We have just witnessed one of the driest summers and autumns in many years. Tillage farmers hardly know themselves, as winter crops went into the ground in such good conditions and the area planted increased as a result.
The dry weather has allowed many jobs to be completed on good ground conditions. Slurry and dung has been spread, autumn herbicides sprayed and hedge-cutting carried out and all have barely marked the ground.
Yet, ploughing for spring crops was not allowed until yesterday (December 1).
The ploughing ban was introduced under the nitrates directive to avoid a flush of nitrogen mineralisation from the soil when no crop was present and it therefore wouldn’t be used. This would, in turn, prevent pollution.
Keeping a green cover on soil can also protect it from the elements and help to reduce soil erosion.
Having tested thousands of soil samples for soil mineral nitrogen I am fully aware that it is a complicated element. The same area of soil could be tested for soil mineral nitrogen today and tomorrow and two very different results could arrive at each time.
Air temperatures dropped to 0°C on October 27 (measured at Oak Park) and went as low as -2.9°C on October 31. Little or no mineralisation takes place once soil temperatures fall to 5°C or below – daily soil temperature data was not available.
Actions and reactions
For every action there is a reaction. One rule does not automatically make the decision not to plough good for the environment.
For centuries people have ploughed in the autumn to allow the frost to till the ground. It’s not an old wives’ tale; it works. Frost helps to break up the soil naturally.
If soil is ploughed in the wet weather, or less than ideal conditions, it can turn over in a heavy clump or slab. If, like last year, the spring time is wet and mild then that soil won’t receive any frost and may also be difficult to dry out; when it does dry out – having been ploughed in less than ideal conditions – it becomes difficult to till.
Compaction may also arise and cause problems down the line for drainage and nutrient availability in the soil. Just like ploughing to a calendar, spreading slurry or dung to a calendar can also lead to soil damage.
Farmers making their own decisions
Land was still in very good condition at the end of October – when temperatures dropped.
If farmers had the power to make their own decisions they could have ploughed in October and November when ground conditions were suitable and temperatures were low – therefore soil nitrogen mineralisation would be at a minimum – and the soil would then benefit from the frost over the winter.
Farmer also have to be organised and get on top of work. Carrying out a certain amount of winter ploughing allows them to do this.
No doubt there is a large group of people out there who will say that farmers shouldn’t be ploughing at all. Min-till and direct drilling methods are no doubt good for the soil, but these systems do not suit everyone.
Some farmers can also be forced to plough to control certain weeds like black grass. Cultural control methods are a big part of integrated pest management strategies on tillage farms and ploughing is one of the methods which can help to reduce weed problems.
Mind your soil
Where farmers are ploughing they should be able to do it in an efficient way.
Our soil is being degraded faster than it can be regenerated and, by 2060, it is predicted that we will have run out of land to produce food.
The majority of farmers take care of the environment around them and make conscious decisions to improve the way they farm, but farming to a calendar doesn’t allow them to do so.