‘Reefinator’ machine aids southern Wheatbelt family in quest to achieve sustainable cropping system

A farming family from WA’s southern Wheatbelt are using multiple crop competition tactics such as deep ripping machinery and soil amelioration to establish a sustainable cropping system on their 8800 hectare property. Kim and Michelle Slarke of Lake Grace, as part of their journey for achieving better soil health, have used the Reefinator, a rock-crushing, deep-ripping machine that is used to increase soil depth and create an optimal seed bed in ironstone gravel zones, where crops generally struggle to establish. The Reefinator, a machine invented by WA farmer Tim Pannell, has helped the Slarke family by mixing in previously applied nutrients and lime to support competitive crops in previously low-yielding areas prone to weeds. According to the Slarkes, the Reefinator requires up to five passes over a few years to create 160 to 200 mm of soil depth. To collect surface rocks from their paddocks, the Slarkes use a rock picker, which clears away both rocks and sticks and allows for a safe harvest at night. The Slarke family also uses variable rate technology to apply soil amendments to fertiliser, a method that started in 2010 when they purchased an air-seeder with VRT capabilities. Other strategies have been implemented to encourage crop competition, including high seeding rates, east-west sowing, narrower row spacing and variable rate nutrients and soil amelioration. “Soil health is the number one driver for our business,” Mr Slarke said. “We have done our best to respect our soils and improve soil health so our crops can reach their yield potential for the rainfall received. Nearly 30 years ago, we started addressing the low pH of our soils with lime applications.” Mr Slarke said the liming programs has shown clear benefits, with the use of gypsum also proving to be a success as it reduces the hard-setting traits of heavier clays. The Slarke family implemented east-west sowing across their farm 15 years ago, when they started auto-steer farming. Mr Slarke said they took on the east-west sowing approach because of research conducted by groups such as the Grains Research and Development Corporation, which found east-west planning, particularly in cereals, was beneficial for competition against weeds. “About 95 per cent of the cropped area is sown east-west or close to it, depending on the shape of the paddock and finding a practical AB line for machinery operations,” he said. “It was fairly easy to maintain east-west sowing when we removed the fences and established the block farming layout.”