has entered its second phase.
Following last year’s trial of 10 treatments, held in a difficult season with statistically inconclusive results, this year’s trial which was established in May, will focus on assessing nutrient combinations.
These will include a specially-developed Ausplow formulation, designed by the company’s R&D coordinator and microbiologist Dr Margaret Roper (pictured above) and nutrient consultant Dave Seagreen.
All the treatments in the trial will involve near-row sowing.
According to Dr Roper, the focus of the trial is on “proving the hypothesis that the new liquid fertilisers perform better than current standard fertiliser strategies in a near-row sowing system”.
While working as a principal research scientist at CSIRO, Dr Roper was engaged in research trials that showed near-row sowing overcame the problems of establishing crops in non-wetting soils.
“This is further enhanced with the DBS system,” Dr Roper said. “Essentially the three-slot system creates an environment that improves plant germination, particularly in dry-sowing scenarios in water-repellent soils.
“We are seeing an increase in dry sowing, particularly as farmers are starting seeding programs earlier sowing canola.
“Our hypothesis is that in near-row sowing, the DBS maintains a relative humidity environment that allows dry seeding at the paddock scale by creating a wet seeding environment at the seedling scale.
“This is because, in water-repellent soils, water enters the soil via old root pathways and therefore, near-row sowing together with liquid fertilisers creates a relative humidity that is near 100 per cent, or at saturation point of water vapour surrounding the seed.
“This is a real eye-opener for us as we better understand how the DBS creates this environment allowing water vapour to be a primary source of moisture for seeds.
“If our hypothesis proves to be correct, the combination of liquid fertilisers and near-row sowing will greatly mitigate the negative impacts of dry sowing, reducing or eliminating staggered plant germinations typical of water-repellent soils.
“I am very excited by our initial trial work and I believe the new Ausplow nutrient formulation is a key to the overall success of our research.”

Patience the big message to building healthy soils

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General

Glenn Innes, NSW, farmers Greg and Sally Chappell are reaping the rewards of a patient endeavour to improve soil health on their Shannon Vale property.
But the latest message from the couple, who also run Dulverton Angus stud, is that they’ve got more to do.
The couple oversee 500 cows on their home property with 150 bulls, with a further 400 cows on a neighbouring lease block.
The Shannon Vale property totals 3600 acres (1450ha) and when the Chappells bought property in 2001, it was immediately apparent a strategy was needed to overcome a long history of degraded and compacted soils.
With an annual rainfall of 875mm (35in), it was imperative to take advantage of the available moisture and so began a program to improve the soil’s water-holding capacity by building up carbon levels.
Weeds were the main problem, particularly African lovegrass, which had negligible nutritional value yet dominated over more palatable pasture species.
“Since about 2008, we have been re-building the soil by increasing organic and carbon content, through things like mulching weeds, manuring and using a liquid potassium mix, based on plant analysis,” Greg said.
The herd becomes the mechanised process of smashing up weed ‘stubble’, including lovegrass, bringing it in contact with the soil where biological processes start material decomposition.
“It’s a long-term process but we’re seeing encouraging signs from our measuring sites,” Greg said.
“When we started we were below one for organic carbon and now it’s around 3.5.
“With soil pH it’s gone between 4.4 and 5.7 to 5.9 and 7.1.
“And now, none of the sites are measuring below 5.7.”
His explanation for the change, after a period of only four years, was simple: “We stopped single super (too much acid) and started manuring.
In 2017 Greg established 84 acres (34ha) of pasture with an Ausplow DBS trial planter, using a balanced granular formula to plant ryegrass and Lucerne.
Greg was impressed with the result, particularly the under-seed cultivation and shattering of the subsoil, breaking up soil hardpans and encouraging water infiltration.
On the pasture renovation side, Greg says by using the DBS and Multistream they are accelerating the process he and Sally started, because, “we didn’t factor in this type of deep tillage in the beginning”.
“And we’ve introduced dung beetles to get those cow pads into the soil to bring up the carbon levels and we’re creating a worm environment,” he said.
Greg has also used the DBS planter to establish forage sorghum and cow pea (for N in the silage), which is used as silage feed for the cattle.
Last year he bought a 15-foot (4.5m) DBS on 10-inch (25cm) spacings with a mounted Multistream on the bar and liquid tanks on the drawbar to provide him with the capacity to switch between granular applications and liquids, including a new Ausplow formulation.
Now he is looking at replacing the granular fertiliser box with a liquid tank to go “full liquid”.
“The liquids give us a chance to move forward with a balanced nutrition package being introduced into the soil, providing more benefit for high performance pasture growth,” he said.
“The liquids are doing a far superior job for us with quicker germinations and plant growth that outcompetes the weeds.
“For us, the DBS is our pasture renovator and it is working really well.
“Ausplow also added twin Turbo discs out front to cut the plant roots without disturbing the main tap root.
“The discs are the duck’s nuts especially in lovegrass which is very clumpy.
“We’re sowing oats into it with the idea of busting up the subsoil to get a more permanent pasture with a diverse plant mix.
“I like the DBS because it is a one-pass operation.
“You’re keeping soil intact in these grey loams and building healthy soils because of the minimal disturbance and the root build-up which creates air spaces and pathways for moisture.
“It will take time but we’re retaining organic carbon and building moisture-holding soil.
“This in turn will improve the cation exchange capacity (CEC) which in our sandy soils is low, so we have no binding structure.
“By improving organic matter and holding water in the root zone, we achieve a higher CEC, which influences the soil’s ability to hold onto essential nutrients and make them available to plants.”

