A laser-grading project was initiated this year at the Macalister Demonstration Farm, in central Gippsland, to improve pasture production and flood irrigation.
The laser grading is being done across 10.6 hectares, split into 12 bays.
The project will measure the production of autumn-sown annual ryegrass and cover crops, and gauge if using amendments can create a swifter recovery than current conventions over a three-year period.
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"The experience of farmer board members is that laser grading reduces farm productivity and profitability for three to five years, post-laser grading," Macalister Demonstration Farm executive officer and trial projects manager Jade Killoran said.
Commonly used amendments such as lime, gypsum and nitrogen: phosphorus: potassium: sulphur (NPKS) fertiliser will be assessed alongside compost, biological seed treatments and multispecies cover crops. Incorporation methods will also vary.
"Novel amendments such as compost, biological seed treatments and multispecies cover crops have not been formally trialled in the Macalister Irrigation District," Ms Killoran said.
"So this project will allow farmers to determine whether these approaches have ecologic and economic merit on-farm.
"Our research suggests the use of biological amendments may have positive impacts on soil structure, water infiltration and subsoil permeability, through the creation of carbon and stimulation of biological activity in the soil.
"We'll be measuring soil fertility, water utilisation and fodder yield in-crop."
A baseline soil test was done pre-laser grading on the brown clay loam. All samples were slightly acidic, with calcium measured slightly low and magnesium slightly high.
"There were no requirements for capital application of nutrients," Ms Killoran said.
The ryegrass was sown at 25kg/ha, the multispecies cover crop at 60kg/ha, with lime and gypsum spread at 2.5 tonnes each and NPKS fertiliser across all plots.
"Lime and gypsum are commonly used by farmers after laser grading. The trial is demonstrating incorporation methods," Ms Killoran said.
"Multispecies cover crops are included in the trial because they have been gaining popularity, and we wanted to gauge for ourselves if there are soil health benefits for dairy farmers.
"A diverse cover crop mix should improve water infiltration, relieve compaction, increase soil carbon and carbon sequestration.
"We have also incorporated compost into some of the ryegrass plots as a soil conditioner and OC contributor for medium and light soils."
Revive Compost is to be applied, at a rate to be confirmed, on one of the annual ryegrass trial plots.
The multispecies cover crop will be sown with biological seed coating.
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