Category: Case Studies

Soil Farmer of the Year 2023 – Farm Walk with Bronagh O’Kane

Written by Emma Adams on behalf of The Farm Carbon Toolkit

In a first for the Soil Farmer of the Year competition, in October 2023 our series of farm walks took place in Northern Ireland. A group of farmers, academics and industry professionals met at Drumard Farm, just outside Cookstown in County Tyrone, to hear from Bronagh O’Kane on how she is transforming her farming business with resilient soil at its heart.

Bronagh introducing the farm to the group

Having come back to the farm in 2020, Bronagh began a journey to transform the soil. Historically the farm supported continental cattle breeds with a high reliance on imported feed, Bronagh has transitioned this system to more traditional breeds managed on herbal leys and ever-increasing diversity grasslands. Utilising a rotational paddock system she has extended the grazing period so that cattle can be out by 4 weeks and soils are more resilient to the extremes of dry and wet weather. Bronagh has started producing vermicast and composting to improve soil biology; focusing on natural inputs and a softer approach with foliar fertilisers where needed to manage historically compact and imbalanced soils. The walk will provide the opportunity to discuss and demonstrate the practices undertaken at the farm and the ongoing challenges and successes that Bronagh sees in her system.

The beginning of the farm walk

At Drumard Farm, Bronagh was told she had poor soils and no doubt they are a challenge, with testing suggesting an average of 45% silt and 45% clay they are tight and sticky, with little aggregation or infiltration. As such, understanding what was needed for the soil to function better was a priority for Bronagh, with a great deal of research it was understood that the high magnesium, bacterially dominant soils were being held back by a mineral imbalance, compaction from big tractors and heavy cows. 

Inspecting the soil condition following the autumn rain

Changing the livestock system at the farm has been central to Bronagh’s evolving management. The cattle business has been streamlined, and as such the previous finishing and store systems have been stopped instead to focus on a suckler system with pedigree Charollais sheep. The sheep are high value stock, as Bronagh suggests there isn’t the acreage for a larger flock, instead, she buys in September before selling the ewes with lambs at foot in the spring and runs the rest of the flock throughout the year. This system works well as there is the housing space available over winter and also the sheep provide a good opportunity to clean up the last of the grass when it is too wet for the cattle to graze. Previously the farm also had Charolais cattle, but these have been restocked, reducing numbers from around 80 to 50 on a sucker system focussing on more native breeds such as Speckle Park, Shorthorn and Hereford crosses with an Angus Bull. Even with these changes, Bronagh found that those animals with a Limousin cross within the breeding still comparatively lost condition on the new system which is thought to be from underlying epigenetic traits. This has led Bronagh to source more local Shorthorn heifers which are better adapted to a grass-based system. 

Bronagh utilises plant diversity as an indicator of the status of the soil. The species that may dominate in a field or area can suggest what the underlying composition may be – chickweed for excess nitrogen, low calcium or high potassium or creeping buttercup thrives where there has been poaching, bare soil and a low pH. Like many farms, docks have historically been widespread at the farm, often indicating compaction and an anaerobic soil environment. Bronagh’s approach to dock management is to change what has historically not been working – sprays and topping – and instead let them grow and allow the dock beetle to get to work combined with a cut for silage around June. This understanding of what the plants are indicating has led Bronagh to stop spraying and minimising fertiliser use to zero, instead focusing on balancing the soil and improving the health of the biome. She explains:

“Biodiversity, long rest periods and grazing management can change soils – you’re not stuck with what you have”

Grassland management is central to how the business is now run. Bronagh has diversified existing grasslands into multi-species swards despite the testing conditions and low pH of the farm. On the walk, the group visited a newly established herbal ley that had been planted in a field that was pH 5.8.  

The newly established multi-species herbal ley

The 15-way mix contained species such as sainfoin, plantain and chicory and Bronagh has subsequently experimented with both cutting and grazing, which has led to discussions with contractors on cutting heights, timings and more to best maintain the sward. For Bronagh, managing these lays to allow the full diversity is important, with the understorey plants encouraged through the aforementioned considerations in combination with the paddock grazing system. Bronagh has experimented with the paddock grazing timings and methods, including grazing the cows on knee-high swards which resulted in moving them faster but increasing the size of the paddock as the cows were found to be trampling rather than eating following heavy rain. Bronagh suggests:

The definition of overgrazing is letting them get that second bite – it is so important for my fragile, shallow roots to rest”

In addition to the home farm, Bronagh also has a 30ac National Trust tenancy on a zero-input system supporting both a rotational grazing and cutting platform. For Bronagh, having the right livestock that will thrive on a grass based system is key to success. As such, she puts the heifers on the poorest fields to determine which animals will be kept as some breeding is adapted better to the system than others. 

