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Free N Farming - Sustainable farming, Secure future

Free N Farming logo“Free N Farming” refers to the process of harnessing nitrogen fixation from the legume symbiosis with nodule bacteria, and directing this “free” nitrogen into Agricultural systems. This unique symbiosis takes N2 gas from the air and turns it into a form that plants can directly utilise. Until relatively recently in human history, this process has been the primary source of nitrogen in Agriculture. The common availability and ease of application of inorganic N in the 21st Century, derived from the Haber-Bosch process, has overtaken legume N applied in agricultural settings.

It is the VISION of the Centre for Rhizobium Studies (CRS) at Murdoch University to reverse this trend, as Haber-Bosch N is environmentally damaging, and directly expensive.

The current vehicle for implementing this vision is the MLA / AWI funded project “Pasture legumes in the mixed farming zones of WA and NSW: shifting the baseline”.

Case studies in recent years have highlighted how adoption of well adapted pasture legumes and inoculants developed specifically for WA conditions have allowed some farmers to greatly reduce their dependence on fertiliser N.

A simple example is where eight tonnes of legume biomass produced over the winter contains 240 kg of N, equivalent to 500kg of Urea. This “free N” becomes available to rotational cereal or canola crops over the next several seasons. To produce 500 kg of Urea through the Haber-Bosch process would require the combustion of 500kg of fossil fuels, with the attendant release of many tonnes of CO2 into the atmosphere.

Our research over the next decade at CRS will be applied within the guiding principle of “Free N Farming”.

Prof John Howieson
Centre for Rhizobium Studies, Murdoch University
September 2013