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.”

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Saturday, June 6, 2020