Category: Insights

How do emissions of biomass crops compare to arable & livestock farming?

There is a growing interest in biomass crop cultivation in the UK to provide materials for biobased products and to offer environmental protection benefits. Biobased materials offer an alternative to single use plastics, construction materials derived from fossil fuels and can replace peat with home grown wood fibre from fast growing perennial crops. In collaboration with AFBICrops for EnergyCalvium, and supported by funding from the Centre for High Carbon Capture Cropping (CHCx3), we investigated the greenhouse gas (GHG) emissions associated with growing various biomass crops in the UK compared with arable and livestock farming.

The emissions calculations will be provided on the Envirocrops platform, whose development has been funded by DESNZ, to aid farmers in decision-making when considering switching part of their land into biomass crop cultivation.

Willow stands as part of a short rotation coppice regime. Image credit: Biomass Connect Website https://www.biomassconnect.org/biomass-crops/willow/.

What we did 

We provided two arable and six livestock farming scenarios to compare with the cultivation of six different biomass crops and modelled the associated emissions using the farm carbon calculator (see Table 1). As some of the biomass crops have a long lifespan (10 – 25 years) with the potential for multiple harvests from one planting, the emissions for each farming scenario were modelled over a 20 year period. 

The biomass crops included in the project were short rotation coppice (SRC) willow, SRC poplar, miscanthus, switchgrass, reed canary grass and hemp. As hemp is an annual crop, it was swapped in for a crop in the arable 3 or 5-year baseline rotations. For the other biomass crops, two scenarios were modelled, either conversion from arable land or conversion from grassland, which differed in their field preparation operations and herbicide application, to provide the comparison to the arable or livestock grazing scenarios respectively.

Only associated emissions from the different farming practices were modelled but no potential carbon sequestration due to the high level of uncertainty and lack of current available research (particularly with biomass crops grown in the UK). Additionally, any emissions or sequestration from carbon stock changes in soils were not modelled, as this would vary largely depending on a variety of factors (e.g. location, soil type, season). Emissions were modelled to farm gate and do not include the downstream processing of crops. To see a more detailed outline of the data that went into the GHG calculations, visit our assumptions document here.

Table 1. The farming scenarios and their modelled emissions.

Scenario Emissions taken into account
Arable
3-year baseline rotation Rotation: Winter Wheat, Spring Barley, OSR
  • Crop residues left in the field
  • Fertilisers
  • Sprays and associated water usage
  • Red diesel usage from field operations
5-year baseline rotation Rotation: Winter Wheat, Spring Barley, OSR, Field Beans, Winter Wheat
  • Crop residues left in the field
  • Fertilisers
  • Sprays and associated water usage
  • Red diesel usage from field operations
Livestock
No input grazing cattle
  • Number of beef livestock (1.2 head/ha or GLU 0.9/ha)
  • Red diesel use
Low-input grazing cattle
  • Number of beef livestock (1.2 head/ha or GLU 0.9/ha)
  • Red diesel use
  • Fertiliser inputs (low)
High-input grazing cattle
  • Number of beef livestock (1.6 head/ha or GLU 1.2/ha)
  • Red diesel use
  • Fertiliser inputs (high)
High-input silage cattle
  • Number of beef livestock (2 head/ha or GLU 1.5/ha)
  • Red diesel use
  • Fertiliser inputs (high)
  • Silage crop residues
No input grazing sheep
  • Number of ewe livestock (11.25 head/ha or GLU 0.9/ha)
  • Red diesel use
Low-input grazing sheep
  • Number of ewe livestock (11.25 head/ha or GLU 0.9/ha)
  • Red diesel use
  • Fertiliser inputs (low)
Biomass crops
Hemp (conversion from Arable land) Swapped in for OSR in 3 and 5-year arable rotations
  • Crop residues left in the field
  • Fertilisers
  • Sprays and associated water usage
  • Red diesel usage from field operations
Miscanthus
Switchgrass
Reed Canary Grass
SRC Willow
SRC Poplar (conversion from arable and grassland)
  • Crop residues left in the field
  • Herbicides (field preparation and site restoration)
  • Red diesel usage from field operations

What we found 

As biomass crops can be planted once, harvested repeatedly and require little to no fertiliser inputs over the 20-year period, the emissions associated with cultivating biomass crops are considerably lower than the arable and livestock farming scenarios. 

Arable comparisons

The biggest contributor to the arable scenario emissions is from fertilisers (see Figure 1). Swapping hemp into the rotations decreases emissions by an average of 9.2% when compared to the average of the 3 and 5-year baseline rotations. 

For the perennial biomass crops, there is an average 95.5% decrease in tonnes of CO2e per hectare per 20-year period compared to the average of the arable baselines. This is largely because the perennial biomass crops do not require fertilisers, the application of sprays and fertilisers is often not possible once the crops are established due to their size. However, It is worth noting that soil testing and site choice are essential to help establish any nutrient requirements prior to biomass planting, which has not been included here due to its varying nature.

Additionally, because the rootstock of the perennial biomass crops remains viable for many years (excluding hemp), emissions associated with biomass crop residues are lower.

Figure 1. Total tonnes of CO2 equivalent per hectare per 20-year period (number above bar) for each arable farming scenario. Colours represent the emissions categories.

Livestock comparisons

Livestock comprise the largest proportion of emissions in the grassland grazing scenarios (see Figure 2), which is associated with enteric methane production and manure emissions. There is a potential average 97.6% reduction in emissions when switching to biomass crop production (per hectare, per 20-year period). 

Figure 2. Total tonnes of CO2 equivalent per hectare per 20-year period (number above bar) for the livestock scenarios. Colours represent the emissions categories.

Summary

From these example farming scenarios we can see that the emissions associated with cultivating biomass crops are substantially lower than arable and livestock farming. An increase in biomass cropping in the UK and Ireland has the potential to aid in the transition towards net zero goals, along with diversifying farming portfolios and income streams. Biomass crops can often grow on marginal land that may otherwise be unproductive. They can also be incorporated into food production systems, for example, SRC and short rotation forestry (SRF) tree crops can be planted as agroforestry silvopasture or silvoarable systems, to offer increased biodiversity in farming systems. As part of this project we were able to research and include additional biomass crop emissions factors in the Farm Carbon Calculator, contributing to our project aims on the CHCx3 project.

Soil Farmers: Leaders in Soil Management

Written by Jonathan Smith, Impact Manager, Farm Carbon Toolkit

For the last 10 years, Farm Carbon Toolkit has hosted the Soil Farmer of the Year (SFOTY) competition, seeking out the farmers and growers across the UK who are doing the best job at improving their soils and underpinning their businesses with healthy soil management. The 2025 competition is open now and you can enter here, as well as see details of our past winners. The competition runs in partnership with Innovation for Agriculture and is supported by Hutchinsons and Cotswold Seeds.