The walk also incorporated learning more about how Bronagh is using vermicast to provide nutrition and balance to her soils. Vermicast, or worm castings is made by using worms to compost organic amendments such as farmyard manure, food waste, wood chip etc to create a soil conditioning fertiliser.

Worm farm whereby organic materials are broken
down to create the vermicast

On the farm, vermicast is used to provide nutrients, stabilise pH and also as a coating on any new seed that is established. Bronagh applies her vermicast through a sprayer after making a ‘compost tea’. The vermicast is added to a porous ‘tea bag’ within an IBC filled with water which is then agitated and aerated using a bubbler to extract the nutrients and beneficial organisms which vermicast contains, the resulting liquid is then applied to land to stimulate soil biology and provide nutrients. Bronagh is aiming for a 1:1 ratio of fungi to bacteria which the vermicast and good soil management will help promote.

Bronagh explains the process of using vermicast
to make a compost tea

Regularly conducting Brix testing has allowed Bronagh to understand how to best apply the vermicast and the benefit it is having to her land, with fields which have had no fertiliser, slurry or inputs other than vermicast scoring 12, with Bronagh suggesting that every 1% increase in a Brix result can give a 0.5-0.75kg improvement in liveweight gain in the cattle. Any amendments which Bronagh applied to the land are designed with this goal in mind, alongside the cost and feasibility within her system. An example of this is that she has been experimenting with using egg shells to help aid the calcium balance and flocculate the soil; this can be spread with a conventional fertiliser spreader rather than other products which can have additional costs due to the price of both material and the contractor required to apply the product. 

Since 2015, the Soil Farmer of the Year Competition has helped to find, promote and champion UK farmers who are passionate about safeguarding their soils and building resilient businesses. As part of the competition, the top three farmers host farm walks that bring farmers together to share good practice and innovations that improve soil health. The 2024 round of the competition opens on 5th of December 2023, which is World Soils Day – if you are interested in finding out more, entering the competition or nominating someone who you think is deserving of this award further details can be found on the Farm Carbon Toolkit website or https://farmcarbontoolkit.org.uk/soil-farmer-of-the-year/ 

Lessons Learnt at Erth Barton

Wednesday 18th October 2023

Tim Williams has now completed three years of a contract farming agreement with Antony Estates, working to convert Erth Barton into a regenerative farming system, rebuilding soil fertility. This event was a chance to hear about some of the successes and challenges encountered during the transition. This event was made possible with thanks to the National Lottery Community Fund who fund the Farm Net Zero project.

Tim took on the 300-acre (121 hectare) farm in two halves, arriving with very little kit and limited funds for inputs. This has meant he has built a simple, zero-input system focusing on restoring and feeding the soil microbiology in order to provide fertility.

A very diverse cover crop/herbal ley was drilled to increase rooting depth and diversity and then grazed with beef cattle (averaging 0.8 Livestock Units per hectare) with the aim to eat a third, trample a third and leave a third. Tim has learnt that it is best to focus on managing grass to build up a reserve rather than eating into it. Frequent moves leave grass to regrow, meaning there is always grass ahead of the livestock throughout the rotation.

Another method Tim has trialled to improve soil microbiology has been applications of compost created using a system called “complete microbial composting” developed by the Land Gardeners. This involves mixing brown (cattle dung, soil, straw) and green (fresh cut plants) material from around the farm in long windrows and turning. Three methods of application were trialled – direct spreading, compost tea brewing and “biopriming” (mixing compost with the seed prior to drilling). Tim felt that the biopriming technique has the potential to be the most successful. However, soil microbial testing conducted by the University of Exeter showed no difference so far between areas with and without compost application.

Tim has also experimented with pasture cropping alongside WildFarmed, this involved using a Moore Unidrill to direct drill a heritage wheat blend into a hard-grazed herbal ley. The aim was for the existing ley to provide ground cover and nitrogen-fixation. Tim described the first attempt at pasture cropping as a “disaster”, with chicory swamping the wheat and making harvest impossible. A second attempt meant tweaking the herbal ley mix to make it less competitive, grazing tight, sub-soiling and spring tine harrowing for seed/soil contact and then direct drilling. This appeared to have good establishment up until May, at which point Tim noticed that about two-thirds of the crop was Westerwolds grass. Again, harvest was abandoned and the field grazed instead to utilise the crop and keep organic matter in the field. In future, Tim plans on removing grass from the mix and replacing with a species that has more winter-kill such as sunflowers/millet/sorghum.

As Tim’s time at Erth Barton draws to a close, we would like to thank him for his work on Farm Net Zero and wish him all the best for his future endeavours.

Key takeaways:

  • Bringing pasture and livestock back onto the farm has helped to improve soil quality.
  • Fertility extraction should be balanced with fertility building. This can be done as part of a rotation.
  • Even when experiments do not go the way we first thought, we can still learn valuable lessons from them.

