Low Rainfall Zone (LRZ): The low-rainfall zone of South Australia, Victoria and NSW
This region is characterised by an average annual rainfall of 250–350 mm, of which ~70% falls during the April–October cereal growing season, with highly variable soils often in a dune–swale complex. The dryland farming system is typically based on wheat, barley and annual pasture, with relatively small areas of canola and pulse legume crops such as peas and lupins. Farm businesses with both cropping and livestock remain common in the Mallee.
The area of perennials in the Mallee region is currently low. It is likely that new options with improved suitability for the cropping-oriented low-rainfall farming system where annual average rainfall is <350 mm will need to emerge if perennial legume adoption is to increase in the Mallee.
The areas of research activity in the LRZ are broadly based around subtropical grasses and forage shrubs. The potential for tropical grasses to fill a small niche on marginal soils aimed at providing summer–autumn feed was identified as being tested. The most commonly grown perennial forage shrub is old man saltbush (Atriplex nummularia Lindl.). It has a demonstrated ability to grow on soils marginal for cropping and provide summer–autumn feed as well as shelter for livestock. There is potential for greater use of forage shrubs on soils marginal for cropping, but improved plant options or species mixtures are likely to be needed, in particular options offering improved feed quality, together with a clearer demonstration of the economic value, if substantial increases in perennial forage shrub plantings are to occur.
Interest in alternative uses for marginal cropping soils is also increasing, with grazing of cereals on soils with subsoil constraints being one example.
Descheemaeker, K, Llewellyn, R, Moore, A, Whitbread, A (2014a) Summer-growing perennial grasses are a potential new feed source in the low rainfall environment of southern Australia. Crop & Pasture Science 65, 1033–1043. http://www.publish.csiro.au/?act=view_file&file_id=CP13444.pdf
Descheemaeker, K, Smith, AP, Robertson, M, Whitbread, A, Huth, N, Davoren, W, Emms, J (2014b) Simulation of water-limited growth of the forage shrub saltbush (Atriplex nummularia Lindl.) in a low rainfall environment of southern Australia. Crop & Pasture Science 65, 1068-1083. http://www.publish.csiro.au/?act=view_file&file_id=CP13452.pdf
Gupta, V, Kroker, S, Davoren, B, McBeath, T, McKay, A, Ophel-Keller, K, Llewellyn, R, Roget, D (2013) Summer weed control benefits Rhizoctonia disease management in cereal crops. In ‘Research Compendium 2012.’ pp. 5. (Mallee Sustainable Farming) http://msfp.org.au/wp-content/uploads/2013/06/2012-Summer-weed-control-benefits-Rhizoctonia-disease-management-in-cereal-crops-Root-Disease.pdf
Gupta, V, Llewellyn, R, McBeath, T, Kroker, S, Davoren, D, McKay, A, Ophel-Keller, K, Whitbread, A (2012) Soil biology and Rhizoctonia disease management update – Break crop experiments at Karoonda. In ‘Mallee Sustainable Farming Results Compendium 2011.’ (Mallee Sustinable Farming Inc: Mildura) http://msfp.org.au/wp-content/uploads/2013/10/Soil-biology-and-Rhizoctonia-disease-managment-update-Break-crop-experiments-at-Karoonda.pdf
Gupta, V, Roget, D, Davoren, C, Llewellyn, R, Whitbread, A M Unkovich (Ed.) (2008) ‘Farming system impacts on microbial activity and soil organic matter dynamics in southern Australian Mallee soils, Global Issues Paddock Action, Proceedings of th 14th Australian Agronomy Conference.’ Adelaide. (Australian Society of Agronomy. Available at http://www.regional.org.au/au/asa/2008/concurrent/crop-agronomy/5918_guptavvsr.htm
Llewellyn, R, Robertson, MJ, Hayes, R, Ferris, D, Revell, C, Descheemaeker, K (2013) A strategic approach to developing the role of perennials for crop-livestock farmers. In ‘Revitalising Grasslands to Sustain our Communities: Proceedings 22nd International Grassland Congress. Sydney, Australia’, 15-19 September 2013. (Eds DL Michalk, GD Millar, WB Badgery, KM Broadfoot) http://edepot.wur.nl/306309
Norman, HC, Masters, DG, Wilmot, MG, Rintoul, AJ (2008) Effect of supplementation with grain, hay or straw on the performance of weaner Merino sheep grazing old man ( Atriplex nummularia) or river (Atriplex amnicola) saltbush. Grass and Forage Science 63, 179-192. http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2494.2007.00623.x/abstract