Over the years we’ve had many inspiring finalists, so we thought we’d share information on some of the winners, what they’re doing on soil management, and some top tips.

Growing soil biology

In 2018, SFOTY winner Simon Cowell, an arable farmer from Essex delves deep into soil biology to create the conditions for his crops to thrive. He makes his own compost and applies it at 2-4 tonnes/acre, more as an inoculant than as a fertiliser, as Simon explains:

It’s not being used as a fertiliser source or for organic matter, it’s purely an inoculation for the soil biology and a home to grow biology that will benefit the soil. Within a few weeks you can see the difference where it has been applied

Through a mixture of crop rotation, on-farm trials and compost, the use of applied Nitrogen has decreased dramatically and the use of agrochemicals. Noticing that the plants nearer the hedge look healthier, Simon comments:

My aim is to get the biology and fungal network to transfer all those benefits throughout the fields, although it’s going to be a slow process.

Farmers should be beekeepers

Over in Oxfordshire, another arable farmer was the 2019 winner. Julian Gold grows a range of crops on 800 ha, with a small flock of sheep to manage the green manures. He’s over 10 years into his journey of minimising tillage and covering the soil as much as possible. He’s tuned in to his soils and how they’re working now:

If you know your soil and are on the right trajectory, you don’t need to do soil testing. I can see the straw disappearing and see worm middens, I know it’s healthy and doing what it should be, but it can take time.

Trials with Universities and Research Institutes has been common on the farm over many years, and has looked at greenhouse gas emissions, soil health and biodiversity on the farm. Julian advocates that all farmers should be beekeepers:

…….as with all things its about a change of mindset. This is true of fertiliser use, crop protection and carbon farming

Using electric fences instead of fertiliser

In 2022, Herefordshire farmer Billy Lewis demonstrated how his mixed farm had turned around and really improved its soil massively. A combination of direct drilling, applying compost, mob grazing, reduced inputs and introducing legumes has transformed the soil health, productivity and profitability.

On the new grazing system, Billy comments:

Since beginning our rotational grazing system we no longer apply fertiliser to our permanent pasture. You will grow ten times more grass with an electric fence than you will with a bag of fertiliser.

Fertiliser use has reduced by 50% over 3 years, with an aim to eliminate it in the future

Noting that arable crops have become much more profitable now, and the livestock more relaxed and healthy, Billy believes this is down to both a reduction in inputs and an improvement in soil biology.

When we dig up any legume species, be it in a herbal ley, cover crop or in the clover living mulch, we’re seeing plenty of nodules forming and more importantly we are noticing that they are active due to the dark purple colour when they are sliced open.

Becky Willson at FCT’s Field Day in 2024, running a session on soil health at Billy Lewis’s farm

12 million worms per hectare

Arable farming can face greater challenges in rebuilding soil health and carbon. 2021 winner Tom Sewell is farming over 1500 acres in Kent with his wife Sarah. The farm is both at a serious scale but also working across a range of soil types. Minimum cultivation and direct drilling have been used for some time on this farm and Tom was an early adopter.

Through a combination of providing minimum disturbance, and adding organic matter – through straw, cover crops and compost, the organic matter has gone up worm counts are very healthy. Tom reckons there are 12 million worms per hectare!

A ‘simple system’ that maximises soil health has allowed them to reduce fertiliser use by 10% per year, yet maintain yields and improve soil health continuously. Tom says:

I just want to improve the soil, I use compost and feed the worms, they’ll do the rest.

Using all the tools

Over at Overbury Farms in Gloucestershire, 2020 winner Jake Freestone farms over 1500 hectares with a diverse arable rotation, plus 1,000 sheep across a wide range of soil types. Jake is using fungal-rich seed dressings to improve germination, soil biology and reduce costs. 

Nitrogen fertiliser is being reduced, other inputs reduced, cover crops experimented with extensively and sheep being a key part of the rotation. “

Jake comments:

Ultimately we are trying to use all the tools that we have to improve soil organic matter, water infiltration and wider water management, soil structure and soil biology to achieve the long term goal of improving our resilience both for our crops, our business and our soil.

A 10-year transformation

Back to mixed farms and in 2023 winner Stuart Johnson in Northumberland demonstrated how 10 years of work has transformed his farm, primarily by reducing inputs, improving soil health and livestock productivity. Moving to a strip-tillage system and mob grazing platform has provided financial success alongside a more resilient business. 

Stuart has now eliminated fertiliser on his grassland and fungicides in the arable crops, instead utilising an integrated system with the livestock and compost teas to grow what is needed on the farm. The farm is currently in a seven-year rotation of a five-year legume/herb mix followed by a two-year arable break with full grass grazing for the sheep and cattle meaning that there is no need to buy in additional supplementary feed over the summer months.

Herbal leys and vegetables

Bringing us right up to date, 2024 winners Tracey Russell and David Neman at Bucksum Farm in Buckinghamshire show in this video how herbal leys and vegetables sold directly is working successfully.

Creating their own compost, using extensive herbal leys (grazed by sheep), they also incorporate living mulches amongst the vegetable row crops. Incorporating top fruit and chickens too, the farm is an exemplar of how to grow fruit and veg in a sustainable rotation whilst improving soil health.

Learn even more!

We also have amazing 2nd and 3rd place Soil Farmers from each year, and you can read more about them here.

Don’t forget, if you think your farming practices are worthy of being entered in the competition, please do consider entering the 2025 Soil Farmer of the Year competition. It’s free – what have you got to lose?

A day in the life of… Grace Wardell, Calculator Development Officer

I’m Grace, one of FCT’s Calculator Development Officers. If you haven’t heard of FCT or our Farm Carbon Calculator, that job title probably means very little to you! So, let me explain what I do on a day to day basis to help maintain running one of the UK’s top 3 farm carbon calculators.

The Farm Carbon Calculator is just one branch of FCT’s work and is a tool within our online toolkit. Working within our Calculator team, my role is to ensure the Farm Carbon Calculator is based on rigorous science, remains up-to-date with standards and guidance, and is free of bugs that can sometimes appear when running a software.

To achieve these aims, I am regularly undertaking research, particularly if someone has requested an item on the Calculator, like a specific fertiliser or crop. I will find associated emissions factors, consult with experts in the field, alongside standards and guidance to ensure we are employing the recommended calculations.

