Western Australia
May 15, 2014
The incorporation of lime appears to be paying off for some farmers through increased production, and research is underway this season to explore the economics of ameliorating subsoils in the eastern central grainbelt of Western Australia.
One-year projects to determine economic rates and incorporation methods for lime in this region are being funded by the Grains Research and Development Corporation (GRDC) and conducted by Tek Ag at Koorda, and Synergy Consulting at Nungarin.
The GRDC’s Kwinana East Regional Cropping Solutions Network (RCSN) identified the need for locally based trials to provide confidence that certain rates of application and practices will work on eastern central grainbelt farms.
Tek Ag Director/Agronomist Tyrone Henning says Wodjil sandy loams at the Koorda site have good characteristics for water holding capacity and nutrient exchange, so they don’t suffer from non-wetting and leaching, but there are production constraints from low pH and high aluminium concentration.
“We’re aiming to provide growers with information to help them determine how much ameliorant should be applied, what the impact will be on their soil pH, what type of machine would be best to incorporate it, and how much that will cost them,” he said.
“A lot of farming operations in the eastern grainbelt don’t have the equity needed for more expensive treatments like spading and mouldboard ploughing, whereas one-way ploughs, deep rippers, off set discs and full cut cultivators are often already available on-farm or can be hired at a reasonable price.
“We’re therefore assessing the economic returns of each of these combinations, so farmers can start increasing productivity and profitability.”
Growers in the area applying 3-5 tonnes per hectare of applied lime are seeing topsoil pH of 5.5-6.6 in CaCl, but their subsoils are still below 4.4.
“This makes mechanical tilling vital to ameliorate the subsoil, to raise the pH and drop aluminium out of solution,” Mr Henning said.
“Our trials will involve varying rates of lime and different methods of incorporation, and take into account effectiveness of amelioration, cost of lime incorporation, yield per treatment, weed stimulus and the end of the day profit/loss per treatment.
“Our ultimate aim is to help growers manage soils to improve pH levels in a low cost manner, to improve long term profitability to growers in the eastern central grainbelt of WA.”
Mr Henning has produced a video captured from an unmanned aerial vehicle (UAV), showing the work and the parameters of the trial at Koorda. It is available on YouTube at http://youtu.be/egZnu55tks8
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