Case study
1 June 2020
Maintaining and improving soil health will always be a key focus for the British beet sugar industry. Sugar beet is planted in the spring and harvested in the winter, and plays an important role in the arable crop rotation supporting environmental stewardship and soil health. The industry invests over £2 million annually in the British Beet Research Organisation (BBRO) to improve every aspect of our agricultural practices and supply chain.
The benefits of sugar beet in the arable rotation
Sugar beet is an essential crop for many farmers and often plays a vital role in soil and crop health in the arable farm rotation. Sugar beet acts as a ‘break’ crop in the rotation, and this means it provides a break or a rest from the more intensively farmed cereal crops that dominate most arable rotations.
A break crop is sown to provide diversity to help reduce disease, pest and weed levels and improve soil health.
As a break crop, sugar beet ‘breaks’ the cycle of many pests, weeds and diseases, and without this, these threats could increase and ultimately could mean the land is unsuitable for growing some crops. Having sugar beet as break crop also reduces the need for pesticides.
The large amount of organic material returned to the soil by the tops of the sugar beet after harvesting also helps build up soil carbon and organic matter reserves - an essential part to the healthy functioning of the soil.
The average increase in winter wheat yield following break crops in northern Europe has been estimated at 24%, reinforcing the value of a break crop.[1]
Our 3,000 sugar beet growers often also take the opportunity to grow winter cover crops before drilling their beet. Cover crops have been shown to have a significantly positive effect on soil health. For example, British Beet Research Organisation (BBRO) cover crop trials have found that soils tend to be drier, less susceptible to compaction, earthworm populations are higher, the crops help to conserve and add nitrogen to the soil and their roots helps improve soil structure.[2]
Protecting the soil when harvesting
Our growers are very aware of the need to minimise soil damage and compaction as this reduces the performance of their crops. Our own agronomists work closely with growers and the BBRO to provide advice on this throughout the sugar beet campaign[3]. Machinery designers are also very aware of the importance of protecting the soil and developments in technology such as weight reduction and tyre technology are key design features of modern sugar beet harvesters.
As well as managing the sugar beet harvester, the management of the trailers used to move the beet is just as important and controlling the movement of these within the field is another integral part of how growers manage their soils.
Growers also manage the risk of soil damage by selecting fields carefully in relation to their harvest date. For example, targeting the heavier land with higher clay content for early harvesting when soils are more likely to be drier and less prone to damage and using the lighter sandy soils for later harvesting. About 60% of the sugar beet area is on sandy loam soils and less than 30% on heavy clay soils so this gives growers the opportunity to match soils types to harvest dates. In the rest of Europe, there is a much higher a proportion of sugar beet grown on heavier soils than in the UK.
To further assist growers, we supported a cross-industry project that mapped land in relation to the risk of soil compaction. This used the soil type and the expected rainfall to model susceptibility to different vehicle weights.[4] The BBRO has mapped land across the sugar beet growing area in relation to the risk of soil compaction, with expected rainfall also taken into account by the model. This ensures growers are aware of soil susceptibility to different vehicle weights, and are able to tailor their approach accordingly.
Transporting the sugar beet to our factories - minimising soil loss
Very little soil is delivered to our factories with the sugar beet and we put limits on the amount, measuring the soil received and reporting this back to growers.
As an industry, we take every possible step to minimise the amount of soil that leaves the fields with the beet. Beet harvesting, storing, and transporting practices are continually developing to reduce the amount of soil left on the beet. Harvesters are increasingly effective in removing the soil from the sugar beet during harvesting and increasingly sophisticated cleaning systems are being employed to remove soil on the harvester.
We process around 8 million tonnes of sugar beet each year and take in around 200,000 tonnes of soil. In line with our circular economy approach and sustainability commitments, we do not waste this soil and recycle it into high quality topsoil which is used for a variety of purposes including house building, landscaping and sports grounds.
Research and development on soil
Through the BBRO, we support research to ensure the industry is using the best possible practices when it comes to soil. Current work includes the Soil Biology and Soil Health Partnership, a five-year project to deliver the latest knowledge on soil health. The work carried out between the BBRO and the Agriculture and Horticulture Development Board (AHDB) aims to increase understanding of soil biology and develop a toolkit to measure and manage soil health. Findings from the research are regularly shared with growers by the BBRO.
[1] Break crop benefits in temperate wheat production (Kirkegaard et al 2007)
[2] BBRO cover crop trials 2019 https://bbro.co.uk/our-news-opinions/our-opinions/opinions-2019/cover-crops-role-in-soil-management/
[4] (Ready to harvest? How do you decide? A new tool to plan harvest according to soil conditions 29 By Miguel A. Gabarron, Patrick Jarvis and Jack Hannam: Beet Review 85, nos.3 article)