Category: Insights

Five farms in Cornwall on a journey towards Net Zero

Posted on January 18, 2024 by - Case Studies, Farm Net Zero, Insights

We’re excited to share a series of five new videos that showcase some of the farms in Cornwall that are part of the Farm Net Zero project.

Each video shares a different farm’s journey as it works to improve the environment, produce nutritious food, while also responding to climate risks, such as flooding. There is a specific focus in these videos on how the farms are engaging within their local communities, to help tackle these issues. The Farm Net Zero project includes practical advice for farmers on how to reduce greenhouse gas emissions, showcases innovation, provides robust science through soil testing and carbon footprinting, and inspires other farmers to tell their stories to consumers on the steps that they are taking to address climate change and protect soil health.

The full-length video below includes all of the following five stories. If you prefer to view each story separately, please simply click on each of the links here:

The complexities of calculating livestock emissions

Posted on January 11, 2024 by - Calculator, Insights

What do we mean by livestock emissions?

Emissions from livestock cover two broad categories:

  • Enteric methane emissions (this is the methane produced by the animals digestion)
  • Greenhouse gas emissions from the manure and slurry produced by the animals.

When you enter a group of animals in the Farm Carbon Calculator e.g. 100 dairy cows, the Calculator will consider both enteric methane emissions and the nitrous oxide, ammonia and methane emissions associated with the manure or slurry those 100 dairy cows produce over the course of 1 year.

It is really important to enter the average number of animals in a category over the course of the year rather than the total number. For example, if you have 100 dairy calves on farm for only 6 months of the year, you should enter 50 dairy calves. Otherwise the Calculator will have to assume that all 100 calves are on farm for all 365 days of the year, which would overestimate the enteric methane production and the amount of manure produced.

Why do the emissions associated with livestock vary?

In the Farm Carbon Calculator, we ask users to tell us the number of livestock in a range of different livestock categories. The emissions produced by animals will vary based on:

  • Number of livestock (more animals means more emissions)
  • Liveweight of animals (larger animals tend to produce more manure)
  • Type of livestock (ruminants produce enteric methane, monogastrics don’t. Each type of animal has its own “rate of excretion” and different animals’ manures produce methane at different rates)
  • Pregnancy and lactation (pregnant or lactating cattle produce more enteric methane for their size)
  • Manure or slurry storage (rates of methane and nitrous oxide, emitted indirectly through leaching and ammonia volatilisation, vary depending on how the manure is stored and for how long)
  • Where manure/ slurry is spread (if manure is spread, the type of land it is spread on will affect the rate of indirect nitrous oxide emissions through leaching).

What about slurry covers, storage bags, slurry bugs etc… ?

We are actively working on incorporating a lot more options into the Farm Carbon Calculator to allow users to give more detail on their manure management practices. We plan to include options in 2024 for sending manure and slurry to anaerobic digestion, adding detail on slurry pit coverage, storage timing, and different application or incorporation methods for slurry (e.g. trailing shoe versus splash plate).

We are also researching the possibility of including slurry bugs (bacteria that inhibit greenhouse gas production from slurry stores) and chemical nitrous oxide inhibitors (that reduce the emission of greenhouse gases when the slurry is applied to the soil) as options so that users can show the benefits of these in reducing their slurry emissions. Similarly, we would like to be able to include methane inhibitors that can help to reduce enteric methane emissions for livestock.. To date though, the quality of independent scientific evidence for these management practices is very variable and different products show variable results depending on the farm environment, so it is harder for us to give robust estimates of the effect they will have on a farm’s emissions.

The importance of managing manure on-farm 

Posted on January 11, 2024 by - Insights

Written by Becky Willson, Business Development & Technical Director.

Manure is a fantastic on-farm resource. This is because it can deliver a source of nutrients that can be used to grow crops, as well as enhancing soil biological activity, feeding the soil microbes and helping provide a steady supply of organic matter. This can ensure that soils are in the best condition structurally, chemically and biologically. Manure is one of the most important resources that is produced on-farm, and should be valued rather than seen as a waste product. 