The Fellfoot Forward Project: A Case Study

In December 2021, five farmers from the Fellfoot Forward Landscape Partnership participated in a carbon footprinting project in association with the Farm Carbon Toolkit. Based in proximity to the North Pennines AONB these five upland businesses demonstrated how livestock farming can work in conjunction with the wider landscape to produce quality food whilst providing environmental services such as water and air quality alongside carbon capture and storage. 

A carbon footprint, or carbon balance, is the measure of the total emissions and total sequestration associated with a particular business or product. For this project, the whole farm was measured to include all of the enterprises included within a farming business. When we discuss ‘carbon’ we are referring to ‘CO2e’ or ‘carbon dioxide equivalent’ which is a measure of the three main greenhouse gases carbon dioxide, nitrous oxide and methane. Different greenhouse gases have different dynamics within the atmosphere, consequently having higher or lower warming potentials and thus potency as a contributor to climate change. Therefore, ‘carbon’ as a term encapsulates all three of these gases under one metric so we can compare items such as fuel alongside the biological systems seen in livestock like for like.   

To produce a carbon footprint the farmers were asked to collect a variety of data associated with their business, including items such as fuel and water usage, livestock numbers and quantity of materials used for activities like silage wrapping or maintenance. Alongside these figures, it was also important to record the ‘natural capital’ of each farm holding – the resources found in the farmed environment which are managed as part of the business but provide wider ecosystem services and value – such as areas of woodland, length of hedgerows, soil organic matter and specific habitats such as floristically enhanced margins or wetlands. When all of these details had been recorded, the data was entered into the Farm Carbon Calculator to produce a carbon footprint detailing the balance of emissions and sequestration found at each farming business. 

For the farms included in the project action plans were created to highlight where emission savings can be made or sequestration opportunities maximised. All of the farms within the project were found to be likely to be able to reach a Net Zero, if not already in this position. A large factor on many farms to reach this target is proper accounting of carbon held within the soil as organic matter. For the Fellfoot Farmers who are in majority grassland systems, livestock can be utilised as a tool to increase organic matter in soils – either through grazing systems and the capture of sunlight to be stored as carbon, or through the return of manure to pasture for nutrient cycling. To fully account for the potential sequestration of carbon through the building of organic matter in soils regular testing should be conducted to measure and monitor the levels found in soils. If, like on many farms there has been no prior soil organic matter testing the best advice would be to select three or four key fields within the farmed area which are representative of the systems within the business. For example, if the farm was in a grass-based system, a field which is usually cut for silage, one only grazed and a traditional low-input or hay meadow would demonstrate potential underlying trends in organic matter across the landscape. Equally, if there is a range of soil types or diversity of land use on a single farm it would be perhaps useful to test fields representative of these features to better understand trends and consequently the best management approach to conserve existing carbon and build stocks in the future. As ever, when testing soils aim to minimise external variation by ensuring consistency in the laboratory used and the time of year when sampling.   

The project with the Fellfoot Forward farmers demonstrated the variety of approaches to upland livestock farming, from the number or type of stock to the management required to protect and enhance vulnerable habitats within their farmed area. Some of the farms included in the project had areas of peatland within their management, using cattle or sheep to maintain and conserve the landscape in association with government or local schemes to the benefit of the wildlife and ecology found there. Peatlands are a vast store of carbon and consequently, the condition of this landscape could greatly impact upon the land managers responsible for its status. More information is required to fully understand the dynamics of peat and how farmers can measure and monitor this landscape for not only carbon footprinting processes but also for generations to come. 

Carbon footprinting is a process that can be repeated on an annual basis, used as a monitoring tool for both the emissions and sequestration of a farming business but also to understand changes in management approach. There is a general underlying correlation between high carbon and high cost on many farms, with items such as fertiliser and blended livestock feed being both expensive and also a comparatively larger contributor of emissions. Therefore, conducting a carbon footprint not only has benefits towards understanding the environmental impact of a business but also can be used as a tool for resource optimisation and economic efficiency. 

Key findings

  • Conduct organic matter testing to understand the current carbon held within soils. Aim to repeat this testing every 3-5 years to understand whether your soils are sequestering (increasing in organic matter) or emitting (decreasing in organic matter) carbon. 
  • Account for things you are already doing such as hedge or tree planting that are under existing or future schemes.
  • Accept that you may not have all the data, aim to create a baseline from which you can repeat the process in future years and account for more information with more experience, time or understanding.
  • Identify ‘hotspots’ where emissions are highest. Except for cropping or livestock, are there particular items or categories which contribute a larger proportion of emissions than others, is there potential for reduction in these areas?

Carbon Farmer of the Year Farm Walk at Lockerley Estate, Hampshire – May 2024

In May 2024, the Farm Carbon Toolkit were delighted to hold a farm walk at Lockerley Estate in Hampshire, home to one of the finalists from our 2023 competition. We would like to thank the Estate Manager Craig Livingstone and one of the owners Sarah Butler- Sloss for being so generous in hosting the farm walk.

