Sowing Reports. Angela Mazur, Liebe Group Clare Johnston, Liebe Group Laurence Carslake, Farmanco. The sites being modelled in 2012 are:

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1 Yield Prophet 2012 V O L U M E 3 R E P O R T 1 M A Y The Liebe Group would like to thank their Diamond sponsors for their ongoing support Sowing Reports Angela Mazur, Liebe Group Clare Johnston, Liebe Group Laurence Carslake, Farmanco INTRODUCTION Welcome to the first Yield Prophet report of Yield Prophet is a web based interface for the agricultural production simulation model (APSIM). It uses real-time information from the paddock to simulate how the crop is growing. By using historical rainfall records it can determine probabilities of how a crop may yield. This provides a forecast of the chance of achieving a certain yield at any point in time during the season. From this we can match inputs to these yield potentials. The accuracy of the forecasts depends highly on the soil type characterisation. Many of the sites used in this report have been properly characterised, however, there are a couple of sites where the soil type is only an estimate and therefore may not be accurate. The model does have limitations (it can t model weeds and diseases) and the information presented is designed to only be used as a guide to help understand soil water and Nitrogen dynamics. The model is based on a well managed crop and therefore is a useful indicator of yield potential given soil water and inputs. The sites being modelled in 2012 are: Yellow deep sand, Mike Dodd - West Buntine. Red clay, Harry Hyde - Dalwallinu Red deep loamy duplex, Keith Carter - East Wubin (Partially characterised) Acid sandy earth, Keith Carter - East Wubin (Partially characterised) Red deep loamy duplex, Doug Cail - Goodlands Those sites partially characterised are based on nearest match. A characterised site in Wongan Hills was going to be used in the Yield Prophet model this year, however, the site is going into Lupins which cannot be modelled by APSIM Look out for it in 2013.

2 RESULTS FROM LAST YEAR In 2011, the results predicted by the model were similar to those actually harvested, particularly the case for the acid sandy earth at East Wubin, with the Yield Prophet predicted yield and actual yield both at 2.9 t/ha. Table 1. Yield Prophet yield predicted on 18 October 2011, compared to final yields and quality. Site Yield Prophet predicted yield (18/10) t/ha Actual Yield (t/ha) Birch Main Trial Site Long Term Research Site Acid sandy earth, East Wubin Red deep loamy duplex, East Wubin SOIL CHARACTERISATION The characterisation process involves the measurement of the parameters indicated on the next page (Stored Soil Water), so that a reasonably accurate indication of plant available water can be gained. This process is mostly very accurate however does have some quirks that may be cause of some variability within the model. For example, as explained above, the Crop Lower Limit is the amount of water available after the crop has extracted all the water it possibly can. However, if this measurement was taken in a dry year, then plant root growth may have been limited to a shallow depth. This means that in some cases, the CLL measured at depth may be over estimated, because there was no root growth there to extract the plant available moisture. The Goodlands site is an example of this as it was characterised in the very poor year of The crop lower limit at depth may also be overestimated by any other constraints that can restrict root growth, such as extremes in ph, deep hard pans or deep structural problems. THIS REPORT CONTAINS: SOWING OPPORTUNITY GRAPHS This report puts different varieties up against historical local climate data to determine potential yield based on sowing date. Crop growth and yields are simulated from soil type and soil moisture information. The risk of frost and heat shock are presented by variety or more precisely, maturity time. The model works on maturity rather than physiological differences in varieties, therefore the graph is a risk percentage of the heat or frost condition occurring during flowering. (When Calingiri and Magenta are modeled they look the same). Frost and heat shock do not feed into yield predictions, they are presented to let you determine how a variety will be influenced with different times of sowing. Soil type has no influence on these graphs. SOIL NITROGEN GRAPHS Soil Nitrogen graphs are graphed throughout the report. These measurements are taken pre-seeding by Liebe staff members using standard CSBP soil test results. As the season progresses, the model estimates the crop nitrogen usage and the impact of mineralization processes. As the crops grow and roots deepen, you will see a draw down of soil N reserves at different depths. Where bulges occur at depth, as indicated on the graphs, this may indicate that the roots cannot access this zone due to ph or other constraints that were identified in the characterization process. These graphs also indicate a final rooting depth which is determined by the farmers knowledge of the paddock or identified constraints. Yield Prophet Report - May 2012 Working Together in Agriculture 2

