Sustainability in Arable Farming
Adam Christie, Managing Director at Scottish Agronomy
Agriculture is a fundamental part of Scotland’s economy and modern farming activities can have a profound effect on our landscape, communities, and diversity of landscape. Creating a sustainable agriculture business is growing in importance from both a social and economic context, and can be defined as one which avoids the depletion of natural resources, supports a healthy society, and remains financially viable for the long term.
For many farmers, the hike in fertiliser prices recently has focused attention on finding suitable alternatives to deliver commercially viable yields. According to the National Farmers’ Union, fertiliser prices have risen by 300% year-on-year, from around £250 a tonne to £600-£1000 a tonne, depending on product, leaving farmers in an increasingly difficult position. It can now take three times as many tonnes of wheat to pay for the required ammonium nitrate as it did as recently as 2020!
At Scottish Agronomy our research has been driven by this desire to maximise production in a prudent manner whilst protecting Scotland’s unique environment. Drawing on many long-term agronomy experiments, such as the 167 year Broadbalk experiment at Rothamsted, we can conclude that sequestration of carbon in an arable rotation is challenging. These invaluable long-term experiments show that an arable rotation reduced the soil’s ability to store carbon, compared to the pre-agriculture “wilderness” state.
With the pressure of feeding the eight billion mouths now on the planet, up from three billion as recently as 1960, the difficulty is going to be finding the balance between saving the planet and feeding the world. It is essential that growers maximise output from cultivated land responsibly to ensure that less suitable land is not forced into production as is currently happening to primal rainforest worldwide.
A century after the experiments began, it was found that the amount of organic carbon (C) in topsoil (0-23 centimetres) was substantially improved by having grass in the rotation or using FYM. Straw chopping was found to improve carbon deposition, but only by 3% over a 22-year period. In order for the soil on our farms to remain healthy and productive we must maintain reasonably high levels of soil organic carbon. The best way to ensure this for today and for future food production is to carefully manage farming techniques, inorganic fertiliser usage, and crop rotation.
Pressure on the industry to reduce emissions has also come from the Scottish Government as they seek to match Scotland’s climate commitments as well as powerful multinationals such as Diageo and PepsiCo who have indicated a switch to sustainable procurement policies.
These new challenges call for new services for arable farmers and we are offering our Scottish Agronomy members benchmarking and carbon auditing as part of this to support their changing needs. We are also committed to finding solutions which will benefit the farming community and facilitate continued successful Scottish farming for the future.
New research on fertilisers made from sources such as waste potato are proving promising. Their pelletised form makes application efficient using conventional farm equipment and results are looking positive as an alternative to conventional inorganic methods.
Trials with beans are ongoing but have also brought encouraging results, and this year we will have five geographically-spread test sites to test the geographic suitability of winter-sown of spring beans. This winter has certainly been a real test so far for winter hardiness. Cover crops are not a new concept but are a very useful crop for the modern farmer. They can be used as a means of retaining fertility in a rotation, improving soil structure and drainage, and providing a habitat for beneficial wildlife for pollination and pest control. However, beware of unintended consequences such as Brassica inclusions increasing clubroot risk or Phacelia increasing Free-Living Nematode numbers. We have found that, as with any other crop, careful planning is essential when sowing cover crops to secure the best results.
We have been involved with a very successful project at Balgonie Estate to encourage brown partridge breeding pairs by increasing biodiversity of the farmland. The use of wildflower strips comprising of a mixture of herbaceous species was sown on arable field margins encouraging insects which feed partridge chicks and provide cover for them in spring and early summer. Flower strips have several ecological, agricultural, and conservation benefits. Limiting pests and increasing pollination are perhaps the most important for a thriving business and studies have shown that flower strips constitute a preventative measure to control pests in both potatoes and cereal crops when coupled with other plant protection measures.
Winter Rye is fast becoming a legitimate alternative cereal option due to reduced input levels, uses 25% less water per tonne of grain produced compared to wheat, and produces higher yields at lower nitrogen levels than comparable cereal crops.
As I discovered on a recent fact-finding trip to Denmark, the issue of sustainable arable farming is complex, far reaching, and vital for the health of our sector, communities and the planet. We still have a lot to learn about how to tackle this issue and the challenges are great but if we follow the example of the Danes and work cooperatively and with a strategic plan to find real solutions that conserve natural resources, support society, and maintain profits, we will continue to have a thriving agricultural sector in Scotland.