Each year we undertake two major updates, one in April where we assess and update all emissions factors and one in October where we also look to improve the functionality of the Calculator. These are busy times for our team, where we work through and update thousands of line items on the Calculator to ensure we remain up-to-date with the latest science and data that’s available. All the while, I work alongside Lizzy Parker (Calculator Manager), James Pitman (Calculator Development Officer) and our software developers to keep the website running smoothly. 


Aside from my core work on the Calculator, one of the exciting things about working for FCT is the breadth of interesting projects we are involved in. I have undertaken farm modelling work for a few different projects looking to model the transition to more regenerative practices and the impacts that may have on greenhouse gas emissions. I regularly go to farming conferences to hear firsthand the issues that farmers are facing and can offer free advice on carbon footprinting their farm. I get to brush up on my science communication skills when posting blogs on our website on hot topics. I also get to enjoy our in person events such as our Annual Field Day, Soil Farmer of the Year and Carbon Farmer of the Year events, where we champion pioneers in sustainable farming.

Since we all work remotely and are spread far and wide across the UK, it is these in-person events and our Away Days that remind me how lucky I am to work with such passionate people who care immensely about our farmers, our environment and our food production systems.

A day in the life of… Calum Adams, Calculator Data Assistant

I’m Calum, the Calculator Data Assistant for the Farm Carbon Toolkit (FCT). I can imagine if you don’t work for FCT, you may not know who I am. I tend to work in the background, assisting the passionate and driven people who do great work in helping farmers to meet their low carbon and sustainability goals.


Day to day, my activities and tasks can vary widely, depending on the needs of the Calculator team as well as Izzy, our Data Scientist with whom I also work closely.

I primarily work with the Calculator team which can involve a variety of tasks. One of my main responsibilities is the rigorous testing of the Calculator after every update, and following the addition of new items to the calculator. Flagging errors and helping to resolve issues (if indeed there are any!) ensures a reliable tool and the efficient running of the calculator that farmers and landowners can use seamlessly. Another major part of my role is information-finding. Regularly, the Calculator team receives requests for additional products/items/data entries to be added to the calculator. Personally, I was surprised by how many crop protection products (insecticides/herbicides etc.) that are available to farmers, upwards of 30,000 different products available in the UK alone. So you can imagine, with changing trends and needs of farmers to protect their crops in various ways, we as a Calculator team need to keep up with adding additional products to the calculator.

Outwith helping the smooth running of the calculator, my responsibilities include assisting Izzy, our Data Scientist, with her work. Recently, I’ve been assisting her in updating and maintaining soil sampling datasets using QGIS (a spatial data software) that have been collected by the advisory team. I also assist Izzy by testing apps that she designed herself! One of which is a soil sampling app for use by the FCT Advisory team to record soil sampling points more efficiently. I’m particularly grateful for this piece of work as it takes me away from my desk and gets me walking around, albeit on the streets of Edinburgh rather than the fields.

My day to day can vary depending on the tasks that are required or whether I’m working out of my flat, a cafe or the Melting Pot, the co-working space I go to. I’m kept on my toes with the diversity of work to do. Through this type of work, it might seem easy to disassociate from the real-world challenges faced by farmers in a changing climate when you’re spending your days hidden behind a screen, focused on numbers and code. However, this is what I feel FCT does very well, in connecting us to the issues we are all helping to solve. Between the numbers and spreadsheets, we do well to have numerous meetings, whether it be online, hearing about the projects FCT are involved in such as Farm Net Zero, or in person days where we celebrate the farmers that are doing the most to demonstrate low-carbon, sustainable agriculture.

My first in-person day was last September at our annual field day, where FCT presented the Carbon Farmer of the Year. An opportunity to hear first-hand what farmers are implementing to produce our food in a sustainable and low-carbon manner with the help of our carbon calculator. I always come back from these days feeling invigorated to tackle the next challenge knowing that farmers are using the calculator to benefit their farms and the environment. 

Methane Inhibitors in Ruminant Diets and their impact on Greenhouse Gas Emissions

Written by Tim Dart / Project Manager, Farm Carbon Toolkit

This article reviews the mechanisms and inputs to ruminant diets which are known to impact greenhouse gas (GHG) emissions. It explores how these can be used by ruminant livestock farmers, alongside their limitations and the need for more research into more systems-based approaches to reduce methane emissions from ruminants.

Background

Methane (CH4) is an important greenhouse gas in livestock-based agriculture as it is particularly potent. Over a 20-year period, methane is approximately 80 times more powerful at heating the earth than carbon dioxide (CO2), though it dissipates much more quickly (7-12 years) compared to CO2.  Because methane is such a potent greenhouse gas, anything that can be done to reduce those emissions cost-effectively and without negative impacts on animal health, welfare and productivity is beneficial. 

Ruminant animals have diverse microbial populations in their stomachs and these form a natural ecosystem in their own right. Anaerobic fermentation is a key process in the digestion of natural forage-based diets. Methane is released by anaerobic microbial activity through a process called methanogenesis and is consequentially released into the atmosphere as a by-product of digestion. Methane production also results in a loss of gross ingested energy and reduces animal growth and development, so minimising methane production can in theory lead to an increase in animal growth and productivity. 

All ruminants (cattle, but also sheep and goats) together, contribute 30% of global methane released into the earth’s atmosphere. While this briefing focuses on methane inhibitors in ruminant diets, there are also opportunities to reduce methane emissions post-digestion, such as through manure and slurry management, biodigesters and activity to increase dung beetle activity. This will be the focus of a forthcoming briefing. Strategies to reduce enteric methane production are a major focus of research, due to the significance of methane. Initiatives like the Global Methane Hub are leading work on increasing our understanding of the mechanisms for reducing methane production safely in ruminants. Feasible approaches include improved animal and feed management, such as diet formulation, which has shown potential for meaningful emissions reductions. This is an active area of interest for organisations such as the Farm Carbon Toolkit (FCT) alongside our work on strategies to reduce enteric methane production post leaving the digestive system.

The commercial backdrop

FCT is aware of the significant ongoing efforts to develop products aimed at reducing methane emissions. Much of this work has focused on supplements that can be added to the animal’s diets, as these offer clear commercial opportunities for manufacturers. However, generating robust scientific data to support solutions based on practice changes, rather than commercially sold products, has been more challenging. As a result, these approaches and beneficial practices are underrepresented in discussions about methane reduction, due to the current lack of robust evidence demonstrating their effectiveness. 

