The Department of Primary Industries and Regional Development (DPIRD) is leading the ‘Nutrient re-distribution and availability in ameliorated and cultivated soils in the Western Region’ project, announced earlier this year by the Grains Research and Development Corporation, which was also discussed in last quarters SoilsWest newsletter. The Department is also working with the University of Western Australia (UWA), Curtin University, Murdoch University, CSIRO and MapIQ to deliver the project. The field trials for this project are now underway at various sites across the state. The feature image shows DPIRD research officer Dr Craig Scanlan and a delegation of Australia’s leading soil scientists discussing the trial at Meckering.

Department plant nutritionist Dr. Craig Scanlan said “that the field trials established this year would help researchers gain a better understanding of the long-term effect of rotary spading and deep ripping on soil nutrient availability and the impact on yield responses to fertiliser. Specifically, the trial at Meckering will provide us with a better understanding of how deep ripping changes the yield response to nitrogen (N) applied this year and if it has any impact on the residual benefit of this N in 2019”.

Dr. Scanlan also advised “that another trial established at the department’s Badgingarra Research Facility has been designed to measure the effect of the type of crop residue buried by inversion tillage in 2019 on the grain yield response to nitrogen fertiliser. Further paddock scale wheat trials have also been set up this season to gain an insight into how the yield response to potassium (K) fertiliser varies spatially on ameliorated soils”.

The trials at Mingenew, Meckering and Esperance are being undertaken on paddocks where Controlled Traffic Farming (CTF) is being used. These paddocks are like massive field trials, where CTF is being used to accurately place the fertiliser treatments and measure the corresponding yield data.

Stephen Davies?

Image: Crop sown using precision guidance into previous stubble (Stephen Davies, DPIRD)

The variation in the yield response to the potassium treatments across the paddocks will be used to target areas for soil sampling, to investigate which soil factors are influencing the yield response to K fertiliser on ameliorated soils. As a result of this work, the department will be able to provide some guidance on how growers should be doing their soil testing on ameliorated soils.

The department’s research complements two other projects, one led by UWA on increasing profits from fertiliser inputs in a range of emerging crop sequences and the other by the CSIRO to improve soil sampling methods to better predict soil nutrient availability and supply. Together, the research projects will quantify how yield response to fertilisers in ameliorated soils compared to current no-till practice. The outcomes of this work will be used to update existing decision support systems for fertiliser use. For more information on the research work contact Dr Craig Scanlan.