Building Great Soils

Worldwide there is an increasing focus on improving our soils whether that is improved resilience and less erosion or improved yields, a constant theme is soil organic matter and how to increase it.  Whilst organic farmers advocate this or that approach and regenerative farmers argue for their solutions, there remains one overriding objective that of increasing below ground life.  Achieving meaningful and beneficial outcomes from this simple starting point is the challenge facing farmers.  Whilst there is a temptation to argue that the problem is overwhelming and the solution difficult to achieve there are for most situations a few easier options.  Five key issues have been identified as a means to improving soil fertility.  Very few farmers will be able to undertake all of the options but selecting a combination of the options is likely to bring faster and greater rewards.

1. Reducing disturbance – Physical disturbance (cultivation) obviously kills roots and a lot of below ground organisms.  On the other hand, herbicides that kill the above ground biomass and as a consequence the below ground roots die, have a similar effect on the below ground environment.
Whilst reducing tillage has become the mantra of the direct drilling and reduced tillage brigade of arable farmers and has shown tremendous benefits in terms of reduced soil erosion and nutrient loss, it has required new skills, patience and in many cases a deep pocket to implement.  For grassland farmers with grass leys it remains an easy win and we all know the benefits of a grass break crop in arable rotations.

2. Maintaining plant cover has clear benefits, as it reduces the risk of erosion and helps to lock up nutrients left by the previous crop and is being supported by government with payments for cover crop or catch crops.
The benefits are being widely reported for many cropping circumstances with easier working soils and improved or easier weed control.  At the same time opportunities are being missed to have over wintered cover crops.  Late harvested root crops and maize can pose a challenge for farmers looking to establish an over wintered cover crop.  Rapidly establishing rye or phacelia may fill the gap.

3. Increasing diversity which has been the call from the diverse swards brigade.  Certainly, introducing clover legumes and herbs into swards offers an easy option.  The evidence of the benefits from these swards in terms of total production are now becoming well documented in low input and organic systems.  Recent work has shown this approach can be as productive as using up to 200 kg/Ha of nitrogen in a grazing system.  Wholecrop forages including peas and other legumes offer an opportunity to replace some of the maize silage in diets.
For many farmers the question remains about the animal performance on these systems.  The long-term trial at the University of Reading is aiming to answer this question.
Increasing diversity in arable systems is far more of a challenge and for many will need a systemic change in farming systems if it is to be fully embraced.  A starting point has been the introduction of spring crops and the use of cover and catch crops over winter as well as extending the rotation with more break crops.  To become fully diverse will require the growing of different species at the same time and the interest that is currently being shown in under-story crops is a step in this direction.

4. Reducing synthetic inputs.  It is now widely accepted that many of the inputs that we have long believed to be crucial to the success of our business and have become reliant on, have detrimental effects on the below ground environment and thus on efficient nutrient cycling.
For a growing band of arable producers reducing the use of seed dressing which not only provide protection against soil borne disease but also destroy the beneficial biology which plays an important role in nutrients cycling.  The more diverse a rotation, the lower the risk that a soil borne disease will need an expensive seed dressing.

5. Introducing grazing livestock.  The benefits of a grazing animal on improving soils is now becoming clearer.  Not only do they make nutrients available from plants they introduce their own range of microbes into the soil, which helps to break down dead material in the soil into more readily available nutrients.  The opportunity offered by the introduction of cover crops that can be grazed on arable farms is being shown by the increasing number of opportunities for new entrants to being livestock onto arable farms.

The benefits from improved soils are clear, however it can be a daunting task to know where to start.   An ideal place can be with the more difficult fields where the losses may be lower.  Reviewing the options and preparing a plan is critical.  Starting with the simple and cheap cover crops or catch crops is a low risk strategy.  With experience and confidence gained from this, plans can be modified and accelerated.

Contact William at w.waterfield@fcagric.com to discuss this in more detail and help you start formulating a plan to increase your farm’s soil biology and organic matter.

Posted in Andover, Arable & Crops.