New carbon, liquid fertiliser trials show strong benefits
INTEREST is building towards grain yield results from another year of trials investigating the performance of a range of new carbon products and high concentrate liquid fertilisers across the State’s agricultural region.
Carbon Ag is coordinating the trials from Latham in the northern wheatbelt through to Kulin in the eastern wheatbelt, south to Borden and across to Esperance in the south east. The company has engaged independent research businesses, SLR, a new development and extension research entity, and South East Agronomy Research, to manage fully replicated plot trials at the Liebe Group site at Latham, as well as at Tammin and between Wittenoom and Neridup in the Esperance region.
The trials feature pre-seeding, seeding and foliar applications of a range of products, including:
WA Broadacre Blend loose carbon, which suits soil amelioration programs.
C33 carbon pellet drilled at sowing.
Liquid phosphorus and potassium fertiliser, DKP, which is also in Council of Grain Grower Organisations (COGGO) trials.
Immediately available calcium, magnesium and nitrogen product, CalMag.
Bioprime range of soil microbial stimulants.
Various applications with the products also are being compared alongside growers’ standard fertiliser programs.
Rob Hughes, South East Agronomy Research, said the fully replicated trials on Mic Fels’ property in the Esperance region included the C33 pellet applied at 30 kilograms per hectare and 50kg/ha along with DKP at 15 litres/ha and Bioprime at 4L/ha. These are being compared with the standard fertiliser practice of K-Till at 100kg/ha and Flexi-N at 75L/ha. The 30kg/ha C33 treatment is also being applied with half of the standard practice, comprising Agstar Extra at 50kg/ha and Flexi-N at 40L/ha.
Carbon Ag also recommended two applications of DKP, CalMag and Bioprime be applied to all C33 treatments at the Z31 and full flag leaf crop stages.
Rob, who farmed in the wheatbelt and at Scaddan over 25 years, said the C33 treatments established quicker and have been slightly more advanced throughout the season.
“The carbon treatments have grown equally as well as the farmer practice under the conditions. You could see that they were tracking along a little better and the visual differences are still there. They came into head sooner and will finish sooner,’’ Rob said.
Pictured earlier this season shows wheat establishment under a standard fertiliser program at Gavin Broun’s property near Coorow.
Pictured shows the establishment of wheat on Gavin Broun’s Coorow property sown with the C33 carbon pellet as well as DKP and Bioprime liquid products from Carbon Ag.
Barlock lupins on the Stone family’s property near Borden sown with the C33 carbon pellet as well as DKP and Bioprime liquid products from Carbon Ag (on left), compared with the standard nutrition program (on right).
Josh Mackie prepares to weigh some plant samples taken from the Carbon Ag trial on the family’s property near York.
“I thought it may run out of legs, but it hasn’t and it looks like a reasonable crop. I was a bit surprised with how many heads came through despite the late sowing (early June) and considering the biomass that was there. The heads are pushing four wide and some five. I wouldn’t have expected it to be filling as well as it is.’’
Michael Lamond, SLR, said a range of replicated DKP treatments were being compared with standard fertiliser practice at the Liebe Group site on Dylan Hirsh’s property near Latham. Carbon Ag also carried out foliar applications of its liquid fertiliser products over the DKP treatments.
Michael said early growth differences were very evident and were confirmed by biomass accumulation assessment tools.
He said the differences had since flattened during the season and interest was now turning to harvest yields.
Dr Peter Keating from Bioscience, which is undertaking independent analysis of the trials, said one of the strongest differences compared with grower’s own nutrition programs this season was significantly increased plant weights, particularly where foliar treatments of DKP and Bioprime followed seeding applications.
“By improving crop nutrition with these products, what is clearly showing up is bigger plants,’’ Peter said.
“Leaf tissue analysis doesn’t necessarily show increased nitrogen, phosphorus or potassium uptake by the plants as a percentage of dry weight, but they can be taking 50 per cent more out of the soil because they are considerably bigger.
“How the bigger and healthier plants then translate to yield at harvest depends on rainfall in the different areas.’’
He said across all trial sites, the Esperance area had received good spring rainfall.
The leaf tissue analysis did show some higher uptake of phosphorus and potassium where higher foliar rates of DKP and Bioprime were applied, while in some standard fertiliser programs, it indicated higher nitrogen levels than required, which can be inefficient and cause increased disease and pest pressure, as well as reduced organic matter.
In-season soil carbon levels followed a similar trend to last year’s trials, with significantly increased soil carbon detected in areas where the C33 pellet was drilled at sowing. Soil carbon levels will be further assessed in early 2021 using Veris on-the-go soil sensor technology, supported by ground-truthing.
Brad Wisewould from Carbon Ag said sites where the C33 pellet was drilled for the second consecutive year, and which were experiencing a dry finish to the season, were demonstrating crop benefits.
“In areas like Kulin, crop in the C33 sites benefitted from better moisture retention, hanging on for longer and with greener heads, whereas tipping occurred in areas that received standard nutrition due to the dry conditions, which have affected many parts of the cropping region,’’ Brad said.
“As soil carbon is building, it is also improving the availability of nutrients, some of which are tied-up. Applications of these nutrients then don’t need to be so heavy.’’
Overall, he said crops that received the carbon and liquid products, which involved a similar investment as standard nutrition, showed better root systems, biomass production, flag leaf retention and persistence with less pest and disease pressure, as well as with larger heads and improved grainfill.
Brad said the quickest and greatest crop establishment across the trials was derived from seeding applications of C33 at 30-50 kilograms per hectare with DKP at 10 litres/ha and Bioprime at 4L/ha.
“DKP looks to be a good fit in WA agriculture with the strong adoption of liquid sowing systems, the fact that its phosphorus and potassium is available immediately, and to avoid the salt element associated with the soil reaction of compound fertilisers.’’
“Bioprime drives plant health and soil biology, and growers have also found better uptake of foliar herbicides by including a litre of it in their tank mixes.
“Calcium demand also has been highlighted in some leaf tissue results, so CalMag has been applied at two to three stages throughout the growing season.’’
In addition to the soil carbon measurements, three rounds of NDVI and Taranis imagery looking at seedling emergence, biomass production and weed, disease and pest pressures has been collected from the trials this season.
A full trials report with yield results and return on investment calculations will be available from Carbon Ag after harvest.
Brad said the company looked forward to continuing its research and development with the products and he said a limited 2000 tonnes of the C33 carbon pellet would once again be available to growers for the 2021 season.