I have long been advocating the imperative to match cultivation strategy to soil type as in the schematic below.
The photographs later in this article highlight this concept really well. They certainly demonstrate what the cost is of implementing inappropriate cultivations / misaligned cultivation timing / or the misguided strategy.
Soil type should not just be restricted to ‘texture class’ – light, medium, heavy, soil. But needs to be expanded to the added precision of ‘texture group’ – silty clay, sandy loam, sandy clay loam etc. This then highlights the constituent parts of the soil and provides a more accurate guide on how to manage the soil, and probable machinery to drill profitable crops.
The texture group is then further affected by the proportions of the cations in the soil. This is especially true of clay soils that have a high magnesium content, as this combination exacerbates the negative effects of the small clay particles on soil structure. This then further restricts cultivation timing options, especially when the weather conspires against you!
Data is crucial
Generating actionable data is the key to success. If you do not know what is happening in your soil then it is unlikely, nearly impossible, that you will be able to invest in appropriate machinery to generate profitable crops.
Consider the picture below:
The soil type in this field is Clay Loam, increasing to clay at the bottom of the hill. The clay particles will have been washed through the soil profile over the decades and the topography of the field has encouraged this gradual progression of the clay down the slope through the soil profile.
Both are ‘heavy’ soil classes that will at best restrict timing for cultivations, which is further compounded by a high magnesium content and adverse weather patterns. Not an easy combination to deal with at the best of times and exceedingly difficult without generating actionable data.
The penetrometer in the photograph is for scale, rather than for indicating a soil reading.
If this were your field, I am sure that you would prefer to look at the crop potential in the right-hand side of the field, rather than the left.
Drill or no drill
If we now consider that the left-hand side was drilled utilising the historic annual farm strategy of many years standing of utilising a three-leg subsoiler running at depth behind a crawler, and then drilling into that. This has been carried out without utilising a penetrometer, or spade, to establish the physical need for subsoiling or establishing where the compacted layer is in the soil. And if there, at what depth the compaction is at.
The drill was a Trailed Weaving GD drill. I MUST STRESS that there is nothing wrong with this drill, far from it. Many of my farmers are happy with the results from this drill. But the point is that this good drill was utilised in a situation where it just could not perform because the soil had been killed by the subsoiling.
So, the farmer has spent £60 per hectare to subsoil the left-hand side of his land when apparently it did not need it. With an estimated workrate of 1.75 to 1.9 hectares per hour this was a labour of love that appears to have been detrimental to the crop.
The contractors charge for a one-pass tillage train (Weaving GD drill) for the left-hand side was £65 per hectare with a workrate of 2.75 to 3.0 hectares per hour.
The photo above is from the right-hand side of the field. Penetrometer reading was 45 cm (18 inches), and even then, it was moisture levels applying pressure, rather than physical soil pressure, than was generating the final reading. This good result was replicated across the field.
This part of the field was drilled by my farmer with a direct drill strategy utilising a Weaving Sabre Tine drill in mid-October. Later than ideal, but the landowner was stymied by the weather hence the urgent request. Right machine for the soil conditions.
The contractors charge for a one-pass tillage train (Weaving Sabre Tine drill) for the right-hand side was £65 per hectare with a work rate of more than 3.5 hectares per hour.
Worms aplenty
The photo on the left is what virtually every spade spit revealed in the right-hand side of the field.
Impressive numbers of worm species that were adding their beneficial soil cultivation attributes to crop productivity.
Conversely, there were virtually none in the left-hand side of the field. Epigeic and Anecic worms, with a few sub-surface living Endogeic worms to be found.
They were probably hiding from the freezing weather!
This is what the Weaving Sabre Tine coulters look like, right.
Minimal cultivation, delivering rapid establishment with robust coulters – the tines made slightly longer for the prevailing soil types and structure.
Assessing soil and utilising appropriate machinery to achieve a potentially profitable result. Certainly, the crop in the right-hand side looks more promising and for a significantly lower establishment cost.