A heavy-duty subsoil amelioration machine is helping to overcome the yield barrier posed by hostile, deep soils in south-west Victoria. The machine was purpose-built for subsoil manuring at Yaloak Estate a 5500-hectare operation spread across seven Victorian properties at Fiskville, Meredith, Kyneton, Ballan, Cobden, Mortlake and Hamilton.
Yaloak Estate farm manager Rob Binks says the prototype originated from trials hosted by the businesss Fiskville property, 85 kilometres north-west of Melbourne, in 2005. The research was co-funded by the Australian Research Council and Yaloak Estate. Rob says these trials showing the yield limitation that stems from dispersive, sodosol subsoils provided the initial stimulus for Yaloak Estate, owned by Ballan Pastoral Company, to invest in the machines development. These La Trobe University trials showed pelletised Dynamic Lifter® fertiliser and lucerne, applied separately at 20 tonnes per hectare in the 30 to 40-centimetre deep soil layer, increased wheat yields by 60 per cent.
Keen to secure this yield-lift, largely as a consequence of improved soil structure, the Yaloak Estate team began to develop a six-metre machine on-farm at Fiskville in 2010. Its novel design, purpose-built for applying chicken litter at 20t/ha, was refined over a five-year period.
Iterations in the prototypes development, however, with emphasis on operational efficiency and capacity to apply heavier soil amendments, eventually saw the 6m machine upgraded to an 8m machine.
Built by Dunstan Farmers Engineering in 2015, the new 8m machine uses a high-pressure airstream to deliver soil amendments from a trailer through a series of distribution hoses to single, deep-ripping tynes fixed to an 8m bar.
Rob says its robust construction was needed to handle the latest Yaloak Estate formula for subsoil amelioration. This dense, heavy mix contains chicken litter, green compost waste, gypsum and biosolids (treated sewage sludge).
The business has added a new range of ameliorants to its subsoil-manuring program because the price of chicken litter has nearly doubled in the past 10 years, Rob says.
In 2019 and 2020, Yaloak Estate is hosting new trials looking at subsoil manuring with thermally dried, pelletised biosolids (T1C2 grade) as part of GRDCs $4 million Innovation Program.
Federation University Australia research fellow Dr Nimesha Fernando established the Victorian trials at the Ballan Yaloak Estate property in the high-rainfall zone, and at Chris Sharkeys property at Balliang in the intermediate-rainfall zone this year.