The fine weather over the new year and into early January was useful to catch up with spraying, as we had a full fortnight without rain – happy days.

Anxious to at least get the Astrokerb onto the oilseed rape, I went out in trepidation with the sprayer, not sure if it was possible to travel at all. It could be a recovery job.

But it was quickly made obvious to me what I have long known; min-till fields are typically firmer when ploughed fields are a complete no-go area. It also greatly helps if the tramlines were driven previously in good conditions.

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The difference between the two was very stark. You wouldn’t know the sprayer was out in the min-till fields and I ran the last few litres out on a ploughed field headland which was a swamp. The 3,000l Bateman is relatively light and on wide Trelleborg tyres so it wasn’t as if I went out with 5,000l on bike wheels.

It is, on our heavy flat land, the principal reason why I like min-till - the good trafficability it provides allied to the fact of how level the fields become when ploughing ceases. We seldom have rutted tramlines.

And of course, direct drilled (no-till) fields would be firmer again. But do remember our version of min-till involves soil loosening to 175mm which you might think would render the soil trafficability similar to that of ploughed land, but not so.

Ploughing, by its very nature, loosens the lot and loose soil holds water like a soggy sponge. But compress the sponge and it can no longer hold water. A firm top layer on the soil acts like a flexible metal roll-out road.

I’ve noticed intensively grazed sheep do something very similar to the soil; the surface becomes solid but underneath all is good.

And this was borne out last week in the wet weather; it was possible to spread slurry with the tanker on sheep-grazed ley while the other grass fields were a complete swamp.

It is for this reason direct drills need a soil penetration capability of 300kg of downforce per coulter. Underneath the consolidated surface, it’s not necessarily compacted and the roots keep the soil open.

The trick is to be able to place seed accurately in this ultra firm soil and to generate enough tilth to cover the seed and close the slot, eliminating slug motorways.

By its very nature, a disc coulter is best to do this or a narrow low disturbance tine coulter. Whilst in theory our Horsch Sprinter tined drill is suited to direct drilling, covering the seed uniformly, or even at all, would be the problem.

Furthermore, it’s a complete mystery as to how seeds emerge fairly evenly with a tine drill as it cannot follow the field contour. A tine coulter can only rise; it can’t lower into a hollow and seeding depth is largely aspirational. If I were to direct drill, I wouldn’t flute around with the Sprinter and probably have a Horsch Avatar disc direct drill.

So, you may well ask, why do we not direct drill? I like to incorporate stubble and chopped straw into the soil for more rapid breakdown.

Cultivation also destroys slug eggs. In earlier years, shallow min-till didn’t work particularly well for us and so some loosening is necessary, especially for barley. And stones won’t roll down in direct drilling but neither will a disc coulter pull them up.

Arguably min-till gives higher and more consistent yields but, on the other hand, maybe after 20-plus years of min-till, many of our fields are ready for no-till/direct drilling.

But machinery salesmen note; I’m not in that headspace yet – and may never be.