Everyone who attended the farm walk heard from Craig and his team on how he has managed to make significant reductions in business greenhouse gas emissions, enhance the farmland biodiversity and enhance business performance.

Introduction

Craig Livingstone took on the role of farm manager at Lockerley Estate, owned by the Sainsbury family, 9 years ago with the challenge to improve biodiversity, sequester carbon, increase the health of the soil, and make a profit. To achieve this, a mission statement was devised with a list of objectives that really helps the whole estate team to work collaboratively to achieve the farm’s goals.

With just under 2,000 ha in Stockbridge, Hampshire, Craig farms Lockerley Estate and Preston Farms as one, which includes arable, grassland, woodland, a veg shed, and pockets of countryside stewardship schemes and SFI options. The farm is also part of a joint venture sheep and cattle enterprise, gaining benefits from grazing and muck which is integrated into the arable rotation. 

Over 9 years, Craig and his team have managed to vastly reduce emissions by transitioning to zero till and reducing artificial fertiliser and chemicals by broadening the rotation and integrating livestock. Specifically, Craig has saved 56,000 litres of red diesel annually and reduced pesticides and N-based fertilisers by 46% and 53% respectively. Soil organic matter has also increased by 1.1%.

Despite focusing on biodiversity, carbon and soils, Craig’s number one priority is profit – every hectare must pay for itself. Where he can, countryside stewardship schemes have been stacked with SFI options to increase profits. In some cases, the options available have encouraged Craig to adopt techniques that, for example, provide integrated pest management because the overall payment in combination with reduced pesticides is more than the potential loss in yield.

Currently, there has been a 17% change in land use, however the farm is still producing 9,000t food (approx. 4.5t/ha). So how has Craig managed to take the farm and reduce its emissions and increase soil organic matter?

Here are some of the highlights from the walk:

Arable

Using a broad and diverse rotation and choosing varieties that require fewer inputs, Craig has managed to halve the farm’s emissions due to vast reductions in fertiliser and pesticides. This in part has been achieved through implementing a mixture of winter and spring cropping interspersed with diverse mixes of cover and catch crops; legumes such as peas and beans; rotating grasses and legume fallow. The farm is also experimenting with clover understories and poly-cropping, prioritising diversity to build fertility and maintaining cover and living roots in the soil at all times.

The farm’s transition to no-till, aided by a zero-tillage seed drill, has also resulted in improved soil health and structure, increasing porosity and facilitating better water infiltration and enhanced soil biological activity through less disturbance. A multi-pronged approach to reducing fuels and fertiliser usage.

Encouraging diversity

As mentioned, the farm has taken advantage of environmental schemes such as winter bird feed (AB9), flower-rich margins and plots (AB8), and nectar flower mix (AB1) for multiple reasons. In short, to connect the woodland and encourage a host of wildlife, provide integrated pest management, and to make land more profitable.

Perhaps most interestingly, the team have implemented 6m assist strips of AB8 within a select few arable fields to encourage pollinators, beneficial insects, and predators. The initial cost of the seed is expensive; however, in this instance, the farm is not looking to reseed any time soon (especially within the duration of the agreement). That combined with savings on pesticides, they have found it far outweighs the cost of seed – it makes business sense. 

Craig has also looked critically at areas that are susceptible to weeds, difficult to graze, areas where the land lies wet, or where the shape of the field is awkward. Here, he has taken land out of production and implemented AB1 or other schemes to benefit wildlife and pocket.

Composting

A big project on the farm is taking cattle FYM and producing a superior product in solid compost and liquid extract using the Johnson-Su methodology. Agricultural soils tend to be bacterially dominated through repeated cultivations and chemical inputs but this process favours fungal communities which are excellent at cycling nutrients, disease suppression and soil aggregation. 

Good quality cattle muck is mixed with clover bales, straw, and woodchip, and through a series of steps breaks down into a fungally dominated compost. 

Once ready, a compost tea is created by placing a mesh bag full of compost into an IBC of water which is left to steep. This produces a highly nutritious and microbially active substrate which can easily be spread during drilling (rip and drip) and goes a lot further than the compost itself as well as reducing reliance on bagged fertiliser.

Veg Shed

Set up three years ago with a strong commitment to benefitting health, community, and the local environment. The veg shed is made up of 2 acres, 3 polytunnels, 40 laying hens and a fruit cage. The garden grows 50 different fruits and vegetables which it sells to local businesses on a wholesale basis but mostly through a local veg box delivery service.

Everything is grown from seed using heritage and heirloom varieties which have more diversity, and from testing, seem to have more nutritional value. They are also more resilient to a changing climate responding better to drought and high rainfall and requiring less inputs than other high yielding varieties.

The garden is designed as a polyculture and receives no artificial inputs, instead utilising compost from the farm and enlisting the help of dynamic accumulators to extract and release nutrients from the soil.