Managing change in a marginal area

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General
Bencubbin farmer Nick Gillett has two 60-foot DBS precision seeders for his 10,000-hectare cropping program to ensure he completes his program within the ideal sowing window, which he says gives him the ability to get the crop in and up in marginal moisture conditions.

Bencubbin farmer Nick Gillett has two 60-foot DBS precision seeders for his 10,000-hectare cropping program to ensure he completes his program within the ideal sowing window, which he says gives him the ability to get the crop in and up in marginal moisture conditions.

Managing change is arguably the number one challenge for farmers these days.
And for WA farmer Nick Gillett, who manages an 10,000-hectare cropping program at Bencubbin (275km north east of Perth), it’s the reason he has two 60-foot DBS precision seeders.
“In a nutshell, it gives me the ability to get crop in and up in marginal moisture conditions,” he said.
But timing also plays an important role and Nick has noticed the seasons are getting shorter(dry warm finish, etc).
“Basically 2014 was an extremely tough finish and crop-s sown later than mid-May didn’t perform well,” he said.
“This was the primary reason for going from a 50-ft to 60ft DBS in 2015. Seasons have always been changing, however, 2014 stood out.
“Frost is always a concern but sometimes our last seeded crops are the worst affected,” Nick said. “So it’s hard to farm for frost and you’ve got to stick with yield is king.
“It’s better to set up a potential two tonne crop with the risk of some frost than a 1.4t crop potential and not getting any frost.”
It’s a similar attitude to liquids and near-row sowing.
This year Nick is returning to trialling liquids again, in his marginal area with about 310mm of average rainfall.
“We started with Flexi-N in 2000 and basically did it until 2015,” he said.
“We stopped simply because of the cost differential between Flexi-N and granulated urea, the ease of operator use and the variability of zinc and Flutriafol (fungicide).
“With the latter we were getting build-up inside the nozzle body and sometimes a skin across the filters.
“We found poor tank mix compatibility and it added another complexity level for the operator to check componentry and keep an eye on pressures.”
Nick has two 6000 litre capacity liquid carts to provide a bigger capacity outside of his air seeders and with the acquisition of his second 60-foot DBS, with Friction Flow liquid kit, he hopes he will have time to “play around a bit” with liquid nutrition.
“I think it’s time to go back to liquids but it still depends on the pricing spread between urea and Flexi-N,” he said.
With near-row sowing, Nick says inter-row sowing with RTK has been his management practice since 2006.
“If we’re chasing moisture to get a germination we more often go on-row because our stubble levels aren’t too high,” he said. “But our main aim is to sow in between the rows and maintain our standing stubble.
“On-row is probably less than five per cent of our program and is mainly a tool for the heavier clay type soils where germination can be an issue with small amounts of rain.”
“I know non-wetting can be an issue sowing inter-row but it’s not an issue here because of our soil types and rotations.
“We mostly have Mallee soils running into Salmon Gum clay loams to deeper sands and gravels.
Nick maintains a watchful eye on changes.
“The game changes every year and you try to make little increments of change because it is still hard to know if you’re doing everything correctly,” he said.
“We have proven recipes but the problem is utilising the best recipe for a given season.
“I think the best tools are timeliness and attention to detail."

