In spite of the ongoing dry conditions on both sides of the continent, a forecasting tool developed by CSIRO is predicting wheat yields across the country will be above the long-term median. Using its Wheatcast tool CSIRO has national wheat yields at an average of 1.88 tonnes a hectare, 3 per cent above the 15 year national average of 1.82t/ha. The Wheatcast tool uses a range of data, including rainfall and stored moisture levels, along with modelling programs such as the Agricultural Production Systems Simulator, (APSIM) to come up with numbers that are updated fortnightly. As of October 1, the last Wheatcast run, there was a healthy 65pc chance of exceeding the long-term median yield with median plant available water of 53mm likely to be of critical importance to allow crops to finish. Crops in Victoria, NSW and South Australia are likely to exceed long-term means, while in WA and Queensland it is expected they will not. Interestingly there is a strong likelihood NSW crops will exceed the median, with current yield estimates at 2.12t/ha compared to the long term median of 1.93t/ha. CSIRO has a 72pc likelihood of exceeding the long-term mean. Given the state of crops in the state's north, which have been hit hard by the dry conditions it is a vote of confidence in the yield potential through the Riverina region, which received yield bolstering rain last week. Victoria is the best off state in terms of the likelihood of exceeding long term means, at 76pc. It also has the highest yield outlook at 2.29t/ha, compared to the median of 2.01t/ha. In Queensland, which has the lowest yield potential in the country at 1.33t/ha, there is no chance of reaching the median of 1.49t/ha with headers already rolling in the state's more northern cropping zones. South Australia is the most delicately poised state, with current yield potential of 1.87t/ha compared to the long term average of 1.78t/ha, with a 59pc chance of exceeding the median. The dry condition in Western Australia's northern cropping belt in particular have put that state behind the eightball in its bid to exceed median yields. CSIRO has this year's yields pegged at 1.58t/ha compared to 1.73t/ha historically, with just a 13pc chance of getting above median yields. Victoria has the most plant available water in reserve, with 76mm, compared to just 25mm in Queensland. However, there is the most uncertainty regarding yields in Victoria, with yield forecast uncertainty of over 1t/ha in some parts of the state. In other, more advanced regions, there is more clarity as to the potential of the crops.