Wood pasture and Woodland

Linking SSSI woodland and calcareous grassland, the farm took advantage of the woodland pasture creation scheme and introduced longhorn cattle to graze instead of taking silage and hay. The aim is to create a large grazing area of species rich grassland and wood pasture that joins with 220ha of woodland improvement.

There is over 300ha of woodland at Lockerley Estate including a portion of semi-natural ancient woodland. The improved woodland is periodically thinned whilst retaining canopy cover to maintain diversity. Timber is harvested and removed with a percentage of profits returned to the estate.

The biggest outcome has been the flourishing biodiversity and wildlife. Diverse grassland is growing out from the hedges and wildflowers are starting to recover, blending into the woodland, and creating a mosaic landscape. Bird surveys see an increase in species year on year and botanical, butterfly and grasshopper surveys with fixed point photography are ongoing.

Hedgerows

Last but not least, Lockerley Estate takes great pride in its hedgerows, planting 12,000 hedgerow plants in the last year. Cutting regimes have also been lengthened to support all wildlife, from insects to birds to small mammals. This is made possible by replacing the hedge cutter with a saw blade to accommodate the thicker branches; the trimmings are then used for ramial woodchip in the composting process.

Summing up

Overall, it was a thoroughly enjoyable day and an interesting insight into how Craig and the team manage to maintain a balance between a thriving farm both in terms of biodiversity and bottom line productivity. Craig has demonstrated that economic resilience can go hand in hand with reduced inputs and tillage without compromising on food production. Entries to this year’s Carbon Farmer of the Year competition close on the 14th June, so  if you believe you are reducing on farm greenhouse gas emissions do enter our competition here

Carbon Farmer of the Year Farm Walk at Durie Farms – November 2023

The 21st November 2023 came in as a bright and sunny day, in stark contrast to the near constant rain which had fallen for the previous weeks.

The occasion was the farm walk for FCT’s Carbon Farmer of the Year Competition on the winner’s farm – Doug Christie of Durie Farms, Fife. Durie Farms is a mixed farm combining arable and cattle enterprises, organic and non-organic as well as woodland.

Liz Bowles (Left) CEO of Farm Carbon Toolkit welcoming people to the farm walk

Before we set out on the walk, Doug introduced his farm and explained some of the practices he has adopted which earned him the title of Carbon Farmer of the Year.

Fundamentals include the incorporation of conservation agriculture (minimum till cultivations and more complex arable rotations including peas and legumes within the rotation as standard) and the integration of extensively managed cattle within the whole farm. Central to this has been regular soil analysis with records going back to 2006. These records include soil organic matter which means that Doug is able to track soil carbon changes over time too. Unusually for the time, Doug also measured soil bulk density  which makes carbon stocks estimates more accurate. Alongside measuring soil carbon stocks, Doug also keeps enterprise fuel allocation records which has allowed him to have a much better understanding of hot spot areas. Through doing this he was able to identify the high fuel usage associated with housing cattle in the winter. This knowledge together with his adoption of holistic grazing practices has enabled him to keep cattle out longer,  with some groups of cattle e.g. in calf heifers now not being housed at all.

Our first stop on the farm walk was the large heap of brushwood next to the farm lane (a result of woodland management) and a question posed to the walkers as to how best to deal with this. Burning the pile would release a lot of carbon dioxide, but would that be less than chipping the pile and then burning it as a fuel? Or what about leaving it to break down naturally and possibly combine with farmyard manure and use as a soil amendment?  Now we are starting to look at these things through a number of lenses, these are the sort of questions farmers are increasingly grappling with.

The first field we entered was growing a cover crop, established in mid – late August after a cereal crop.

Doug Christie  (on the right, spade in hand) describing the cover crop

Doug now makes up his own cover crop mixes using farm saved seeds when possible. The cover crop had really motored on since early September and was providing pretty good canopy cover, in flower and up to waist height.  This cover crop will be holding nutrients in the soil, keeping living roots in place and improving soil structure through the varied rooting depths of the different plants in the cover crop.  Doug puts cover crops in place wherever possible and, for cereal harvesting, uses a stripper header leaving straw to rot down and provide food for earthworms. This was evident when inspecting a soil pit where the number of worms was high – worms everywhere. In fact this field which had been harvested with a stripper header, and had been undersown with a grass clover mix, with cattle having been mob grazed across it a few weeks earlier. The cattle had removed some of the straw and helped to break down the rest, and on the day of the farm walk it was clear that the grass clover sward was coming away nicely. Testament to the improving soil health at Durie Farms is the fact that Doug sold his subsoiler some years ago- surplus to requirements!

Doug shared with the group that he has not used insecticides since 2003 and is now working closely with the James Hutton Institute to carry out research on his farm. He has a fantastic site to investigate the impacts of this decision on insect life on the farm.

