Carbon pellets show promise

Kate MatthewsCountryman

Great Southern grain growers have been given a snapshot insight into the benefits of using organic carbon pellets as part of their fertiliser program during the growing phase.

At a resilient soils workshop in Katanning last week, farmers and Landcare project officers found that when organic carbon pellets were used, plant roots were healthier, stronger and retained more moisture.

The trial, funded by the South West Catchment Council through the Federal Government's Caring for our Country program, was co-ordinated by the Blackwood Basin Group (BBG) to combat wind erosion.

Four sites near Katanning compared the below-ground performance of normal fertiliser rates against sites where a mix of 50 per cent of fertiliser and 50 per cent organic carbon pellets called Balance were applied. The pellets are made by Custom Composts and have been used across the State after eight years of research and trial work.

Custom Composts director Dave Cullen said that by using Balance, growers could improve their plant root mass, giving plants greater resilience to hang on between rainfall events.

Agronomica agronomist Deb Archdeacon said that before planting, soil samples at all four sites were analysed for soil chemistry and biology and retested six weeks after germination.

"The results were different on all properties, but generally the amount of available phosphorous and potassium rose in the soil even though only half the rate had been put on," Ms Archdeacon said.

Tissue analysis showed no significant nutritional difference between the control and treatment crops.

While the trial was focused on the growing season, researchers and the BBG hope to secure funding for a five-year trial to include yield and quality analysis.

Katanning grain grower Adrian Richardson trialled Balance on an oat crop inspected by the group during the workshop.

Adrian set up three comparisons - a control with 80kg of Agflow, one with 40kg of Agflow and 40kg of Balance, and one with 70 per cent Agflow and 30 per cent Balance.

"Visually they look pretty much the same and it's difficult to tell the difference in my opinion," he said.

"I'd like to find an alternative to chemical fertiliser and something to enhance the soil."

At harvest, Mr Richardson will compare yield and quality.

BBG's Kathy Purvis said the main driver for organic carbon pellets was to improve soil structure and long-term soil health.

"The organic carbon pellets are small and are applied through the airseeder so there is no extra fuel or time used," Ms Purvis said.

"When compost has been trialled before, it had to be broadcast during the cropping phase and it's an extra movement so that's one of the reasons the pellets were trialled.

"It's got to be realistic. Farmers won't use uneconomic methods and that's why we've made it a comparative trial."

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