Adding supplements to ruminant diets becomes difficult to achieve when those animals are consuming a forage-based diet, grazing in the wider environment and consuming a variable and diverse range of plant species. In these situations, research into the makeup of these forages which can reduce emissions is taking place, but with no patentable product to promote, the investment in research and development is understandably less intense. As such, FCT as a farmer-led community interest company, may have a legitimate role in seeking to facilitate and advance the science in this area of research and development.

Feed supplements are now becoming commercially available in the UK. The most common supplement currently is 3-NOP (Bovaer®) which has drawn the attention of the media in recent weeks. There are thought to be other products in advanced development that are now close to market. There are other strategies and approaches where scientific data has established methane inhibitory activity which we discuss below.

Current understanding of Methane Inhibitors and their mode of action

Bovaer®

Bovaer is a synthetically manufactured enzyme inhibitor with an active ingredient called 3-Nitrooxypropanol (hence 3-NOP Bovaer). It is scientifically referred to as a Methyl co-enzyme or M reductase Inhibitor, meaning it blocks the activity of a combination of enzymes that breaks down organic compounds (under anaerobic conditions found in the rumen) and therefore prevents the final biochemical stage of methane release. It is called a reductase process (a reduction process) that would normally result in the breakdown of a glucose chain (a sugar) into CH4 (a methane compound). 3-NOP inhibits that activity.

The Food Standards Agency Website states:

Bovaer has undergone rigorous safety checks by the Food Standards Agency as part of its market authorisation process and is approved for use, and is considered safe for the consumers of milk and beef. It has been demonstrated to be safe for the animal, consumers, workers and the environment.

The dosage of Bovaer is recommended at 1 gram per 20 kg of feed (label recommendation). The manufacturer claims that a 45% reduction in methane emissions for dairy cows and 30% for beef cattle, is achievable, but only when the supplement is fed within a blended or total mixed ration.

Seaweed

Microalgae, commonly known as seaweed, are a large group of marine plants, made up of three relevant taxa: Rhodophyta (red), Chlorophyta (green) and Phaeophyceae (brown). Bromoform is found in the highest concentrations in red seaweed Aspargopsis, which is grown in subtropical regions around the world. Brormoform is also found in lower concentrations in the brown and green seaweed groups which are more ubiquitous and widespread in the world’s oceans. Feed additives derived from Asparagopsis have reduced methane emissions by 40+% and 90% respectively.

Bromoform (CHBR3) has proven to be highly effective at inhibiting methanogenesis along with other halogenated volatile organic compounds. These VOCs effectively bind to enzymes and reductases, reducing H2 and CO2 release and through archaeal organisms these produce CH4. 

There are some studies and claims that Bromoform promotes increases in animal productivity, but other studies report modest reductions in milk yields (-6.5%) this appears to occur when reductions in animal intakes of feed are also observed. There has also been some evidence of abnormalities of the rumen walls of participating animals in such studies, with the loss of papillae and microscopic inflammation found in two studies, although the studies were not able to directly conclude that damage to the rumen was as a result of A.taxiformis supplementation. It is clear that there are discrepancies within the results of the various studies undertaken using Bromoform and that the energy in the H2 compounds resulting from the reductase reaction is not 100% possible to be re-diverted into volatile fatty acids and appears to require the expansion of H2 sinks within the rumen and is seen as an area of further developmental work.

There are numerous other bioactive compounds within the microalgae plants / seaweeds, and are known to produce other compounds that have anti-microbial function that could modify the rumen environment and reduce methane emissions in different ways. These include; phlorotannis, saponins, sulfonated glycans and other halocarbons and bacteriocins, these are the source of ongoing research and developmental work.

Condensed Tannins

Condensed Tannins (CT’s) are commonly found in high concentrations in various UK native flora, including Greater Birdsfoot Trefoil, Birdsfoot Trefoil and Sainfoin. These are all commonly found in herbal leys. CT’s are complex plant polymers of polyphenols found in legumes and other C3-type plants. CT’s are considered to reduce methane emissions through the following mechanisms:

  • Reducing fibre fermentation
  • Inhibiting the growth of methanogenic micro-organisms
  • Acting directly against hydrogen-producing microbes.

CT’s are able to bind to proteins, polysaccharides and metal ions and inhibit fibre digestion of longer-chain starch, cellulose and hemi-cellulose. As such CT’s consequently reduce the formation of hydrogen and acetate and inhibits the growth of methanogenic microorganisms, thus reducing enteric CH4.

Excessive inclusion of biologically active Condensed Tannins within ruminant diets have been found to be detrimental if it exceeds 6% of the overall animal diet in terms of dry matter intake (DMI). Elevated levels have been found to impact negatively on animal performance in terms of growth rate or milk yield. Target inclusion of CT’s are recommended to between 2 and 4% where improvements in animal performance can be achieved. The scientific quantification of the impact of CT’s on Methane emissions is not clear, with the research inconsistent with the work that has been published to date, but it is not considered inconsequential.

From other parts of the world, studies (predominantly Australia) are being undertaken on management practices and cattle browsing legumes known to hold high levels of Tannins, Desmanthus or Leucaena species. Leuceana is a tropical and sub-tropical legume fodder crop and Desmanthus is a tropical legume. The inclusion of both crops in ruminant diets has been shown to improve live weight gains and reduce methane emissions in cattle.

Diversity and grazing diets

By embracing the diversity of grazing diets, there is potential to reduce ruminant emissions through a whole-systems approach. This involves increasing the overall dietary content of tannins coming from multiple grazed forage species, such as herbal leys, willow and other silvopastoral feeds. This can achieve a measurable and meaningful reduction in enteric methane production. However, achieving this requires investment and expansion of knowledge and empirical quantification.

Other options

Other options for exploring enteric methane production, including but not exhaustively:

  • Genetic selection 
  • Vaccination
  • Feeding of grape marc (which is high in Tannins)
  • Adding nitrate or biochar to feed

Conclusion

This is a dynamic area of development and knowledge exploration on GHG emissions, with many complex interconnections to broader environmental concerns. It is important to recognise these links, which include, but are not limited to, animal welfare, animal longevity, as well as other sustainability factors such as biodiversity, water quality, air quality. These, along with other far-reaching sustainability goals, must be carefully balanced to inform the best possible decisions.

How Introducing Pulses into UK Arable Crop Rotations Could Reduce Emissions

Agricultural emissions could potentially be reduced by 3.4Mt CO2e by replacing half of soyabean meal in livestock feed with homegrown pulses as a result of reduced deforestation and land use change, lower synthetic fertiliser use and fuel savings. We are delighted to share more detail with you here.