Arriving at the in calf heifers as we walked across the farm, it was clear they were wondering if it was time to make their move for the day. 

In calf heifers curious to know what we were talking about

Donald Christie, Doug’s son commented that since moving to holistic grazing and generally daily moves the cattle have become much more biddable, and in the move to outdoor wintering the challenge has been to make sure that this group do not carry too much weight as they approach calving. They receive no supplementary feeding when on grass.  One of the group commented that since adopting holistic grazing cattle health has improved and that the growth rate of outwintered animals surpassed that of housed cattle the following spring.

The group asked Doug what he is doing to reduce his reliance on artificial N fertilisers, one of the hot spots for arable farmers. Through improving soil health and bringing pulses and legumes into his cropping rotation Doug has reduced his reliance on granular urea by 30% since 2009. Yields have gone down but net margin is up. When choosing inputs such as fertiliser it is worth noting that different branded products, produced in different parts of the world, may have very different emissions factors. At Farm Carbon Toolkit, we offer Calculator users the ability to choose the product they have used so an accurate figure for emissions will be included.

The group also tackled the topic of cattle and methane, with an acknowledgement of how complex this topic is. The box below discusses the reasons for looking at a better mechanism for accounting for methane, one of the shortest lived greenhouse gases and one which is produced by ruminants as an intrinsic function of rumen function. 

What is becoming clearer is that how cattle are managed will have an impact on their overall impacts on our environment. Certainly Doug is minimising their negative impacts, through minimising their consumption of foods which could be eaten by humans directly, minimising their use of other sources of emissions such as fertiliser and fuel and making sure that their grazing activity has a positive impact on the soils they stand on and sequestering as much carbon as possible in their wake.

Accounting for methane: GWP* and GWP100
GWP (Global Warming Potential) is a measure of how much impact a gas will have on warming the atmosphere. The most common method to evaluate the effect of different greenhouse gases (GHGs) is by comparing them over a 100-year lifetime; this is known as GWP100. This is the internationally agreed metric chosen under the Paris Agreement and the primary tool for emission reduction targets globally. 

Using GWP, it’s possible to compare the impact of different GHGs by converting them to their carbon dioxide equivalent (CO2e) value. The latest research suggests that using GWP100, biogenic methane emissions are 27 times more powerful than CO2; and nitrous oxide (N2O) emissions are 273 times more powerful. However, unlike CO2 and N2O gases that last for hundreds of years in the atmosphere, methane only lasts for an average of 12 years after which most of it is broken down. This means that using GWP100, the impacts of methane could be considered overestimated in the long-term, and underestimated in the short term. 

In an aim to better account for methane, in 2016, a team of researchers proposed a new metric, known as GWP* that works over a 20 year period. Over a 20 year period, emitting a tonne of methane today has 80 times more temperature impact than carbon dioxide. However, the new metric is also designed to reflect the warming impact of ongoing emissions of methane in relation to the current levels of that gas in the atmosphere. The theory is that, over time, ongoing emissions are not adding warming to the atmosphere, but merely replacing old emissions that have degraded. Essentially, GWP* focuses on changes in emissions rather than absolute emissions. This accounting approach has been gathering support within UK agriculture sector, however it does also face some criticism (example).

As we turned for home, and the beckoning hot drinks and cakes, conversation turned to reducing the negative impacts of growing potatoes and the potential for woodland to sequester carbon into trees. On the topic of reducing the harms associated with growing potatoes there is a clear role for keeping living roots in the soil for as much of the year as possible, but to date no alternative has been found to the punishing soil management routine required to grow potatoes, although research is underway.

Liz explaining to the group how woodland is accounted for in the Farm Carbon Calculator

Doug has 50ha of woodland across the farm, with different areas having been in place from 10 -240 years. As his summary carbon footprint report shows, the woodland at Durie Farms alongside soil carbon sequestration offset the business GHG emissions last year. Of the total sequestration, woodland contributed around 50%. It is worth noting that the carbon sequestration associated with woodland depends on the growth rate of the tree. The Woodland Carbon Code has developed “look up tables” for this which the Farm Carbon Calculator  has incorporated into the sequestration area of the Calculator. For users, providing accurate information on the age of the trees as well as their varieties will enable a more accurate assessment of the scale of sequestration to be given. A rule of thumb is that most trees sequester only small amounts of carbon for the first decade or so of life. From the age of around 15 – 30 years carbon sequestration is at its maximum. After that age growth tends to slow down and with it carbon sequestration.

Doug is continually trying new ideas, with pasture cropping a new initiative he has ‘frustratingly’ tried this year. Doug’s long term membership of BASE UK  has supported him in his quest for adopting new and more sustainable farming practices. A quick look at the BASE UK website revealed a number  of fascinating events coming up in the next month including this one:

14/12/23 BASE-UK Member Nick Wall will present his review of the study tour recently taken by 15 members to visit Frederic Thomas and other BASE France members in November 2023 – it wasn’t all good food and drink – there was some learning involved! 

