WHEN harvesting a newly-purchased property in 2011, Kimba cropper Trevor Cliff said his yield monitor did a strange thing.
“The previous owners had spaded a small patch of the paddock several years earlier, so every time the harvester went across that ground, the yield monitor would go berserk (increase dramatically),” he said.
Despite previously hearing about the benefits of spading, Mr Cliff was hesitant because of the expensive clay spreading they had recently undertaken.
“But the results were too good to ignore,” he said.
A spader is a digging machine that mixes soil thoroughly up to 40 centimetres, enabling the incorporation of clay, stubble, green manure, fertiliser and/or trace elements.
Early last year Mr Cliff said they decided to invest in their own Farmax spader, with their clay spread paddocks the first target.
“The aim was to incorporate that clay band deeper into the soil,” he said.
They followed the spader immediately with the seeder last season, with the risk of soil erosion in mind.
“The process still technically works up the ground and we wanted to avoid drift, so we made sure there was enough moisture to allow the crops to establish and stabilise the soil,” Mr Cliff said.
They spaded about 140 hectares in the first year, mainly sandy soils, which were sown to Kord wheat.
At harvest, the spaded paddock yielded an extra 0.5 tonnes/ha to 0.8t/ha, which encouraged Mr Cliff to proceed.
They have since spaded more than 300ha, with mainly clay and organic matter, but also some trace elements including copper and zinc.
But spading is a process that will require further fine-tuning.
“We are still trying to find out whether different soils prefer different spading depths, whether lighter soils prefer shallow spading, because of it being prone to erosion, so we still have a lot to learn,” Mr Cliff said.
“We have been lucky the past few winters in that crops have emerged quite quickly, reducing the chances of drift, but that may not happen every year.”
Mr Cliff said the ultimate goal was to spade and seed at the same time. “It is expensive to set-up so we will look more into it in the next two to three years,” he said.
The previously spaded wheat paddocks were sown to lupins this year, to compare with non-spaded lupin paddocks.
Mr Cliff and wife Kerri, with fourth-generation son Randall and long-time farm assistant Trevor Clifford, crop 4200ha of owned and leased land near Kimba. The no-till operation includes wheat, barley, lupins, peas, canola and oats for export.
New varieties were being trialled on-farm this year, including Sceptre wheat, which is grown alongside longer-growing Cutlass, Clearfield Kord and high-yielding Mace, while new barley variety Spartacus will be grown alongside Scope – “Clearfield varieties to help us manage bromegrass”, he said.
The season is going well, with 50 millimetres to 90mm of rain before seeding and 140-150mm so far for the growing season.