In 2023, only 6.3% of the UK’s 4.3 million hectares of cropping land grew beans or pulses. These crops have significant agricultural potential; offering soil health benefits, livestock feed options, and alternatives to currently stressed rotations. The NCS project hopes to harness this potential by expanding the pulse cropping to 20% of the total arable area in the UK. This would involve increasing the annual area of beans and pulses grown from 275,090 ha’s (6.3%) to 874,026 ha’s (20%).

The impact of expanding pulse cropping

Expanding the pulse cropping area will result in GHG emissions reductions in the areas highlighted
below:

  • Reduced fuel usage
  • Direct fertiliser avoidance
  • Indirect fertiliser avoidance as a result of leguminous residues
  • Providing a low emission feed alternative to imported soya

Reducing fuel usage

Growing and harvesting pulses requires less fuel than growing cereal crops. FCT modelling on the operations needed to grow cereals indicates that 91 litres of diesel/ha is required, compared to 84 litres/ha to grow beans and pulses. This reduces emissions by 37,524.09 tCO2e when scaled out across the UK arable area.

Reducing fertiliser reliance

Growing pulses like peas and beans reduces reliance on synthetic nitrogen fertilisers both during the pulses cropping year and for subsequent crops, as these plants fix nitrogen into the soil. In 2023, the UK applied an average of 125 kg N/ha of fertiliser, totalling 546,266 tonnes and emitting 3.6 MT CO2e. By expanding pulse cultivation, the UK could save 74,867 tonnes of nitrogen fertiliser annually, directly avoiding 494,925 tCO2e emissions. Moreover, pulse residues can enhance nitrogen availability for subsequent crops, amounting to 35–70 kg N/ha (depending on soil conditions etc.). This could save an additional 20,963–41,926 tonnes of nitrogen annually across the UK, equating to 138,580-277,160 tCO2e.

Substitution of imported soya feed

In 2023, the UK imported 2.37 million tonnes of soya feed, 74% from South America, resulting in 7.3 MT CO2e emissions. UK grown beans could replace some of this soya, substantially reducing the footprint of animal feed. If all UK grown beans within the scenario proposed by NCS were used within compound feeds and straights, they could replace 96% of soya imports, avoiding 5.3 MT CO2e.

A more realistic scenario is replacing 50% of imported soya with 1.95 million tonnes of UK
beans, requiring 454,468 hectares (52% of beans/peas cropping area). This would cut
feed emissions to 4.5 MT CO2e, saving 2.8 MT CO2e compared to current levels of soya imports.

Conclusion

The expansion of beans and pulses to cover 20% of the UK cropping area could save 3.4
MT CO2e (equivalent to 7% of UK agriculture’s total emissions). This would increase if more
of the beans and pulses grown could displace imported soyabean meal.

Sources:

  • Fertiliser data from the British Survey of Fertiliser Practice, 2023
  • Land use data from DEFRA land use and crop areas 2023
  • Fuel usage based on FCT modelling of the field operations
  • Soya imports from EFECA and UK soya manifesto, 2024 progress
    report
  • Protein content: Johnston et al, 2019 https://doi.org/10.1016/j.
    livsci.2018.12.015

Bringing new and novel fertilisers into Calculators: a call for further collaboration 

This month marks a year since the publication of the ‘Harmonisation of Carbon Accounting Tools for Agriculture’ report commissioned by Defra and produced by ADAS. 

The collaborative efforts of the three leading carbon calculators resulted in significant progress being made, especially in the area of harmonisation on methods to bring new and novel fertilisers into our Calculators.

An opportunity for harmonisation

Commissioned by Defra in 2022, the independent ADAS report sought to explore the level of divergence in carbon assessments between carbon calculators and provide recommendations for harmonisation, with the ultimate goal of ensuring comparability of results between the different providers. As the report states:

It is not about identification of which calculator is better or worse than others. It is intended that the insights from this analysis will help inform a potential approach that will enable providers to develop their calculators in a way that creates increased comparability of results while still allowing innovation.

Successful collaboration

In response to the publication of the report, three of the UK’s major carbon calculators – Agrecalc, Cool Farm Tool, and the Farm Carbon Calculator – agreed to work together in June 2024 to harmonise their calculator methodologies, on the understanding that such work would ultimately benefit all their end users. 

Since that initial meeting, we are pleased to report significant progress on one area of divergence identified by ADAS between the different calculators reviewed, namely fertiliser embedded emissions.  In addition, we are working on Calculator interoperability to enable data transfer between Calculators.

We have recently established an Industry Fertiliser Steering Group to explore how new and novel fertilisers with lower carbon footprints should be incorporated into all carbon calculators. This work is being kindly supported by the Agriculture Industries Confederation (AIC). With a range of new and novel fertilisers being developed and introduced into the UK, it is important that any emissions reductions brought about by these products can be accurately accounted for by the calculator tools. 

Join us

Following the successful collaboration between Agrecalc, Cool Farm Tool, and the Farm Carbon Calculator, we are keen to invite other calculator providers who also publicly provide transparency in their calculator methodologies to join us on this harmonisation activity.  Liz Bowles, CEO of Farm Carbon Toolkit said:

We are keen to support all Calculators who wish to work together for the benefit of the agricultural sector.

Our mutual goal is collaboration with industry, trade bodies, and fellow calculator providers in the UK and internationally, so that we can actively contribute to the development of more consistent approaches to on-farm carbon calculation, for the ultimate benefit of our varied customers. We look forward to hearing from you.

Additional Information

This positive, collaborative work has come about as a direct result of the ADAS report commissioned by Defra. Further information on the report is set out below, together with some key aspects to assist everyone in the agri-food sector to understand more about how farm-based greenhouse gas emissions are estimated.

The purpose of the ADAS work

This project was developed to quantify the level of divergence in the calculation of farm-level emissions between a selection of the main carbon calculators on the market, understand the causes of this divergence, and determine how those differences might impact the user. By its nature, the report focuses on the differences between calculators and the challenges of providing robust estimations while making the process accessible to non-expert users. 

However, as the report states:

It is important to recognise that despite these challenges the calculators are all able to provide the farmer with a baseline understanding of emissions and can facilitate the start, and ongoing development, of a decarbonisation process.

Fundamentals of all Farm Carbon Calculators

As the report states:

all carbon calculators are models; there is no single correct answer as they are aiming to simplify a complex biological system

However, it is important to understand why there are differences in results between calculators and identify ways to minimise these differences. 

Harmonisation of calculators aims to ensure greater levels of precision of outputs, while recognising the need to simplify data entry to support the use by non-expert users (e.g., farmers), in order to facilitate the provision of consistent guidance to farmers to support their decarbonisation efforts.