Where are the new strategies?

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General
While the majority of current research focuses on soil amelioration techniques, Ausplow's fopcus is on a sustainable approach, through our 'pot plant' crop establishment techniques.

While the majority of current research focuses on soil amelioration techniques, Ausplow's fopcus is on a sustainable approach, through our 'pot plant' crop establishment techniques.

(PART ONE OF A THREE-PART SERIES)

By John Ryan AM
It has been an interesting few months for me as I have reviewed a lot of stories relating to increasing crop yields.
Soil amelioration is obviously the number one topic at the moment whether it’s using mouldboard ploughs, one-way ploughs, spading, offset discs or deep ripping, to work clay, dolomite, lime, gypsum or a number of other ameliorants and topsoil, into the subsoil.
There can be various strategies for ameliorating soil, from overcoming non-wetting, to burying herbicide-resistant weed seeds, to increasing topsoil pH, etc.
And the hope is that whichever strategy you use, you’re improving the soil and therefore on your way to increasing crop yields, with the promise, mainly from researchers, of residual benefits that could last up to five years or more.
A lot of the focus on amelioration is on Western Australia and South Australia’s non-wetting, sandy soils, with the main methods used in SA being delving and clay spreading.
In other parts of the national Wheatbelt, trials have been established by various researchers exploring the use of deep ripping to apply soil amendments such as a leguminous green manure, chicken litter, cereal stubble and gypsum.
Researchers are also monitoring 15 existing long-term trials to help gauge the residual effects, especially the cost-benefits, of soil amelioration in South Australia, Victoria, NSW and Tasmania.
So as we progress through 2020 it is fairly evident researchers are all rowing the same way.
Which leads us to the direction we are taking.
We’ve actually spelt it out in previous editions of Ausfacts that our focus is a sustainable approach, through our ‘pot plant’ crop establishment techniques, with the emphasis on improving soil while making money.
And we’ve been encouraged by our initial trials results from last year at our Quairading research and development centre and by the work being done by our R&D coordinator Dr Margaret Roper (More of her research is published in our What’s New section of our Web page, October 26, 2019).
Margaret and a team of CSIRO researchers have recently released a paper based on 12 years research which is worth reading January 18, 2020).
Again you can access the information on our Web page in our ‘What’s New’ section.
The story has the heading: Is cultivation really the bogeyman of crop establishment?
In our next Ausfacts issue I’ll explain how this story ties in with what we are doing with the DBS.
I would also encourage you to ask your local DBS dealer for a free copy of our book called The Genius of Farmers.
In the meantime, if you are interested in setting up a few trials this year similar to what we are doing at Quairading (see the January edition of Ausfacts), please feel free to contact me at john@ausplowcom.au

2020 a focus on liquid nutrients

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General
Cranbrook farmer Theo Cunningham (left), talks with Ausplow consultant Dr Margaret Roper, Ausplow General Manager Chris Farmer and Managing Director John Ryan AM in a freshly-harvested crop of Planet barley to examine the closeness of the roots to the previous year’s row.

Cranbrook farmer Theo Cunningham (left), talks with Ausplow consultant Dr Margaret Roper, Ausplow General Manager Chris Farmer and Managing Director John Ryan AM in a freshly-harvested crop of Planet barley to examine the closeness of the roots to the previous year’s row.

