Sodic Soil Management. Increasing profitability in southeast Australian farms

Australian farmers are losing profits and competitive advantage globally due to lost yield and fodder potential because of soil constraints. Farmers can have huge crop and pasture losses caused by waterlogging and hard setting soils in “normal” seasonal conditions which weighs heavily on non-impacted areas to make up lost potential and meet operating expenses.

Australian farmers can improve productivity, profitability, and resilience by understanding their underlying business fundamentals and crafting a strategy to modify management and invest in long term operational amelioration interventions. Overcoming soil constraints needs to be approached holistically as a part of the whole farm management plan as all decisions impact on the resource allocations in other areas. Soil amelioration should not be seen as just the chemical or physical addition or modification but at all farm management levels including crop and pasture selection/rotation, tillage interventions, chemical and fertiliser selection, and integration of livestock.

The detrimental impact of continuous cropping and tillage on Australian soils is increasingly understood and being managed through reduced tillage yet minimum tillage does not go far enough to address bio-physical constraints associated with sodic, dispersive soils. Farmers need to understand the soil and its performance under different seasonal conditions to craft the plans to improve their performance. 

This report provides an outline of the issue, the means of categorising and mapping soils, the various management modification possibilities as well as an understanding of amelioration options including an extensive outline of amelioration machinery options. The report aims to inform farmers facing soil constraints with a greater depth of understanding of the issue and associated tools to overcome them.

Modern sensor technology, digital software and algorithms are now at a point where they can be cost effectively utilised by farmers to categorise soils and understand the performance at a farm, paddock, and individual square meter level. Phytoremediation of soils through well planned crop and pasture selection especially with the use of perennial pastures and managed grazing is critical to managing sodic, dispersive soils. Physical, chemical, and biological constraints associated with sodic, dispersive soils can be overcome with strategic deep placement of organic materials and nutrients.

In the next five years the depth of understanding of soil constraints and their best amelioration options will greatly increase thanks to private and public research active at time of writing.