UK cover crop champions unveiled by AHDB

Friday, 20 September 2024

A network of cover crop champions has been convened by AHDB Cereals & Oilseeds to provide practical case studies on the impact of cover crop approaches.

Following on-farm trial design principles, each of the eight champions is establishing a cover crop ahead of various cash crops for harvest 2025.

Supported by AHDB, the champions will record core measurements and observations to help assess the impact of their varied approaches.

First pioneered in the US, cover crop champions tackle the complexity associated with cover cropping and share their experiences with other farmers.

What will the champions do?

Ana Reynolds, Head of Sustainable Farming and Research at AHDB, said:

“Cover crops can have many environmental, soil, crop and economic benefits. The best approach will depend on the farm’s objectives and how well the cover crop fits into the system.

“The champions will use a common trial protocol and document their approaches – from the mixes used to the way cover crops are established, grown and terminated. By sharing their successes and failures, we want to help other farmers on their cover crop journeys, build on the work at our Strategic Cereal Farms and Monitor Farms and inform the development of decision support tools.”

Each champion will follow AHDB’s five steps to cover crop success:

Identify the aims and objectives
Grow a few options (including controls, where possible)
Monitor and record progress
Evaluate the response
Respond to the evidence

Most of the champions already have several years of experience and want to take their approaches to the next level.

All champions will include assessments of nitrogen (in the soil and the crop) to help determine the influence of cover crops on nutrient dynamics. How to estimate the availability of nitrogen to the next cash crop following a cover crop is a key question.

Following the wet 2023/24 growing season, soil condition was relatively poor at many of the commercial sites when the cover crops were established in autumn 2024. The initiative provides a good opportunity to measure how cover crops help soils recover compared to the no-cover-crop controls.

Meet the champions

During summer 2024, the AHDB Cereals & Oilseeds Knowledge Exchange team recruited cover crop champions based on AHDB regions while capturing a wide range of systems and approaches within the UK network.

As part of the initiative, AHDB will also highlight cover crop approaches taken by other farmers.

Scotland

David Fuller-Shapcott, Sweethope Farm, Scottish Borders

With his heavy land prone to waterlogging, David has used cover crops and reduced tillage for several years to improve soil health, including organic matter levels. In Scotland, establishing cover crops is a particular challenge. This trial will examine if a biostimulant seed treatment (based on endophytes) can improve the germination and establishment of two simple cover crop mixes.

Northern Ireland

Chris Gill, Caledon Estate, County Tyrone

Chris has used cover crops for several years, broadcasting seed into forage maize stubble to help hold the steep and hilly terrain together and get spring crops off to an earlier start. In this trial, he will broadcast hybrid kale into the stubble in one pass (with the help of a nine-leg grubber). The land will be split into blocks to investigate the impact of grazing by sheep (provided by a local farmer). A no-grazing block (control) will be compared with two grazing blocks – the first grazed relatively hard and heavy, the second grazed more lightly (potentially providing the option for a second graze on the regrowth). Chris hopes to demonstrate the benefits to other farmers, as cover crops are not being widely used in the area.

North East

Robbie Stephenson, Crawleas Farming, County Durham

Robbie grows potatoes in his rotation, which also includes barley, wheat, oilseed rape and winter beans. The farm also has some livestock (sheep and pigs). He uses cover crops before potatoes to condition the soil. The trial field is coming out of barley with the cover crop combination drilled into the stubble to get the cover established quickly before the weather turns. The cover will be in until around March before the potatoes are planted. Traditionally, he has used a mix of black oats, vetch, clover and phacelia. Now the mix has been tweaked to boost the biomass available for sheep grazing. The new mix is heavy on buckwheat, with the vetch component also increased. He has reduced the phacelia (due to its nematode interactions). Robbie has ordered the seed as straights and will make the mixes on the farm. A split-field trial will compare the new cover crop mix with the traditional farm standard cover crop mix and no-cover area.

East Midlands

Ian Matts, Brixworth Farming, Northamptonshire

Although Brixworth Farming continues to focus on winter wheat, the rotation has been diversified in recent years to help get on top of black-grass. More spring crops are now grown, with non-cereal-based cover crops (with a mix of root architecture) in place over the winter. With the legume species fixing nitrogen and the buckwheat scavenging phosphorus, Ian wants to better quantify how the cover impacts nutrient availability. The farm has incorporated sensors to track nutrients and moisture in the two trial fields (with similar properties). One field has a no cover (control), whereas the other includes the cover crop (sown with a one-pass subsoiler machine to help loosen the wet-season-challenged soil to get the cover crop rooting). The farm is also integrating SFI options into the rotation, such as legume fallows in NUM3.

East Anglia

Jonathan and Jane Clarke, Bury Farm, Great Canfield, Essex

Bury Farm has been in the hands of the Clarke family since the 1920s. The rotation features winter wheat, borage, spring barley and canary grass. They also have a herd of Red Poll cattle. They are part of an active farming community that works together to increase biodiversity and improve the local river catchment (the farm is near the River Roding). The team is relatively new to cover crops, which are being used for the second year. The farm’s rotation provides plenty of opportunities for short-term cover ahead of spring crops. In particular, the Clarkes are testing various establishment techniques to identify the best approach for their farm.