3 SITE 1 DESCRIPTION Farmer: Mike Dodd Location: Buntine Marchagee Rd, West Buntine Soil Characterisation: Yellow deep sand Accumulated Rainfall 2012: 73mm Plant Available Water Capacity (size of bucket): 136mm Current water available: 44mm STORED SOIL WATER GRAPHS The following graphs show the current soil water levels from the differing soil types throughout the Liebe area. Each of these contains the following information : Plant Available Water (PAW) Amount of water that is potentially available to the plant (shaded area). Soil Plant Available Water (Soil PAW) same as PAW. Current Crop Plant Available Water (PAW) - the soil water currently accessible to the roots determined by the current rooting depth. Crop Lower Limit (CLL) - the amount of water remaining after a particular crop has extracted all the water available to it from the soil. Drained Upper Limit (DUL) Amount of water the soil is able to hold after drainage has finished. Plant Available Water Capacity (PAWC) The difference between the upper water storage limit of the soil (DUL) and the lower extraction limit of the crop, also know as the size of the bucket. SITE 1 The yellow deep sand in figure 9, is an even soil type to depth, with little constraints, it has large pores, allowing an even distribution of water to move straight down the soil profile. This site has mild acidity at depths 10-20cm with a ph of 4.4 and 20-40cm with a ph of 4.7. Current Nitrogen Status: 92 kg/ha 0-210cm Figure 9. Distribution of plant available water on a yellow deep sand at West Buntine. This sandy site has less N than the other sites, with 92 kg/ha, this amount is cumulative total N located through the soil profile up to 210cm. Figure 11. Distribution of sol nitrogen on a yellow deep sand at West Buntine on 15th of May Yield Prophet Report - May 2012 Working Together in Agriculture 3

4 SITE 2 DESCRIPTION Farmer: Harry Hyde Location: Dalwallinu West Rd, Dalwallinu Soil Characterisation: Red clay Accumulated Rainfall 2012: 73mm Plant Available Water Capacity (size of bucket): 164mm Current water available: 38mm Current Nitrogen Status: 327 kg/ha 0-170cm SITE 2 Figure 1. Sowing opportunity for Mace, modelled on a red clay, Dalwallinu. The model in figure 1 is predicting that the optimum sowing time for a variety like Mace is from the 1st to the 15th of May at Dalwallinu assuming rainfall and seasonal conditions are in line with the long term average. Figure 2 is showing that the optimum sowing time for a longer season variety like Calingiri declines after an early sowing opportunity at Dalwallinu. The model is looking at crop maturity and season length on this soil type. In reality if the season ends with a very good finish then a long season variety will yield above the predicted yield and well below the predicted yield if the season finishes early. Figure 2. Sowing opportunities for Calingiri, modelled on a red clay, Dalwallinu. The soil in Figure 7 is a red clay at Dalwallinu. This paddock was fallowed last year and has a calcareous layer and subsequent alkalinity at depth, which could be causing restricted root growth. This soil is commonly known as Crabhole Country. We suspect the roots can only grow to 90cm (black line in graph) because of the calcareous layer. This is limiting yield and a further 50mm of water and potentially 1 t/ha extra grain yield could be available because the soil can hold more water than the plant can access. This paddock has a high level of variation, in particular due to the calcareous deposits throughout the paddock. These deposits occur at different depths, lead to high ph and potentially structural issues. There is not much the farmer can do about these. Figure 7. Stored soil moisture on a red clay at Dalwallinu. Yield Prophet Report - May 2012 Working Together in Agriculture 4

5 The red clay in Dalwallinu was fallowed in 2011 and has a cumulative total of 327 kg/ha of N up to 160cm (Figure 15). This is amount is significant and can potentially be explained through N fertiliser carry over from previous seasons and given the soil has held a high amount of moisture in the fallow, increased soil microbial activity causing mineralisation of organic N. This amount of nitrogen held in this soil type increases the risk of a crop haying off later in the season if faced with a tight finished as it may set up a high biomass crop, which may run out of moisture late given the high Crop Lower Limit of the soil type. Figure 15. Current distribution of nitrogen on a red clay at Dalwallinu on 11th of May Yield Prophet Report - May 2012 Working Together in Agriculture 5

6 SITE 3 DESCRIPTION Farmer: Keith Carter SITE 3 The soil in figure 5, a deep loamy duplex east of Wubin, can hold 120mm in the top 1.8 meters as of the 9th of May, this is 43% full. This soil has mild acidity in the first 10cm with a ph of 4.9. Location: Rabbit Proof Fence Rd, East Wubin Soil Characterisation: Red deep loamy duplex Accumulated Rainfall 2012: 45mm Plant Available Water Capacity (size of bucket): 120mm Current water available: 52mm Figure 5. Stored Soil Moisture on an red deep loamy duplex at East Wubin, 9th of May Figure 6 shows the stored soil moisture of the same soil in This model shows there is less water available in the soil at this time last year when the soil was only 3% full. Current Nitrogen Status: 125 kg/ha 0-170cm Figure 6. Stored Soil Moisture on an red deep loamy duplex at East Wubin, 15th of May This soil contains more N than most of the other soils samples, with 125 kg/ha available up to 160cm. The majority of this 125 kg/ha of N is between cm. Figure 14. Current distribution of nitrogen on a red deep loamy duplex at East Wubin on 9th of May Yield Prophet Report - May 2012 Working Together in Agriculture 6

