NEW SAGIT trustee Ted Langley says he’s no scientist, but he can still see major crop improvements from minimal soil disturbance at his 3200-hectare Bordertown property.
Subscribe now for unlimited access to all our agricultural news
across the nation
or signup to continue reading
Mr Langley was a guest speaker at the recent SA No-Till Association conference at Tanunda, talking about the progression of his family’s property into a zero-till, controlled traffic farming system.
One of the more important moves was the switch to a disc seeder in 2008.
“Soil cover is the main focus behind soil conservation on-farm, to leave crop residues on top, and the best way to manage that is by using discs,” he said. “With knife points, the tynes can’t handle residues as well as discs.”
Mr Langley admitted discs required more maintenance than tynes, which were easier to “set and forget”.
“Discs change with the conditions you put them in, and they must stay sharp to handle residues,” he said. “But if you inter-row sow, then there are hardly any residues there to contend with.”
Mr Langley said low disturbance by discs meant that soil aggregates, such as worm channels and old root channels, avoided damage.
“My knowledge on soil biology is not great, I can only observe the things I do, and a simple one is the increase of worm castings,” he said. “I can see them when I dig into my soil, plus how the roots of the new crop follow those pathways down into the profile.”
Mr Langley said the improvement showed in their yields in dry seasons.
“The yields are about the same in dry years as what we would have once got in a good year using the old methods,” he said. “But this way, we know that we are improving the soil profile and our roots are tracking deeper to find moisture.”
Mr Langley, with his brother Bill, crops beans, canola and wheat in that rotation to ensure plant and chemical diversity.
“We used to grow back-to-back cereals, but ryegrass became an issue, as did the concern about chemical resistance, so we try to rotate chemical groups as much as we can,” he said.
They also use narrow row spacings of 7.5 centimetres, to increase canopy coverage.
“Sunlight is wasted hitting bare ground and heats the soil, taking away the moisture,” Mr Langley said.
The Langleys have also grown summer crops, such as sorghum and sunflowers, for the past six years, to further increase plant diversity and groundcover in the hot months.
“We aim to harness summer rainfall instead of letting it evaporate,” he said. “In our environment, any rain from 10 millimetres to 70mm in the profile will evaporate across the November/December period. Why not try and use something that will disappear anyway?
“And if we can capture the carbon in the soil, open a root channel, then that’s exactly what we want to do.”
But the results, particularly in the past two years, had not been as ideal as hoped with insufficient spring/summer rainfall.
“So this past summer, we didn’t have the confidence to grow them,” Mr Langley said. “If the seasons turn back to some sort of normality, then that’s what we aim to do.”