As we move into a new year, our focus remains on continuing a comprehensive research and development program.
It will be spearheaded by our liquid nutrient trials on our Quairading trial site which have produced promising results from 2019 in a difficult ‘moisture-deprived’ year.
We also will expand trials associated with near-furrow sowing with particular focus on how Cranbrook farmer Theo Cunningham fares with his move this year to maintain the DBS pot plant furrows.
Theo has been one of the early adopters of near-row sowing in 2018 using the ProTrakker guidance hitch attached to his 46 foot (13.9 metres) DBS precision seeder for the past two years. In studying the system, he saw that moving 25mm to the right every year meant an incremental shift away from the original ‘pot plant’ and the inherent nutrients.
So this year he will try a 20mm shift to the left of the furrow and begin an alternating left-right pattern of near-row crop establishment every year, basically maintaining the integrity of the ‘pot plant’.
The ProTrakker was bought in 2015 from WA distributor Burando Hill and after four seasons of use,
Theo says the theory of the benefits of near-row sowing is now solid fact.
“It has given us the ability to establish crops every year during the optimum growing window while minimising the risk of establishment because we’re overcoming non-wetting issues,” he said.
“That gives plants the chance to achieve their yield potential.
“Our average crop yields are slowly creeping up but the best thing is that we are now more confident in our expectations of reliably achieving 1.8 tonnes (a hectare) with canola, three tonnes with wheat and 3.5t/ha with barley.
“These have become realistic figures for our annual budgets.”
In 2019 he established his cereal crops with 50 litres of Flexi-N applied with the seed with Impact and used 1.5L/ha of surfactant SE14, a deep-banded moisture retaining agent.
“We used the SE14 as a risk-aversion tool because even using the ProTrakker you can’t guarantee you’ll sow exactly onto the old root furrow,” Theo said.
“So it’s a bit of insurance to make sure the seed gets away and the roots go straight down if not in, but near the old root furrow.
“The other advantage of using the same row and not disturbing stubbles is that the stubbles act like moisture conduits directing water into the furrow.”
One of Theo’s concerns is the possible increase in diseases but Ausplow trial co-ordinator and micro-biologist Dr Margaret Roper says disease incidence in near-row trials at Munglinup over seven years showed minimal presence.
“It (disease) certainly needs a proper evaluation but our trials show, in the presence of moisture in the old root pathways, beneficial bacteria can flourish,” she said. “Some of these bacteria have the potential to reduce root diseases.”

Cultivation the bogeyman of crop establishment

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General
Cranbrook farmer Theo Cunningham (left) digs into an old root pathway to examine subsoil. He is being watched by Ausplow research and development coordinator Dr Margaret Roper and Ausplow managing director John Ryan AM.

Cranbrook farmer Theo Cunningham (left) digs into an old root pathway to examine subsoil. He is being watched by Ausplow research and development coordinator Dr Margaret Roper and Ausplow managing director John Ryan AM.

Stubble removed and cultivated prior to seeding. The dye shows the pathways for water movement have been destroyed. Photo courtesy Margaret Roper and Phil Ward, CSIRO.

Stubble removed and cultivated prior to seeding. The dye shows the pathways for water movement have been destroyed. Photo courtesy Margaret Roper and Phil Ward, CSIRO.

Blue dye shows infiltration down new and old rows in a zero-tilled row. Photo courtesy Margaret Roper and Phil Ward, CSIRO.

Blue dye shows infiltration down new and old rows in a zero-tilled row. Photo courtesy Margaret Roper and Phil Ward, CSIRO.

Former CSIRO scientist and microbiologist Dr Margaret Roper … cultivation can reduce organic matter and water-holding capacity in the soil.

Former CSIRO scientist and microbiologist Dr Margaret Roper … cultivation can reduce organic matter and water-holding capacity in the soil.