7 SITE 4 DESCRIPTION Farmer: Keith Carter SITE 4 The sandy earth in figure 10 is east of Wubin. It is a soil with 17mm of water currently available in a soil that is able to hold 142mm of water. The ph is typical of an acid soil with the ph being as low as 4.3 at 20-40cm. Location: Wubin East Rd, East Wubin Soil Characterisation: Acid sandy earth Accumulated Rainfall 2012: 22mm Plant Available Water Capacity (size of bucket): 142mm Current water available: 17mm Current Nitrogen Status: 76 kg/ha 0-210cm Figure 10. Distribution of plant available water on a acid sandy earth at East Wubin. Figure 12 highlights more nitrogen between 50cm and 100cm deep. This may indicate that there is an acid layer that is preventing or limiting root access to the available nitrogen. This sandy earth has less N than the other soils samples, however it still contains 76 kg/ha of N up to 210cm. Figure 12. Distribution of soil nitrogen on a acid sandy earth at East Wubin on 9th of May Yield Prophet Report - May 2012 Working Together in Agriculture 7

8 SITE 5 DESCRIPTION Farmer: Doug Cail Location: Glamoff Rd, Goodlands SITE 5 Figure 8 is a Goodlands Soil. This soil type has 49mm of water available. As mentioned earlier the CLL of this soil may be slightly over estimated, given the characterisation was done in a poor year. Thus the bucket may be slightly larger than the 120mm reported here. Soil Characterisation: Red deep loamy duplex Accumulated Rainfall 2012: 71mm Plant Available Water Capacity (size of bucket): 120mm Current water available: 49mm Current Nitrogen Status: 215 kg/ha 0-160cm Figure 8. Stored soil moisture on a red deep loamy duplex at Goodlands, 9th of May The duplex soil types also have good N levels, with 215 kg/ha in Goodlands (figure 13). It has 58 kg/ha of N available in the top 10cm alone. This abundance of N in the top layer is potentially due to high mineralisation, N from residual in previous years and low leeching. Figure 13. Current distribution of soil nitrogen on a red deep loamy duplex at Goodlands on 9th of May Yield Prophet Report - May 2012 Working Together in Agriculture 8

9 SOWING X VARIETY COMPARISON SCENARIO S This is where the model starts predicting crop growth and yield based on different germination dates. Please note that the model compares maturities rather than varieties. In these reports you can change crop type, variety and seeding date. When interpreting results it is important to consider the starting sub soil moisture and nitrogen levels, which will have an effect on the predicted yields. Figure 3 shows potential yields and varieties with different maturity times germinating on 9/5/2012 in an average (50%) season. Mace has the highest yield potential of 3.3 t/ha, then Zippy at 3.2 t/ha, and Calingiri at 2.9 t/ha, given a 9th of May germination. Figure 3. Yield outcomes of Calingiri, Mace & Zippy sown on the 9th of May on a yellow deep sand at West Buntine. Figure 4 shows potential yield for Calingiri at different germination times. It shows a variation in yields, decreasing as the germination date gets later. In an average year, Calingiri germinating on the 9th of May yields 2.8 t/ha, 30th May yields 2.2 t/ha, and 20th of June yields 1.8 t/ha. Figure 4. Yield outcomes for Calingiri sown on 3 different dates on a yellow deep sand, West Buntine. Key Message: The shorter season varieties like Mace and Zippy will most likely out yield the longer season varieties given a May germination time. Yield data from NVT trials would indicate that Mace will out yield Zippy on most occasions. Estimated yields used are for the 50% probability outcome. Yield Prophet Report - May 2012 Working Together in Agriculture 9

10 Figures 16 & 17 show the plant available soil moisture state wide. The availability of moisture in the soil is higher for most part of the area this year compared to Results from 2011 showed that there was less water in the soil than there is currently. Figure 16. Plant available soil moisture for 1st May Figure 17. Plant available soil moisture for 2nd May Source: Yield Prophet Report - May 2012 Working Together in Agriculture 10

11 CONCLUSION The predicted yields in some of these reports are similar to those run in 2011, in particular some of the sowing x variety reports were run similar to those last year. The model highlights some of the limitations on different soil types throughout the region. The soil type classification gives you a guide to plant available water and the plants rooting depth. There will be variation within many paddocks as soil type and subsoil constraints change. There are some major variations to stored soil nitrogen by soil type and rotation. Of particular note the fallow land on red clay at Dalwallinu has very high levels of nitrogen stored. ACKNOWLEDGEMENTS Grains Research and Development Corporation. Department of Agriculture & Food, WA Yvette Oliver, CSIRO Disclaimer: Yield Prophet information is used entirely at your own risk. You accept all risks and responsibility for losses, damages, costs and other consequences of using Yield Prophet information and reports. To the maximum extent permitted by law, Agricultural Production Systems Research Unit and Birchip Cropping Group excludes all responsibility and liability to any person arising directly or indirectly from using the information generated by Yield Prophet. Yield Prophet Report - May 2012 Working Together in Agriculture 11