Back in the cattle yard (not in use yet) we finished with a round up of questions, answers and general discussion.

Thank you to our hosts, the Christie Family, for a memorable farm walk and great hospitality.

Farm walk with 2022 Soil Farmer of the Year Runner-up Andrew Rees

In the first week of August a range of farmers and industry professionals met at Moor Farm in south west Wales to hear the 2022 Runner-up to the Soil Farmer of the Year competition, Andrew Rees, explain how he has developed a dairy system with soil health at the centre. 

Moor farm is a 160 hectare grassland farm near Haverfordwest, which over the previous five years has been undergoing a holistic regeneration away from winter brassicas and a high input system to a fully rotational grazing system integrating diverse species-rich swards. Andrew has seen significant benefits to his business from this change of approach, including a reduction in fertiliser cost and usage alongside better herd health demonstrated by the vast reduction in veterinary fees.

Experimenting with different mixtures and management has led Andrew to create a system intended to provide year-round forage for his dairy herd. Moving away from pure perennial ryegrass leys has had its challenges, but Andrew explains

“Working to a 21 day grazing rotation is stressful, you can quickly run out of grass during adverse conditions, the aim of using herbal and diverse leys was to increase the resilience of the grazing platform. Now we have much more ahead of us and much more flexibility within the system where we aim for a 60 day rest period, but this can be up to 120 days in some cases”.

He adds,

“We started by sowing simple herbal ley mixtures, but as they were still managed like ryegrass we lost a lot of the diversity and therefore also potential yield. Now we have much longer rest periods between cutting or grazing to allow for regrowth and the leys are far more resilient.”

Fields are divided into 0.1 hectare blocks and animals are moved according to need. Andrew now has a keen eye for how much forage his grazing groups require despite the wide diversity of covers across the farm. When asked about his system Andrew states,

“We use a leader-follower approach whereby the R2 cattle (10-22 months old) follow the R1 heifers (3-10 months old), with 24 hours between the groups in each grazing cell. Having the smaller cattle grazing first means they have preferential grazing and we are not limiting their intake in any way, not forcing young animals to graze down also helps lower worm burdens. Older animals can then be pushed a bit harder and are able to deal with the more mature forage”

He further adds,

“Anything which isn’t grazed is hopefully trampled; that is when we know we have the stocking density and number of moves per day right – if the ley is starting to become a bit stemmy we move them more often, up to three times per day.”

This trampling action which Andrew integrates into his system has wider benefits for the soil in that it is better protected from environmental conditions and also now of higher quality with the constant organic additions from the leys above. Andrew fully promotes this system outlining to the group,

“Changing grassland management has given conditions for native seeds to germinate. We don’t want bare soils that cap and produce the conditions for weeds to appear. By keeping the surface covered with either growing plant matter or the trampled residue, we reduce our weed burden.”

Since the transition to more species-rich leys Andrew has found,

“The different rooting systems we have in the fields open the soil up and improve the structure, therefore we are removing the conditions in which weeds can become dominant.”

The R1 heifers from this spring moving onto a new block of grazing. Andrew uses a portable watering system to make sure troughs are easily accessible regardless of where the cattle are grazing.

The system Andrew has created focusses on a long rotational grazing platform for both the milking herd and young stock combined with deferred grazing to provide areas for out-wintering cattle. He explains,

“We used to have kale in the rotation to provide over-winter feed but were finding that there was far too much damage and soil wash. We now use a deferred grazing system to out-winter our R1 heifers which are between 8 to 10 months old. We position bales when the land is dry and travels well, ready to provide additional feed throughout the winter period.”

The condition of the soil and the health of the livestock are the key priorities when outwintering stock, to manage this Andrew explains,

“Heifers that are outwintered are scheduled to move every two days, but this can increase to three times daily to avoid soil damage if conditions become wet. This system works for us as our heifers are light and we still have the capacity to bring them in-house if the weather or soil requires it.”

Following these outwintering processes, fields are re-seeded, with Andrew tailoring off-the-shelf mixtures to suit his system,

“We have started reseeding with a half-rate Cotswold herbal ley mix, with half-rate Barenburg Barrmix (this was more because it’s what I had in the shed to give right balance of clovers and herbs) with additional annuals to provide a boost to performance in the first year whilst the other species establish”.

When establishing his leys, Andrew aims to use as simple and minimal cultivation system as possible, removing old or tired leys with low rate glyphosate buffered with humic and citric acid to lower the pH. He then drills the seed in two directions to increase the eventual cover with an application of seaweed to give a starter boost of nutrition.

Attendees to the farm walk gather in a spring established diverse ley which was previously used as deferred grazing this past winter. 

