Page 1 Page 2 Page 3 Page 4 Page 5 Page 6 Page 7 Page 8 Page 9 Page 10 Page 11 Page 12 Page 13 Page 14 Page 15 Page 16 Page 17 Page 18 Page 19 Page 20 Page 21 Page 22 Page 23 Page 24 Page 25 Page 26 Page 27 Page 28 Page 29 Page 30 Page 31 Page 32 Page 33 Page 34 Page 35 Page 36 Page 37 Page 38 Page 39 Page 40 Page 41 Page 4233 IREC Farmers' Newsletter No. 196 — Summer 2016 The project had two core sites, one at Boort in northern Victoria and the other at Leeton Field Station in southern New South Wales. The Victorian site focused on the technical aspects of double cropping, including herbicide options and stubble management, and the NSW site focused on different cropping sequences to quantify achievable crop yield and profitability. This article reports on the Leeton experiment. The experiment The trial site was established at Leeton Field Station in a field with a history of irrigated lucerne. The paddock was formed into 1.83 metres wide beds suitable for furrow irrigated cropping. The crop sequencing started in early 2014 with a winter cropping or fallow phase. The project ran for two years (four cropping seasons) ending in mid-2016 with the harvest of the second summer cropping phase. The trial included both single cropping (one crop per year) and double cropping (two or three crops in two years) treatments. The experiment had seven treatments with four replications of each treatment (Table 1). Each plot was three beds wide by 120 m long, giving a total plot area of 660 m2 and a treatment area of 0.264 ha. There was a fallow buffer area of one bed between each plot. Table 2 shows the commodity prices (ex GST) used in the gross margin analysis. Most prices were sourced from the Igrain website for the 2014–15 season. Commercial prices were sourced from retailers or contractors for the cost of chemicals, fertilisers and contract harvesting. Some cotton costs were sourced from the NSW DPI 2014– 15 cotton gross margin budgets for southern NSW. Commodity prices and variable input costs were kept consistent over both years to ensure the final results were not impacted by using inconsistent sources of input data across seasons. Treatment description and results Treatment one (T1) The 2014 winter phase was left as fallow. The 2014–15 summer phase was sown with Djakal soybeans 20 November 2014, irrigated with 8 ML of water and harvested 5 May 2015 with a yield of 3.09 t/ha. The 2015 winter phase was left as fallow. The 2015–16 summer phase was sown with P1756 maize 7 October 2015, irrigated with 10 ML of water and harvested 22 March 2016 with a yield of 13.4 t/ha. Treatment two (T2) The 2014 winter phase was left as fallow. The 2014–15 summer phase was sown with Djakal soybeans 20 November 2014, irrigated with 8 ML of water and harvested 5 May 2015 with a yield of 3.36 t/ha. The 2015 winter phase was left as fallow. The 2015–16 summer phase was sown with Djakal soybeans 26 November 2015, irrigated with 7 ML of water and harvested 6 April 2016 with a yield of 3.09 t/ha. Table 1. Summary of the seven treatments evaluated in the crop sequencing experiment at Leeton Field Station Table 2. Summary of commodity prices used Season/year Treatment T1 T2 T3 T4 T5 T6 T7 Winter 2014 Fallow Fallow Fallow Wheat Wheat Barley Canola Summer 2014–15 Soybean Soybean Cotton Soybean Fallow Soybean Maize Winter 2015 Fallow Fallow Faba bean Wheat Wheat Barley Faba bean Summer 2015–16 Maize Soybean Fallow Soybean Fallow Soybean Fallow Commodity Price Wheat – APW $258 per tonne Barley $241 per tonne Canola – no grade $449 per tonne Soybean – no grade $512 per tonne Maize – feed $287 per tonne Cotton lint $500 per bale Cotton seed $300 per tonne Faba beans $450 per tonne The crop sequencing project at Leeton Field Station, August 2015. Irrigation of cotton, with wheat fallow (left) and maize (right).