A key way to be able to reduce reliance on fertilisers is to develop efficient and effective strategies for managing nutrients and manures on-farm. 

Nutrient management planning

Managing nutrients in a systematic way through planning is a vital aspect of sustainable farming. It is a ‘win-win’ practice which generates advantages across economic and environmental parameters, and allows for the creation of a sustainable agricultural system which is resilient to climatic and economic change. 

Nutrient management planning facilitates optimal use of nutrients from all available sources. Matching inputs of nutrients (from fertilisers and organic manures) to the demand from the crop will allow for an optimal yield, minimise the use of nutrients (which saves costs) and minimises the risk of losses to the environment from nutrients.  

Slurries and solid manures are valuable fertilisers but may also be potential sources of pollution. Within increasing economic and environmental pressures on farm businesses, it makes sense to exploit the fertiliser value of manures while taking action to prevent pollution. 

Most farm assurance schemes require a manure management plan to be completed as part of the certification process. However even without the compulsion of a scheme, having a plan which marks out any environmental features, watercourses, sloping fields which may cause run off and any areas will be a useful resource to consult before applying manures.  

The need for effective manure management

The most effective way of dealing with livestock manures is to apply them at appropriate rates to agricultural land for the benefits of soil and crops. Getting manure management right allows for sustainable use of resources which provides economic savings and reduces the amount of artificial fertiliser that is required. Manures, when stored and applied correctly have fantastic benefits in building resilience within your farming system, cutting costs and lowering your carbon footprint, however if they are applied in too high a quantity or at the wrong time of year then they are an environmental risk. So it is the job of farmers to maximise the benefits that can arise and minimise the risks.

Nutrient management planning to mitigate greenhouse gas emissions

Nitrogen emissions to the air from farms include greenhouse gases, the most potent of which is nitrous oxide. Nitrous oxide is one of the biggest contributions that agriculture makes to climate change. Soil nitrous oxide emissions originate from three sources, soil microorganism activity (55%), organic manure applications (18%) and Nitrogen fertiliser applications, (27%). As such, careful management that maximises the efficiency of any fertiliser applied, takes account soil and climate conditions, and uses the nutrients within manures for crop growth will help to reduce the amount of nitrous oxide lost. 

Nutrient and manure management planning will also help reduce ammonia emissions. While ammonia isn’t a greenhouse gas, it negatively impacts air quality and human health. The amount of ammonia which is lost depends on a variety of factors including manure type, the method and timing of applications, soil pH, the weather conditions at spreading, the soil moisture content and how the manure is stored. As such there are a variety of mitigation options available that are made easy by planning how manure is managed to reduce these risks. 

Soil Testing

Although not always considered as linked to nutrient management planning, monitoring and controlling the pH of soils on-farm is the first step toward good nutrient management. If soil pH is not correct then any nutrients that are applied through fertiliser or manure applications will not be available to the crop and may be lost from the soil incurring costs, reduced yields and pollution issues. 

Effective use of manures – Storage

Having sufficient slurry or manure storage means that effective nutrient management planning is much easier. With sufficient storage capacity, slurries and manures can be applied at the optimal time for plant growth and crop uptake, as well as being applied when the soil and field conditions are right and damage (including compaction and run off) is minimised.  However for some farmers who don’t have enough storage, slurry has to be spread in less than ideal conditions, when there is little crop growth and nutrient uptake. It is in these situations where environmental losses can be the highest. 

Thankfully there are ways that storage can be optimised. This can include minimising the amount of rainfall that is able to enter the store. Rainfall can dilute the nutrient content of the slurry but also costs more in manure application – more water is held within the slurry leading to a higher volume to be spread. Mending guttering, diverting clean water away from stores and covering yards to minimise the amount of water that is entering the store are all low cost ways to help maintain the nutritional value of the manure and also reduce costs. Covering stores is also an option and there are various cover options that are available depending on the store type and design. Floating covers will also reduce the amount of ammonia which is released into the atmosphere which has air quality benefits. 