Andrew has, on average, reduced nitrogen usage by 140kg per hectare whilst still producing silage for the milking herd. He has recently started silaging the herbal leys which are highly diverse and contain species such as pea, barley, vetch, sunflowers, linseed, radish, chicory, plantain and a mixture of clovers. This will be analysed when the clamp is reopened and fed as part of the usual ration. In addition to regularly analysing silage, Andrew also frequently tissue tests his leys – results suggest the mineral content of his leys are double that found when they were in a perennial rye grass system. The species composition has a naturally far lower demand for nitrogen compared to perennial ryegrass and is much better at scavenging existing nutrients within the soil, further reducing the need for artificial inputs.

Andrew uses slurry in combination with a Tow and Fert system to help maintain fertility and production across the farm. Fields destined for silage are given slurry before and after the 1st cut with a 25kg sprinkle of N prior to cutting. The Tow and Fert is used to top up fine lime, phosphate and humates alongside some foliar potassium. Andrew samples a fifth of the farm every year, with the whole farm last sampled in 2018 – having this up to date data allows him to understand where his nutrients are most required and move away from broadacre applications. Fine lime is regularly used across the farm with Andrew detailing, “Applying fine lime helps increase the free exchangeable calcium in the system, we are aiming to have calcium at luxury levels which will take time but will help with the longevity and palatability of the tall covers.”

As a dairy farmer, herd health is a main priority for Andrew. Through implementing changes to grazing species composition and management, alongside reducing the nitrogen use across the farm, livestock performance has seen vast improvements. The dairy herd are also grazed on diverse summer cover crops, being turned out for a few hours after milking.

Andrew explains this strategy,

“Having the cows grazing across the diverse leys has improved butter fats and allowed us to stretch out the grazing season where historically we may have run out of grass. This means that the herd is currently balanced between herbal leys, traditional grass pasture and silage in the yard when they come in to be milked. The additional grass means we only need to supplement feed them around 4kg of cake per day, massively reducing costs.”

The cows are now found to be far more content, with lower nitrogen covers thought to lower the free nitrates in their system, reflected in the results of the milk testing. This contentment has also improved fertility and the health of the dairy herd. Empty rates have decreased from 10.5% in 2019 to 5.5% in 2021 with mastitis per 100 cows also reducing from 19.7 in 2019 to 3.5 in 2021.

The milking herd grazing following afternoon milking, the whole herd is mob grazing this 0.1 hectare paddock full of highly diverse species.

The increased fertility in the herd has also allowed Andrew to move his spring calving system later so they can calve to match the grass growth, reducing the housing requirement as calves are weaned on grass with outside grazing access from 4 weeks of age. Worm burden has also drastically reduced and consequently, so has the requirement for anthelmintic products. Faecal egg counts are conducted to see if any wormers are required, however Andrew has found that due to the long-grass grazing system with animals biting higher up the plant in combination with chicory rich pastures, very little, if any, are required. 

When asked about how he would advise others beginning along the herbal or diverse ley journey Andrew has these words of wisdom,

“Start by drilling the leys in the spring as this gives a much better chance for establishment whilst you are experimenting with your system. If you are going in later when the conditions could be dryer or colder it might be tough on the clover to get up and away.”

At Moor Farm, the leys are highly diverse and full of many different species. Andrew’s thinking behind this is,

“When you establish herbal leys you can often see a drop in yield compared to a perennial ryegrass whilst they establish, therefore we also drill in summer annual species to help build the quantity of forage available to graze. If we are establishing a ley in the spring, we would expect to be able to graze it that autumn. However, this would be a lighter graze than in the second year and not as tight, just to make sure we don’t stress the plants too much”. 

The remaining cover approximately 1 week following grazing ready to be re-drilled compared to one of Andrew’s diverse leys which has recovered following previous grazing. 

The next challenges for Andrew focus further around nitrogen reduction, as he discussed with the group,

“The aim would be to be using zero chemical nitrogen whilst managing to maintain our current production. I want to be able to leave the land in a better condition than when we started whilst also being financially profitable.”

During the Soil Farmer of the Year competition, the judges found Andrew’s approach highly innovative, understanding how to maximise the health of the soil to produce high quality, mineral rich forage for his cattle using less inputs, but instead through his grazing and nutrient management system. The benefits Andrew has observed upon the health, welfare and productivity of his cattle through diversifying the leys has been highly successful – also giving him additional flexibility in other areas of the farming business now he is secure in the growth of forage on the farm, developed through increasing the resilience of his system. 

Ourselves at FCT would like to thank Andrew, his family and his team at Moor Farm for such an excellent tour, providing insight in how the system works and inspiration of what is possible for dairy grazing systems. The Soil Farmer of the Year competition is run by FCT in association with Innovation for Agriculture and this year has again been kindly sponsored by Cotswold Seeds and Hutchinsons. If you would like to find out more about the Soil Farmer of the Year competition please keep an eye on our website for updates on the other farm walks in October 2022 and the opening of the 2023 competition.