Findings of the work

The report did not recommend any one calculator as being superior to the other calculators investigated. Indeed, what has become clear is that different calculators ask different questions and there is currently no one standard question. 

It is important for farmers and growers to look at how individual calculators work for them in providing results at a product, enterprise or whole farm level and seek one which meets their specific needs. The report set out the main areas where ADAS found differences between how the calculators dealt with different types of emissions and how the boundaries for such measurements were set.

Conclusions

It is clear that there is still much work to be done by all calculators to ensure they remain aligned with emerging guidance as this science develops and matures. The good news is that data standards harmonisation is underway, driven by the tool owners themselves. 

While there continues to be a range of different user and supply chain requirements for a farm carbon footprint (from corporate scope 3 reporting and risk management planning to product footprinting and on-farm resilience planning) there will be an ecosystem of different tools and providers to meet this range of needs. One size does not fit all in this space!

To identify which Calculator might suit you best, AHDB has set out a useful set of questions to guide you: Carbon footprint calculators – what to ask to help you choose | AHDB

Notes to Editors

As the UK agricultural supply industry’s leading trade association, the Agricultural Industries Confederation (AIC) represents businesses in key sectors within the supply chains that feed the nation.

Its Member businesses supply UK farmers and growers with animal feed, fertiliser, seed, crop protection products, trusted advice and quality services that are essential to producing food, as well as trading crops and commodities across the globe.

Formed in October 2003 by a merger of three trade associations, today AIC has over 230 Members in the agri-supply trade and represents £17.8 billion* turnover at farmgate.

AIC works on behalf of its Members by lobbying policymakers and stakeholders, delivering information, providing trade assurance schemes, and offering technical support.

www.agindustries.org.uk

*According to a 2023 survey of AIC Members.

Farm Carbon Toolkit is an independent, farmer-led Community Interest Company, supporting farmers to measure, understand and act on their greenhouse gas emissions while improving their business resilience for the future.

The Farm Carbon Calculator uses the IPCC 2019 and UK GHG Inventory methodologies and is aligned with the GHG protocol agricultural guidance.  Recent developments have allowed us to provide greater interoperability with other data platforms through our Report Export API and Carbon Calculation Engine API. This represents a step-change in the industry’s ability to provide trustworthy carbon footprints with transparent methodologies on platforms where farmers already collect data, thus reducing the data inputting onus on farmers. This new functionality has been warmly welcomed by supply chain businesses who are now using our Calculation Engine to support their customers without the need for further data entry.

The Farm Carbon Calculator is used across the UK and on four continents with global usage growing at around 20% per year.

For over a decade, Farm Carbon Toolkit has delivered a range of practical projects, tools and services that have inspired real action on the ground. Organisations they work with include the Duchy of Cornwall, First Milk, Tesco, Yeo Valley and WWF. The Farm Carbon Calculator is a leading on-farm carbon audit tool, used by over 8,000 farmers in the UK and beyond. To find out more visit www.farmcarbontoolkit.org.uk  

Media contact: Rachel Hucker ([email protected] 07541 453413)

Agrecalc, a carbon footprint tool developed by combining practical expertise with world-class agricultural science, is a precise instrument that offers both breadth and depth of on-farm and through-the-supply-chain calculations of GHG gas emissions.

Agrecalc is the largest source of collated farm benchmark data from thousands of farms, having been used as the designated tool to deliver carbon audits under various schemes since 2016. It is recognised as the preferred carbon calculator in many of the emerging government programmes.

With a mission to increase efficiency and business viability of food production, the scientists, consultants, and developers who work on Agrecalc, strive to constantly upgrade the calculator according to the most up-to-date available research results and recommendations.

Media contact: Aleksandra Stevanovic, Head of Marketing; ([email protected]; 07551 263 407)

Cool Farm Alliance is a science-led, not-for-profit membership organisation (community interest company) that owns, manages, and improves the Cool Farm Tool and cultivates the leadership network to advance regenerative agriculture at scale.

For over fifteen years, the Cool Farm Alliance has worked to put knowledge in the hands of farmers and empower the full supply chain to understand and support agro-ecological restoration by providing a respected, standardised calculation engine to measure and report on agriculture’s impact on the environment. The Cool Farm Tool has established widely endorsed, science-based metrics for water, climate, and biodiversity, supported in 17 languages and used in more than 150 countries around the world.

Cool Farm Alliance members share the need for a respected, consistent, standardised, independent calculation engine and have joined the Alliance to ensure the Cool Farm Tool meets this need, now and in the future.  To find out more visit https://coolfarm.org/

Media contact: Kandia Appadoo ([email protected])

Green Claims Relating to Carbon

Written by Grace Wardell/Calculator Development Officer

Due to an increasing awareness of climate change, more people than ever are interested in the environmental impact of the products they’re buying. But how many of the claims around carbon are true and how can we trust them? The UK Green Claims Code suggests that 40% of green claims made online could be misleading1. As a farm business, it is particularly important to ensure that claims made around carbon or greenhouse gas (GHG) reductions and removals are truthful and transparent. Whether you’re being offered ‘low carbon’ fertilisers or want to promote your GHG reductions, navigating green claims can be tricky. 

We know this can feel scary, no one wants to be accused of greenwashing. If you’re looking to make positive environmental claims about your farm, we would advise keeping a record of your working with evidence to back it up. We’ve laid out some key terminology to help get you started with carbon accounting, how you can market it and how you can evaluate the green claims of products you buy.

What are green claims? 

Green claims (also sometimes called ‘environmental claims’ or ‘eco-friendly claims’) are often made by a product or business that claims a benefit to, or a reduced impact on the environment.

Some examples of green claims include: 

  • “This product will reduce the carbon footprint of your farm”
  • “Company’s environmental footprint reduced by 20% since 2015”
  • “CO2 emissions linked to this product halved as compared to 2020”

How can carbon footprinting help?

Carbon footprinting is the first step to making green claims about your business or a product you’re selling. In order to reliably report changes in GHG emissions, you first have to estimate them. Conducting a carbon footprint can highlight ‘hot spot’ areas in your business which might be emitting more GHGs than you thought. Addressing these ‘hot spot’ areas and reducing emissions associated with them is often an easy first win in the journey to lower emissions, net zero and even financial savings. You can try out our carbon calculator tool, which is free for farmers and growers. You will then need to record your GHG emissions estimate in subsequent years. Once you have evidence of reduced emissions over time, you may want to promote this, for example on a product you sell or as a business. Here are some key terms to get familiar with.

