Ripper Gauge - Demonstrating the Impact of Deep Ripping Timing

⁠⁠⁠The Esperance port zone through GRDCs Regional Cropping Solutions Network (RCSN) have identified that their soils have hard pans and compaction that can be ameliorated through deep ripping. Once these soils have been ameliorated controlled traffic farming (CTF) is needed to reduce the long-term impacts of soil constraints such as non-wetting soils, compaction and waterlogging. With approximately 14 million arable hectares in the Western Region of which, 75% has been assessed at risk of lost production due to soil compaction. Compaction is conservatively estimated to cost the industry around $333m annually (Bennett, 2014). In the Albany and Esperance port zones, it is estimated that 80% of cropping land is affected by moderate subsoil compaction, with a 40% chance of incurring a 10% yield penalty in that area (Petersen, 2015). The effects of compaction include reduced water infiltration, which can increase the risk of waterlogging and water erosion of soil. Deep ripping of compacted soils can provide positive responses; however, it is an expensive process with costs of up to $80/ha (Hall, et al., 2009) and there is a risk associated with not doing it correctly. Given the high cost of some of the options to address these constraints, increasing the longevity of their impact will ensure the best return on investment. By addressing more than one constraint in a single operation when applying the mitigation option will increase profitability.

The Lakes District and Ravensthorpe areas was discussed at the Esperance port zone RCSN meeting with members wanting to have a greater understanding of which soils in that region are responsive to ripping, and then how to best maintain the longevity of these treatments post amelioration. Soil types vary widely across the Esperance port zone that understanding how to manage the deep ripping in a local context requires demonstration in the local environment as well as ameliorating multiple constraints such as non-wetting. Growers require confidence in adopting these amelioration methods locally.

The current ripper gauge investment has provided significant information to growers in some regions as it was applied on several different locations. The region proposed by this new investment, traditionally, has been under serviced and there is significant scope to extend current knowledge to these growers. This small investment could have a significant impact on the profitability of these growers and provide them with new knowledge on the management of their soil types. This work is required in the identified locations as well as the consideration of the interactions of multiple constraints. Interest from growers in the Esperance port zone is high regarding strategic tillage with a combined approach to management of multiple constraints which will make amelioration much more profitable.

This investment proposes to add three new locations to be located on major soil types within the western areas of the Esperance port zone, that will view two separate timings of ripping side by side within a farming system package to maximise profitability. It is proposed to conduct work at these site for two years to demonstrate the longevity of the benefits to growers.