By KEN WILSON
THERE is no denying that agriculture has experienced a series of paradigm shifts over the past 70 years.
And as technology wraps itself tightly around the industry, more attention is being paid to technological changes such as variable rate product applications, robotic farming, et al.
Technology also has been employed in the form of mouldboard ploughs, spaders and deep rippers to ameliorate WA’s soil water repellency and bury weed seeds - practices we have seen ramped up over the past decade.
But for all that focus, aimed at producing higher-yielding crops (and in some cases pastures), there remains a missing piece to the jigsaw puzzle that is farming.
The missing piece is often referred to but it remains out of sight and mostly, out of mind.
I’m of course referring to bacteria, fungi and small soil animals, otherwise referred to as soil microorganisms or soil microbes. Soil microorganisms are many and diverse and it is estimated there are more than 10 billion microbes in a kilogram of soil.
Soil microbes process organic materials of plant and animal origin into soil organic matter and contribute to soil structure.
They decompose pollutants, are responsible for biological control (including controlling plant diseases), and cycle nutrients in the soil for plant and microbial use.
Soil organic matter significantly increases the water-holding capacity of soils, particularly sandy soils.
There is conjecture, however, about how soil microbes and organic matter are affected by technology but former CSIRO scientist and microbiologist Dr Margaret Roper is in no doubt, on the back of more than a decade of trials: cultivation practices can reduce organic matter and water-holding capacity in our water-repellent sandy soils.
“We have consistently found in trials over the years that cultivation (and stubble burning) will result in the loss of organic matter in the soil,” Dr Roper said.
In the 1980s ‘district practice’ was to burn stubbles before cultivating and seeding, but after a series of severe wind erosion events, no-till with stubble retention was gradually adopted.
In 2008, Dr Roper was involved in a trial program at Munglinup and after four years of measuring organic matter in ‘district practice’ plots, a noticeable depletion in organic matter levels occurred in the top soil down to ten centimetres, compared with no-till plots.
“It happened quite quickly from 2009 onwards,” Dr Roper said. “It was so consistent that we stopped the burning in 2011 but we retained the plots in our overall trial program.
“From 2012 to 2017 we returned all plots to no-till and stubble retention.
“After six years, the plots that were previously burned and cultivated in the first four years of the trial, showed little or no recovery in terms of organic matter levels, water-holding capacity and crop yields when compared with the plots which had been under no-till and stubble-retention from the beginning of the trial.
“It can really take a long time for the soil to recover from burning stubbles.”
Interestingly when the Munglinup trials started, the soil water content was always higher in the more repellent no-till and stubble retained plots than the cultivated and burned plots.
“In the cultivated and burnt treatment, with least repellence water infiltration was less,” Dr Roper said.
“This went against conventional thinking because the more soil organic matter the more waxes are present to make soil more water-repellent.
“Waxes are produced by plants to protect them from loss of water. When plant material decays, waxes are released and coat sand particles and cause repellency.”
The research team of Dr Roper and colleagues Phil Ward, Ramona Kerr and Shayne Micin, discovered, through dye tests, that no-till had preserved the old plant root pathways which allowed water to travel beyond the water-repellent top layer of the root zone.
“It was easy to see in the cultivated and burnt plots that the dye couldn’t penetrate with root pathways destroyed,” Dr Roper said.
Dr Roper and her team continued research into water repellence - and diseases - and in 2011 organised trials involving on-row and inter-row crop establishment in a no-till stubble retention system.
“We had similar results with crops sown into the row and moisture infiltrating old root pathways,” Dr Roper said. “On the inter-row, it was bone dry, even after significant rain.”
This research work has set up the tantalising prospect of establishing crops every year near the previous year’s plant rows (near-row sowing) to continue to build organic matter and create, eventually, paddocks with the capacity to hold water in the topsoil.
Such an effect would mean the proliferation of beneficial bacteria and a healthy soil environment to enhance soil structure and microbial functions.
According to Dr Roper, there is research around the world that shows if you create an environment that increases organic matter, you can achieve a significant increase in available water-holding capacity, and this can be more pronounced in sandier soils.
The problem is getting to that level of soil fertility. It’s not a quick fix.
Having said that, Dr Roper says the trial results at Munglinup showed that improvements in water infiltration are rapid (less than three years) after transitioning from cultivation to no-till due to early development and preservation of new root pathways for water flow, that by-passes repellent surface soil layers.
Conversely, rebuilding soil organic matter and associated water-holding capacity after transitioning from stubble burning to stubble retention, is much slower (greater than six years) and so is the accumulation of crop residue ground cover that protects soils from temperature extremes and conserves soil water.
Understanding how long it takes to restore soil to its optimum fertility remains elusive.
And in an economic environment where every paddock must make money, it’s problematic that any paradigm shift, alluded to here, will occur, particularly with farmers cropping in sandy soils.
But while soil amelioration techniques maybe working, it could be argued that the cost of these techniques warrants a closer look at the cheaper technique of near-row sowing.
Naysayers will quickly point out the disease build-up associated with such a method, but Dr Roper says there is no evidence of diseases associated with the Munglinup trials.
“It (disease) certainly needs a proper evaluation but our trials show, in the presence of moisture in the old root pathways, beneficial bacteria can flourish. Some of these bacteria have the potential to reduce root diseases.
Whether the Munglinup trials will gain broader traction with farmers remains to be seen.
But if the goal is to produce more from existing land holdings, it is arguable that maintaining methods that preserve organic matter and soil structure, are the right way to go.
(Story courtesy FARM WEEKLY).

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