Banding nitrogen (N) at seeding is critical for setting your crops up to reach their full potential. Fewer legume rotations, longer rotations, lower soil N reserves and high residue levels are all contributing to higher N requirements, especially now that we are seeing greater yield potential from improved farming practices and soil improvement as well as varietal gains. What we are seeing in the field is the lack of higher protein wheat that is being produced and the opportunity that presents itself with favourable $/t spreads to APW and AH.
2018 gave us the opportunity to showcase that Flexi-N banded at seeding is the premium product to use whilst also giving us the chance to utilise a mid-row banding machine for in season N applications to explore further efficiency gains from applied N.
Trial - Kinliavan - Scaddan W.A.
Fig 1. - Scaddan rainfall mm - November 2017-October 2018
Fig 2 - Soil test results- Kinliavan 2018
• No establishment issues-
Banding N at seeding can be seen as risky especially in dry starts. The ability of Flexi-N to be placed in the right location under the seed with reduced risk of toxicity effects makes it ideal for this task compared to a granule such as urea. 100L/ha of Flexi-N (42 units N/ha) was chosen as our banding rate and although we had good sub soil moisture from good summer rain we seeded on the 1st May into a dry seedbed. A 9mm event in mid to late May was enough for the crop to germinate and we had no visible difference in plant density between 100L/ha Flexi-N banded compared to nil.
Fig 3.- Banding 100L/ha of Flexi-N didn’t affect crop establishment.
100L/ha of Flexi-N vs Nil
• Maintaining potential
Banding Flexi-N at seeding meant that we were able to maintain our yield potential even though the season wasn’t tracking as planned. Plant testing in early July confirmed that the nil N plots (Trt 1) were N deficient and were requiring an N application whilst the banded Flexi-N plots (Trt 3)were tracking along with no issues. (Fig 4)
Fig 4.- NUlogic plant test results comparing nil N at seeding (Trt 1) to 100L/ha flexi-N banded at seeding (Trt 3)
This has three benefits :
a) Yield isn’t being compromised by loss of biomass through N deficiency
b) You aren’t forced to apply N in unfavourable conditions eg: dry periods, to try to fix an issue.
c) If the season does change you don’t have to try and play catch up by applying more which puts a strain on logistics and machinery.
• Efficiency Gains –
By banding Flexi-N at seeding we increased our Nitrogen Use Efficiency (NUE) which lead to the best return on our nitrogen spend. High stubble loads from previous crops can immobilise N. Studies have shown that 4-6 units of N/t of reside is needed for this residue to breakdown, effectively locking up or immobilising this N away from the growing crop. Following high yielding years 5-6t of residue is not uncommon. Banding Flexi-N places N away from the residue reducing the immobilisation effects. Banding N at seeding time also allows the young root system of an emerging crop easy access to readily available N leading to greater NUE. In this trial 100L/ha of Flexi-N banded yielded as high as 200L/ha of Flexi-N applied at Z31 using streamer nozzles. From a $/ha point of view this meant we doubled our return on investment in N (ROI) from $3.10 /kg N with a foliar application to $6.20/kg N for banded.
Fig 5.- Banding Flexi-N increases NUE and ROI
• Maximising Profit –
Optimising both yield and protein using current practise was still an issue. By applying additional Flexi-N in season to the banded plots by using streaming nozzles we were able to get to the maximum of 6t/ha but we still had issues getting our protein levels to the target of 10.5%. (Fig 6.)
Fig 6.- Additional N maximised yield but not quality using conventional practice
Fig 7. Additional N maximised yield and quality using a mid-row banding machine.
Fig 7 highlights that by utilising the mid row banding machine and placing this Flexi-N away from this high residue layer we were able to increase our yields with lower rates of N thus increasing our NUE as well as optimising protein levels on the high N treatments.
Whilst using a mid-row bander is definitely showing good responses here in plot trials I wouldn’t be rushing out to buy one just yet. A lot more work is required to see if it can be used efficiently and cost effectively in the WA environment across larger hectares. CSBP is continuing to work in this space with a bigger focus on improving NUE going into 2019.
My recommendations for 2019 would be:
1. Soil test to depth and know what is in your soil, without knowing you can’t plan!
2. If you aren’t banding N at seeding you should consider starting. Flexi-N bar conversions are a low cost investment that can bring big gains.
3. If you are already banding consider using higher rates especially in high yielding areas.
4. Be prepared to push the envelope with higher N rates. You don’t have to do all of your farm, have a go on some of your farm and see what rates work best for your situation.
As always contact your local CSBP Area Manager or Agronomist to find out more about this trial or others that we had across the state in 2018.
Thanks go to Nigel & Lynn Norwood from Kinliavan Farms for hosting the trial.