- Farmers Guardian
When transitioning from deep cultivation systems to min till or direct drilling, care must be taken to ensure drills were adjusted to take account of differing soil conditions explained Dick Neale, technical manager at Hutchinsons.
He said: "In year one, soils are not aggregated if they have been in deep till for ages with no cover crop and heavy weather over winter washing out the surface.
“You end up with a slot through [when drilling] and soil comes apart in blocks which you have to close again. Closure of the slot may need to be set aggressively in year one."
In year two of a soil improvement programme, cover crops may have been used and roots will have led to some soil aggregation with residues sitting on the surface, allowing water to percolate through, said Mr Neale.
"When you go through with the drill, the soil opens and closes more easily, and when the slot is closed it stays closed," he said.
"You can go more gently with the drill in that soil."
From year three onwards, roots in soil were playing more of a role in binding it together and letting it aggregate, explained Mr Neale.
“With sands, direct drilling will work, but with clay loam it will not work well," he said.
"Plain press wheels do not work well, as soil is like a spring mattress. The soil needs stitching back together. They need to be serrated, not smooth.
"You need to adjust drills year-on-year. Soil changes year-on-year, so what you need to do to it changes year on year”.