With solid manure it is important to consider the siting of field heaps and managing the heap to ensure that Nitrate leaching is minimised. Composting of FYM will provide a more stable and uniform material which will have benefits for soil biology, but will not provide such a high readily available Nitrogen source as fresh manure. 

Effective use of manures – Application 

Ensuring that manures are applied at the right rate and the right time is the most important step to reducing environmental risk and improving economic performance of the farm.  The method of application can affect the amount of nitrogen that is available to the crop. Although the total nitrogen content within the manure cannot be altered by the method of application, the proportion of the nitrogen that is available to the growing crops is improved by using low trajectory machinery.

Spreader technology has developed over recent years so that now there are numerous options available for spreading slurry (where losses are potentially higher). Broadcast spreaders will waste nutrients, but this can be minimised by using injection or band spreaders which put the slurry directly on the soil surface or into a narrow slot. For solid manures, the evenness of spreading is far improved by using a rear discharge spreader. If manure or slurry is to be incorporated, ensuring that it is done quickly after application and not just left on the surface where the nutrients may well be lost is important.

Optimising the use of manures and slurries on-farm will provide benefits through improving profitability, resilience and soil health. For more information on manures and nutrient management planning please visit the FCT toolkit pages to access a range of resources.  

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

Posted on January 4, 2024 by - Case Studies, Insights, Soil Farmer of the Year

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

Posted on December 14, 2023 by - Case Studies, Farm Net Zero, Insights

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.

How do we measure peatland?

Posted on December 7, 2023 by - Insights, News

Understanding the carbon dynamics of peatland is a complicated process that is ever-changing for land managers and farmers. Historically, peat soils and habitats have been understood as a carbon store, with peat itself being of extremely high carbon content. However, in the process of carbon footprinting it is required to understand all greenhouse gases associated with peatland (carbon dioxide, methane and nitrous oxide) and the additional storage of carbon into these soils, a process known as sequestration. 

Sequestration is the process of capturing carbon from the air and storing it within the land, through the process of photosynthesis. Within peatland soils there are additional layers of complexity when thinking of carbon storage. The waterlogged conditions of peat soils allow decomposing plants to accumulate, storing the carbon in the form of peat; this means that not only is carbon captured and stored via photosynthesis, but that there are direct carbon additions from the plant structures themselves. 

Consequently, measuring peatland within the Farm Carbon Calculator or any carbon calculator can be complex – knowledge in the scientific community alongside methods of accounting are rapidly developing. However, the following methods can be used:

  • Direct Measurement: soil sampling the peatland soil to understand the carbon content (Soil Organic Matter or Soil Organic Carbon testing) provides a figure of the carbon stock within an area. Carbon stock is the quantity of soil contained within a soil at the time of measurement and is calculated in combination with a Bulk Density sample. To understand if your peatland is sequestering carbon (capturing more, additional carbon) this sampling needs to be repeated to understand whether the figure measured in the first instance is increasing or decreasing. Soil sampling can be conducted annually, but there is often concern around carbon flux so the Farm Carbon Toolkit would usually recommend sampling every 3-5 years. More can be found out about how to sample soil in our free online guide to monitoring soil carbon on the FCT website here.
  • Modelled Measurement: if however direct measurement is unsuitable or you would like a faster indication of the carbon dynamics of your peatland soil you can use modelled figures embedded within the Farm Carbon Calculator. Using data from the Peatland Carbon Code 2.0 there is the ability to account for peatland areas of the landscape through selecting the type of peat you have and the area (hectares). The calculator will then provide a modelled suggestion of the likely dynamics of the different greenhouse gases associated with the different peat classifications. 

The Fellfoot Forward Project: A Case Study

Posted on December 7, 2023 by - Case Studies, Insights

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

Posted on June 6, 2024 by - Carbon Farmer of the Year, Case Studies, Insights

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

Posted on December 4, 2023 by - Carbon Farmer of the Year, Case Studies, Insights

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.

