ANSWERING the questions of when to make the big moves in farming is now a lot easier for Western Australian farmers thanks to the Yield Prophet system.
As a member of the Northern Agri Group, West Ogilvie grain grower Karl Suckling has been using the software to make more accurate decisions about marketing, as well as the timing and volumes of his fertiliser applications.
At any point in the season Yield Prophet can predict likely yields by combining rainfall forecasts, soil types, and crop varietal information, with data from growers such as fertiliser inputs and irrigation applications.
“The project has been a massive success for our members,” Mr Suckling said. “The big benefits that I get out of the Yield Prophet project are once the seeding dates are in the system for each paddock, it projects forward certain important timings – for example for fungicide applications at flag leaf emergence, it will model out a date that is usually within two or three days of what it tells you.
“It also gives us really important data on nitrogen applications and whether or not we’re at the level we need to be at different points in the season, given the amount of rainfall we’ve had and whether we need more nitrogen to make the most out of the situation.”
The Northern Agri Group is now in its third year using the Yield Prophet software, which was developed by the Birchip Cropping Group (BCG) and the CSIRO, and is available from BCG to producers on a subscriber basis.
The Grains Research and Development Corporation (GRDC) has been assisting grower networks in adopting the Yield Prophet system as a means to bolstering productivity through more efficient use of fertiliser.
The Northern Agri Group initially implemented the program with the assistance of the Department of Agriculture and Food WA (DAFWA), while support from the GRDC has allowed the group to increase the number of soil samples taken in the region and expand its relevance to local growers.
“Within the Northern Agri Group there’s a massive variation in high to low rainfall and soil types, so we have strategically chosen eight sites for soil sampling – two of them east, two west, two north and two south – and that covers off our high, medium and low rainfall areas and each soil type specifically within each area,” Mr Suckling said.
“We soil core at the start of the year to determine available soil moisture and nitrogen at the time of sowing; after that we input rainfall data as the season goes along and Yield Prophet calculates where our yield should be at and what additional nitrogen applications we should apply if we are to optimise yield in that season.”
Mr Suckling farms almost 6000 hectares, made up of about 2000 ha of sandy soils and 4000 ha of red loams and clays. The area only receives 350-400 mm of rain each year, most in winter, while the warmer daytime temperatures shorten the growing window for winter crops.
Canola, lupins and wheat are grown in rotation, with approximately 1500 ha sown to canola, 900 ha to lupins and 3600 ha to wheat each season.
The family starts seeding for canola between April 15 and 20 of April, regardless of soil moisture levels, with wheat sowing beginning between April 25 and May 1, and lupins following immediately after. Crops are fertilised heavily at sowing, with Agras Extra used on the heavier soils and MacroPro Extra added to the sand plain country.
About four weeks after crop emergence, between 50 and 80 litres/ha of Flexi-N liquid fertiliser is applied to the crops on the red soil country, and a blend of potash, sulphate of ammonia and urea is top dressed on to the sandy soils.
“We put a lot of fertiliser on up front to give us more time to make our fertiliser and marketing decisions later in the season,” he said. “We can wait as late as mid tillering before making a decision on whether or not to put more fertiliser on.”
Mr Suckling said fertiliser rates at sowing had not changed as a result of adopting Yield Prophet – rather the decision making tool was allowing him to make more confident and precise decision about if, when and how much fertiliser to apply later in the season.
“If there’s a price spike, or if we receive good in-crop rainfall, we will use Yield Prophet to get a second opinion on how hard we should go in pursuit of top yields,” he said.
This season Yield Prophet is forecasting an 80 per cent chance of yielding 1.8t/ha and a 60 per cent chance of 2.5t/ha, with both potential outcomes not warranting the expenditure on additional fertiliser.
“As the season goes on, it helps us fine tune our fertiliser rates as well as our marketing options,” Mr Suckling said. “Despite the high prices at the moment, we have chosen not to forward sell more grain because the production risks are still too high.
“If it stays dry this season, we probably won’t need to use Yield Prophet again, but if we receive enough rain in August or September we might have a chance of achieving 3t/ha and then we will revisit Yield Prophet to determine how hard we should go in chasing this result.”
This is in stark contrast to 2011 when an abundance of soil moisture and ideal growing conditions had Yield Prophet forecasting an 80 per cent chance of more than 4t/ha.
“We had a lot of moisture in reserve and the probabilities provided by Yield Prophet gave us the confidence to market our crop more aggressively,” Mr Suckling said.
“It told us to load up with nitrogen, so we went hard and averaged 4t/ha with some paddocks going over 5t/ha, which we’ve never done before.”
Based on the Yield Prophet forecast the Sucklings applied an additional 50 units of nitrogen per hectare at a cost of $25-$30/ha, but delivering a return of between $200-$300/ha.
“That was a big commitment of money at a point in the season when cashflow was short, but we were confident it would pay dividends and it did.”