The yield results are in for the 2016 liming and deep ripping trial funded by Wheatbelt NRM and conducted by Merredin and District Farm Improvement Grup (MADFIG) and Joel Andrew (Map IQ).
The randomised and replicated trial took place on Andrew Crook’s property just south of Merredin where coastal limes and treatments at various rates (2, 4 & 6 t/ha coastal lime) were compared to a local lime treatment (13 t/ha) in conjunction with deep ripping (with and without). The harvest results have shown that treatments where deep ripping was done after lime application had the highest yield increases. Deep ripping alone was still a major driver for increased yield, but surface application of lime without deep ripping showed no increase in yield - a not so rapid return on investment.
| Method | Indicative Average Yield Results |
|
Surface applied lime had no impact on yield |
1.54 t/ha (equalled control plot yields) |
|
Deep ripping only, no lime applied |
1.86 t/ha (17% increase in yield) |
|
Lime applications followed by deep ripping |
2.01 t/ha (23% increase in yield) |
Very interestingly, the local lime source (at 13t/ha) performed well, yieding the same as the coastal lime treatment at 6 t/ha when both treatments were followed by deep ripping. These results indicate that the use of locally sourced lime may be a viable alternative to coastal lime for the Eastern Wheatbelt growers. Further Whealtbelt NRM funded research with varied rates and sources of local lime will be trialled in 2017 again with MADFIG and Map IQ.
Acknowledgments go to Andrew Crook, Map IQ, Rules Lime Sand, Spreadit and DAFWA for assistance with the 2016 trial.