Risky Crops

Posted on September 15, 2023 by - Insights

Certain crops (potatoes, sugar beet, maize, field vegetables) within a wider arable rotation pose increased risk of soil loss or degradation. Often described as ‘risky’ these crops may require additional management to ensure that field conditions are favourable and that there is no long-term disruption to soil functionality or structure. 

Aside from the impact upon soil, ‘risky crops’ are often those which have a potentially higher financial burden through the obstacles of production. Rising input costs, labour shortages and ever increasing inflation presents additional challenges to high-risk, high-reward crops. These two elements (soil management and economics) are additionally impacted through the changing climate with record temperatures and rainfall events.

Root crops, maize and field vegetables are often at high risk for soil degradation. The likely drastic requirements for cultivation during seedbed preparation is a vast source of emissions through direct carbon losses from soil alongside the burning of fossil fuels from machinery. Cultivating soils and the subsequent disturbance allows for greater oxidation of the soil profile, therefore promoting the fast metabolism of aerobic species of microorganisms which utilise the ‘active’ pool of soil organic matter for respiration, consequently releasing CO2 as a by-product. Furthermore, cultivation of soil which reduces the stability of the soil structure can also be at risk of direct losses of carbon bound to soil aggregates through processes such as erosion either through wind-blow, run-off or direct soil loss.  Therefore, depending upon a number of factors such as previous cropping, soil type, intensity of cultivation and moisture content, cultivated soil will lose soil organic matter at differing rates. Where land is under continual cultivation, as is much of UK arable land, reducing the frequency, depth and intensity of cultivations will reduce this soil carbon loss alongside providing alternative carbon sources as feedstock for microorganisms when cultivation is required. 

Changing the crop establishment system to reduce the frequency and intensity of cultivations will provide an immediate reduction in farm greenhouse gas emissions. Increasing organic carbon within the soil requires the building of soil organic matter through methods such as diversifying crop rotation, reducing tillage (frequency and depth) and utilising cover cropping to maintain a living root. 

Long-term rotational planning can increase the resilience of soil, using previous and subsequent cropping and management choices to minimise the impact of risky crops. To reduce the ‘risk’ of risky crops soil protection is central. Ensuring that soils are covered throughout the rotation and contain a living root for as high proportion as possible helps guard the soil from physical degradation from climatic events. Therefore, consider growing a cover crop before spring planting to scavenge nutrients over the winter period and condition soils, alongside aiming to re-plant a cover as soon as the risky crop is harvested to avoid long over-winter periods of soil erosion. Maximising the inherent soil structure and functionality throughout the rotation creates a more resilient baseline where the stresses of high cultivation, inputs and exposure to the elements occurs in high risk crops.

In grassland systems herbal leys, diverse swards and a rotational or mob grazing platform provides an excellent starting point for soils before a high-risk crop or to repair potential damage. Likewise a diverse arable rotation which incorporates cover, inter, companion or catch-cropping to protect the soil surface and provide additional rooting architecture will be a huge benefit; tired land, used to high input use, heavy cultivation and monoculture systems will be less resilient to stress (environmental, mechanical etc) than a healthy vibrant soil. 

A healthy soil is likely to provide better economic returns – with processes such as fertility, water infiltration, gas exchange, rooting capacity and nutrient availability all benefited by a well structured, high quality soil. Soil organic matter can often indicate the health of a functional mineral soil, with the higher the percentage content normally suggesting the best quality. Understanding how soil organic matter can be lost during high risk cropping processes (discussed earlier) can help to mitigate and safeguard it within the rotation. Losing soil organic matter continuously depletes the soil fertility and consequently the likely economic potential of that land. 

This blog was written by Emma Adams, one of our Farm Carbon and Soils Advisors, to read about our team head here.

More information:

For further information on species selection of cover crops and the results of the Farm Net Zero trails please see the resources below: