Following our involvement in the GRDC funded project on managing micronutrients in Western Australia, we will continue to collaborate with leading research organisations in recently funded projects to improve our understanding of nutrient requirements and increase profit from nitrogen (N), phosphorus (P) and potassium (K) fertiliser inputs.

There were no responses to nitrogen (N) or potassium (K) in this GRDC funded trial with the Liebe Group last year. The paddock was rotary spaded in 2015 and the trial will be planted to canola this year.

A lot has changed in our cropping systems. Practices such as no-till, earlier sowing, increased canola and reduced legume plantings has changed the supply and availability of nutrients to our crops.  We are also seeing more change with the adoption of deep cultivation to overcome soil physical constraints such as non-wetting and compaction.

Questions around how we should be soil sampling and the effect of deep cultivation on fertiliser requirements will be tackled, but the main project supported by CSBP will focus on increasing profit from N, P and K fertilisers.

For each of the next four years, CSBP will be planting and managing five P trials and one K response trial. The P trials will enable a review of critical values and evaluation of new tests such as DGT P. Two of these trials will be on forest gravels at Williams and Kojonup. K trials will compare the requirements of different crops and the effects of different rotations, while also assessing the residual value of K applications. This year, CSBP will be comparing the K requirements of canola to wheat at Gnowangerup, and next year the residual responses following both crops.

In separately funded GRDC projects managed by the Liebe Group, CSBP will be contributing expertise and in kind support for research into (1) N and K requirements on paddocks ameliorated by deep cultivation, and (2) the need for micronutrients in a low rainfall environment.

Trials relating to the first project were established last year at Mingenew, Eneabba, and Marchagee. Seasonal conditions limited crop yields and responses last year but the sites will be re-cropped this year to lupins, canola and wheat.

A significant portion of the GRDC investment into the micronutrient project will be directed to a plant testing survey to determine the extent of trace element issues. This will be followed up by trials to compare methods for overcoming deficiencies.

We look forward to contributing to wider efforts towards improving fertiliser decisions in Western Australia. It will be complementary to the knowledge gained from our own extensive field research program.