Jordan White (right) discusses canola’s need for early sulphur as identified in Fuel Gauge strips with Summit Area Manager Juliet McDonald (left). This crop of 44Y27 canola yielded close to 2t/ha on just 150mm of growing season rainfall.
As seasons come and go there is always more to learn with crop nutrition as Tim Broun would happily agree. Tim and wife Daneill farm north-east of Coorow. They have a typical central wheatbelt mix of soils on their lime responsive Wodjil country.
Sometimes, the signs of underlying nutrient deficiency are not always obvious. It can require testing different things to unravel what is really going on beneath the soil surface.
In 2019, Summit Area Manager Juliet McDonald placed three nutrient rich Fuel Gauge strips in one of Tim’s canola paddocks.
The first strip was enriched with nitrogen, the second, nitrogen plus potassium and the third strip had high levels of nitrogen, potassium and sulphur.
According to Jordan White, the impact of the Fuel Gauges was impressive. Jordan has worked for Tim and Daniell since 2017 and recalled 2018 turned out to be a record year for many farmers in their area.
“Crops in 2018 ended up with heavy crops and massive stubble loads after harvest. Our paddocks had a lot of nutrients locked up in the stubble,” Jordan said.
“The 2018 harvest was followed by virtually no summer rain to breakdown the stubble and a late break to the 2019 season.
“We basically dry seeded almost everything last year and about 100mm of rain fell in the month after.
“On the deep ripped Wodjil country in particular, the more mobile nutrients just got leached down below the establishing crop’s root zone at a critical time and it struggled to establish.
Canola seedlings in particular were small, lethargic plants which even a month after emergence were tiny. Some were turning red and looked like they were about to die. We’d almost written it off.
That’s when Juliet’s Fuel Gauge strips really came into their own. We had assumed it was nitrogen deficiency and the plan at the time was to give it shot in the arm with liquid UAN. We were literally a day or two from pulling the trigger with UAN when we saw the fuel strips.
“The nitrogen strip, which had a luxury level in excess of 100 units of N showed almost no response.
“We could see a bit of a response in the nitrogen plus potassium strip, but canola seedlings in the nitrogen, potassium and sulphur strip were well established plants, already starting to cabbage up nicely and using all the rainfall we had there.
“That’s when we realised it was sulphur that was holding the canola back the most. It was either tied up in the previous year’s stubble, or had washed out of the seedling root zone, or both. They would get it eventually,but that was going to be too late for us.
“The UAN (containing 32% nitrogen) changed to a dose of liquid MAXamFLO (containing 22% nitrogen and 6.2% sulphur) which brought it back from the brink and we ended up with a break-even canola crop in what was rainfall wise a terrible year. The farm had the early 100mm and then not a lot more for the rest of the growing season, so that was our one shot to get it up and growing.
“In 2019 we bought enough MAXamFLO to do two applications to the canola a few weeks apart. In the middle of July, we gave it the first hit and then a month later with no more rainfall and no more on the horizon we pulled out of the second application.
“That meant we had MAXamFLO liquid left over from last year that we put down with the canola this year and it gave us phenomenal canola establishment.
“We saw season breaking rain coming in in late May and three to four days out we hooked into it. All the canola got 100L/ha of MAXamFLO underneath at sowing.
“Usually, we’d variable rate but 100L of MAXamFLO was less nitrogen than would be the normal rate of UAN. That was the maximum capacity of the air seeder so that’s what we went with.
“We reckon we’ve had the best canola establishment and early vigour that we’ve ever had this year".
“It’s pleasing because up here the job is to get as much growth into our crops before that late July period. We try to stack on the yield early so getting it up and out of the ground is absolutely crucial.”
Jordan said their canola yields this year averaged close to 1.8t/ha after a dry, late start and growing season rainfall of just below 150mm.