South East

Rob Waterston, Welford Estate, Newbury

The Welford Estate has used cover crops for several years to build organic matter. Rob now wants to better understand the impact on nutrient dynamics, especially to reduce nitrogen inputs to following crops. Typically, the farm standard nitrogen for spring malting barley is 110 kg/ha. The trial field is coming out of spring barley, with straw chopped and spread during combining. A strip till machine has established the cover crop mix (buckwheat, phacelia, berseem clover and radish), which provides a good mix of root architecture and strong biomass (with the potential to graze sheep). Rob will destroy the cover in late winter (January or February) before planting a further spring barley crop.

South West

Bob King, Lower Baynton Farm, Wiltshire

Lower Baynton Farm covers about 250 ha, 200 ha of which is arable. Cover crops are grown on 60 ha of the arable land. The farm uses a diverse, multi-species mix, comprising berseem clover, phacelia, vetch, buckwheat and brassicas (forage rape, stubble turnip and kale). The cover crops are raked into the soil soon after harvest and are grazed by sheep throughout the winter, before spring crops (oats, barley or beans) are direct drilled. Bob has used cover crops over a decade to protect the soil. He is eager to quantify the wider benefits, including to soil health and nutrient availability.

North West

Charlie Copley, Reaseheath College Farm, Cheshire

Charlie (Arable Foreman) will explore how cover crops can help protect the soil and aid structure recovery after a maize crop. The trial will compare various cover crop mixes with an area left to overwinter stubble (the no-cover-crop control). What makes the approach unique is that the trial will underpin discussions with students on the role cover crops play in soil health.

Initiative background

The need for independent cover crop information is frequently raised by farmers, especially to help them diversify income, such as through the Sustainable Farming Incentive (SFI), and is cited in the AHDB Cereals & Oilseeds sector plan 2022–2027.

Cover cropping was one of the first topics considered by a new farmer-led AHDB Cereals & Oilseeds research and knowledge exchange (R&KE) committee at its inaugural meeting in May 2024. It led to the AHDB Cereals & Oilseeds Sector Council committing up to £60,000 to fund cover crops work.

Up to £20,000 is being used to support the cover crop champion network, with the remainder invested in evidence-based reviews to document the longer-term impacts of cover cropping – including to nutrient availability and soil health – and termination methods. The funds also cover the production of guidance materials.

Additionally, in 2023, the creators of the Cover Crops Guide and AHDB agreed to work in partnership to provide evidence-based information.

The guide’s expert steering group identified priorities to develop the guidance, including the provision of practical case studies, which the cover crop champions will deliver.

Yorkshire farmer Angus Gowthorpe, who led the first phase of the Cover Crops Guide (with funding from Innovate UK), said:

“The Cover Crops Guide provides independent information to help farmers select, establish and terminate cover crops. It was co-designed by farmers with the help of the Yorkshire Agricultural Society’s Farmer Scientist Network. The AHDB-funded cover crops champions align with the guide’s practical approach and will further strengthen the practical, independent information available to farmers.”

Each champion will chart their unique journey during the 2024/25 growing season via the AHDB website and social media channels. Several champions have already outlined their approaches in a suite of videos.

Cover Crops Guide

More experiences

As part of the initiative, AHDB will also document the experiences of other famers, such as the approach taken by Anthony Becvar.

Anthony Becvar, Little Goldsmith Farm, East Sussex

Anthony is using more year-round cover crops. The soil is mainly Wealden clay, which can go from too wet to too dry quickly. He uses diverse cover to improve the soil’s resilience, with long tap roots helping to break soil pans naturally. The cover also supports direct drilling better on his land rather than sowing into cereal stubble. Soil is central to his regenerative ambitions, but he has had mixed results with cover crops. He usually plants them after harvest, with local sheep grazing the cover through the winter and cattle grazing it through the summer. The trial field, which is in a two-year SFI scheme, will test two contrasting mixes. The first includes fodder radish, buckwheat (which shot away quickly but will get knocked back by the cold) and linseed. The second includes rye (which is a target for the farm’s slugs), radish, mustard (which is a target for the farm’s flea beetles) and vetch.

Cover crop trial is up and away! @cereals_se @TheAHDB @sewateruk pic.twitter.com/VQzMEaX2wg
— AnthonyBecvar (@anthonybecvar) September 12, 2024

Strategic Cereal Farms

Our Strategic Cereal Farms are also learning how to make cover crops work for their businesses. In this autumn 2023 webinar (recording and blog), find out how keeping the soil covered with a range of living crops and reducing cultivation intensity significantly reduced field nitrate losses. How cover crops influence numerous measures of soil health and biodiversity are also discussed.

How Strategic Cereal Farms evaluate cover crops (blog)

Additional answers to questions raised during this webinar

Strategic Cereal Farm Conference 2024

Join Strategic Cereal Farm hosts and their research partners to discuss the latest on-farm trial results in North Yorkshire on 7 November 2024.

Topics include cover cropping, nutrient use efficiency (NUE) and mechanical weed control (and much more).

Strategic Cereal Farm Conference 2024