Key terms

Reduced emissions refers to the direct lowering of GHG emissions by adopting more sustainable agricultural practices, technologies, and management strategies. These reductions involve minimising the release of GHGs that occur during conventional farming activities. Looking at ways to reduce GHG emissions is the first recommended step before you seek to make any “green claims”.

Example: A farmer adopts precision agriculture techniques to apply fertilisers more efficiently (e.g., using soil sensors, variable rate application, or slow-release fertilisers).

Impact: By optimising fertiliser use, the farm reduces the amount of nitrous oxide (N₂O) emissions, which are released when excess nitrogen is applied to the soil. Improving nitrogen use efficiency can directly reduce N2O emissions.

Avoided emissions refer to GHG emissions that would have been released into the atmosphere under business-as-usual practices but are prevented through changes in farming methods, land use, or supply chain activities. These emissions reductions do not remove carbon from the atmosphere directly, but rather prevent emissions from occurring in the first place. It’s very similar to “reduced emissions” but it is more hypothetical.

Example: A distributor uses biofuel from used cooking oil to transport their products (renewable energy source) instead of using diesel.

Impact: High emissions that would have been released from burning diesel or during transport are avoided. This distributor may have lower GHG emissions from transporting the same quantity of goods the same distance as compared to a distributor using diesel. However they may require more biofuel to transport the same quantity of goods the same distance so the avoidance of emissions is not guaranteed.

Carbon Removals is the process of actively removing CO2 from the atmosphere and storing it for a long time, using either technology or nature-based solutions. In a farming context, this is mostly done by natural sequestration of carbon into soils, trees and other biomass. These removals can help offset GHG emissions, making them a critical component of climate change mitigation efforts in agriculture.

Example: A farm establishes hedgerows along field boundaries, which serve as natural windbreaks and biodiversity corridors.

Carbon Removal Mechanism: Hedgerows sequester carbon in plant biomass and enhance soil carbon storage along the boundaries of agricultural fields.

Impact: In addition to carbon removal, hedgerows provide habitat for wildlife, improve soil health, and protect crops from wind and erosion.

Carbon insetting refers to reducing GHG emissions – or increasing carbon storage – within a company’s own supply chain, focusing on sustainability improvements that benefit the company’s own production processes and stakeholders. Whereas carbon offsetting involves reducing GHG emissions – or increasing carbon storage – outside of the companies supply chain, often by purchasing carbon credits from environmental projects, such as tree planting. With carbon offsetting, the reduced emissions, or enhanced carbon storage, occurs elsewhere and is therefore harder to track. Read our detailed explanation of carbon insetting and offsetting on our getting paid for carbon page.  

When entering into any carbon insetting or offsetting agreement, try to ensure there is a clear definition of the project, who is responsible for claiming the GHG reductions and where those reductions are taking place. These principles can ensure there is clear evidence of where GHG reductions are coming from and can help prevent the double counting of emissions reductions.

Assessing green claims on products you buy

You might have come across “Low Carbon” products, one example of this is low carbon fertilisers. Traditional nitrogen-based fertilisers (e.g., ammonia, urea) are energy-intensive to produce, mainly due to the reliance on fossil fuels for the Haber-Bosch process, which converts nitrogen from the air into ammonia. Improvements in technology have now produced Green ammonia, manufactured using renewable energy (solar, wind, hydropower) to generate hydrogen through water electrolysis, instead of using fossil fuels. This significantly reduces the carbon emissions from fertiliser production. Alternatively, Blue ammonia is ammonia still being produced using fossil fuels, but incorporates carbon capture and storage methods to remove CO2 produced during the process. Blue ammonia still relies on the heavy use of fossil fuels, whereas green ammonia reduces this demand. 

Urease inhibitors are an example of a GHG mitigation product that can reduce ammonia emissions associated with urea fertilisers. Urease enzymes are naturally present in soil and are involved in the process of changing urea into ammonia and carbon dioxide. This means that when urea is applied to soils, a significant loss of nitrogen occurs as ammonia is released into the atmosphere, resulting in air pollution. Urease inhibitors are added to urea-based fertilisers (sometimes known as protected urea) to slow down the enzymatic process, keeping more nitrogen in the form of plant-available ammonium for longer and increasing the fertiliser efficiency. New rules in England (2024) have outlined when unprotected/uninhibited urea can be applied, check out this AHDB article to see how it may affect you.

Another example of a GHG Mitigation product are methane inhibitors for ruminant animals. Methane inhibitors are feed additives designed to reduce methane emissions produced during digestion, specifically in the process known as enteric fermentation. The goal is to prevent or slow down the final step in the fermentation process where methane is produced without harming the animal’s digestion or productivity. A methane inhibitor feed additive (Bovaer by DSM-Firmenich) has been approved for use in the UK that on average claims a 30% reduction in methane emissions for dairy cattle and 45% reduction for beef cattle2. It is worth noting that the efficacy of these products can vary across different feeding systems and therefore may not always be a ‘silver bullet’ to reducing methane emissions. 

Provenance

“Farm washing” by big UK supermarkets often leads people to believe that they’re buying products grown on small family farms within the UK, however a lot of this produce originates overseas or from big industrial scale farms.

Riverfords recent ‘Farmers against Farmwashing’ Campaign showed that 74% of shoppers want supermarkets to be transparent about produce and meat that is not British and sourced from abroad. When shoppers were shown a photo of produce in a UK supermarket under a Union Jack flag, 68% of people expected more than half of it to come from a British farm, when in fact, none of it did. 

Supermarkets have been called out before for marketing these fake farm brands that sell imported produce under a fictitious farm name and even a Union Jack flag. As a consumer, you can always check the fine print on produce packaging to see where it originates and don’t just rely on branding.

Case Study: I’ve got a Life Cycle Assessment for a product I buy in, can I use it in my carbon footprint?

For inputs on your farm, you may be buying products that come with their own associated carbon footprint and want to know if you can incorporate this into your business’s carbon footprint. Let’s work through an example.

The feed you buy your dairy cows has a life cycle assessment (LCA) carbon footprint that has been passed onto you by the company selling this product. 

  • Always check that the product LCA you have is for exactly the item you have purchased. The functional unit in this example would most likely be for 1 kg feed wheat and not a derivative of that, for example 1kg of white flour. Different products will have different processes involved that generate emissions, we can’t always assume that just because the products are similar, they will have a similar carbon footprint.

Check the methodology of the LCA to understand how it has been generated and what the uncertainties around it are.

For example, the feed wheat claims that it has a negative emissions factor (-1.2 kgCO2e/ kg wheat), i.e. the production of it has sequestered more carbon than it has generated. The LCA claims that this is due to using regenerative practices to grow the wheat which has enhanced soil carbon stocks. However, when you look at the methodology, it lists that carbon sequestration was not measured by direct soil measurements, but was instead modelled with Intergovernmental Panel on Climate Changes (IPCC) methodology Tier 1 approaches (see Box 1). 

  • If the product you are buying claims to have a negative emissions value, then the methodology needs to be based on direct soil carbon or GHG measurements on that farm. If a direct measurement of sequestered carbon can be provided, this increases the reliability of the claim and can be passed on to a company which could include it as part of its scope 3 emissions inventory. 
  • The choice of methodology will impact the reliability of the results. For example, there are three IPCC tiers to the recommended approaches (see Box 1). If direct soil measurements are taken, this would be a tier 3 approach and is the most reliable method, however the methodology uses a tier 1 (global) approach with estimated carbon stocks. 

Check how the carbon footprint is reported.

  • Ensure the carbon emissions are reported separately to any carbon removals the company claims – not just the carbon balance (i.e. emissions – removals). There is a requirement by carbon reporting guidance to separate these two values. It is mandatory to report emissions, but not removals, due to the uncertainty around them. 
  • Check the units that it is reported in (usually kg CO2e / kg product) and ensure that this makes sense for the way you will use the product. 
  • Has the footprint been validated externally by third party verification? Although this is not absolutely necessary to have a reliable product footprint, it can help add confidence that the methodology has been checked by others. 

If you are satisfied that the LCA has supplied a clear methodology on how the carbon footprint has been calculated, you may wish to include it as part of your scope 3 emissions report. 

Box 1. IPCC Methodologies for Calculating GHG Emissions

Tier 1: This is the most basic approach, using default emission factors and generalised activity data provided by the IPCC for different sectors. It mostly uses global data and is intended for broad estimates with low accuracy.

Tier 2: This approach uses country- or region-specific emission factors and more detailed activity data, such as local energy usage. It improves accuracy compared to Tier 1 by incorporating factors that are more relevant to the specific conditions of the region.

Tier 3: The most advanced method, using detailed modelling or direct measurements and highly specific data for the particular circumstances of the country or sector. Tier 3 provides the highest level of accuracy by incorporating real-time data, complex models, and system-specific emission factors.

Each tier increases in complexity, accuracy, and the level of data required.

Pointers on how to sense check and provide robust environmental claims

The competition and markets authority has set out six principles for businesses to follow when making green claims and provided examples to help you assess green claims3. Here we have summarised the principles with examples:

  1. Is the claim truthful and accurate?
    • Check the facts: Verify that the environmental benefit being claimed is backed by credible evidence. Look for data, scientific studies, or certifications that support the claim.
    • Avoid exaggeration: Ensure that the claim reflects the actual impact of the product or service and is not overstating the environmental benefits.
  1. Is the claim clear and unambiguous?
    • Does it go beyond using generic phrases like ‘green’ and ‘eco-friendly’ and list the specifics of how it is an improved product? 
  1. Does the claim omit or hide important relevant information?
    • This may be hard to know and would probably involve doing a little bit of research around the product and its production methods. 
    • For example, a product with ‘save our seas – these are microbead free’ makes you believe that similar products may contain microbeads – however microbeads are banned in the UK, and therefore shouldn’t be in any of the products!
  1. Does the claim make fair and meaningful comparisons?
    • If a product is claiming to be better than others on the market, how has this been assessed? Has the comparison included a wide range of alternative products?
  1. Does the claim consider the full life cycle of the product or service?
    • Life cycle assessments show the overall impact of a product from cradle to grave.
  1. Is the claim substantiated?
    • An example of a substantiated claim might be: “Our product packaging is made from 100% recycled materials and is fully recyclable. By using recycled materials, we have reduced our packaging-related carbon footprint by 40% compared to virgin plastic packaging. This reduction has been verified through a third-party Life Cycle Assessment (LCA) in compliance with ISO 14040 standards.”

References 

  1. UK Government. The Green Claims Code. Available at: https://greenclaims.campaign.gov.uk/. Accessed [07/11/2024].
  2. DSM-Firmenich (2024). Bovaer. Available at: https://www.dsm.com/anh/products-and-services/products/methane-inhibitors/bovaer.html. Accessed [07/11/2024]
  3. UK Government, Competitions and Market Authority. Making Environmental Claims on Goods and Services. Available at: https://www.gov.uk/government/publications/green-claims-code-making-environmental-claims/environmental-claims-on-goods-and-service Accessed [07/11/2024]

Case Study: Ben Richards, Middle Trelan Farm, Cornwall

Ben Richards
Video courtesy of Innovation for Agriculture

Ben Richards has been awarded Third Place in the 2024 Soil Farmer of the Year competition. This case study gives an overview of how Ben has built his system around resilient soils to provide the forage and nutrition his herd. If you would like to visit Ben’s farm, a farm walk taking place on 12 September 2024: click here to book your place.

Middle Trelan Farm is a 290-acre dairy farm in Cornwall, milking 180 to 200 cows, depending on the time of year. The farm has been certified organic since 2020, with the cows being 100% grass-fed, milked once a day, calved in spring from the 10th March and outwintered to reduce costs. 

Soil management has been a key focus on the farm for over 20 years, and Ben shares that making more money has consistently been a key driver in the steps taken to improve soil health and reduce inputs. 

Ben Richards

Early noughties – addressing nutrient imbalances and surface compaction  

As a wet farm with heavy clay soil, an early challenge in soil management was to alleviate surface compaction, which was achieved using slit aeration. 

Ben also took advice from Straight Line Nutrition, using recommended fertilisers to resolve nutrient imbalances in the soil. 

2010s – phasing out chemicals and introducing herbal leys  

Weaning off chemicals has been a gradual process at Middle Trelan Farm. In 2012, the decision was made to start gradually weaning off the high use of nitrogen fertiliser. Now, Ben focuses entirely on feeding the soil, not the plants, which he does by applying 2.5 tonnes/acre composted farmyard manure per year.  

Having switched from blanket spraying to spot spraying broadleaf weeds in 2005, spraying was stopped altogether in 2016. It took four to five years to increase dock beetle numbers to the point where they were controlling docks. Now, with the overall reduction in chemical use, the docks have become more palatable, so what the dock beetles do not eat the cows will eat anyway. 

Ben also started growing herbal leys in 2016, selecting species to benefit the soil, as well as those which will benefit the cows. This includes choosing deep-rooting species to improve the soil structure and enable water to permeate into the soil. Seed companies warned that cows would not eat some of the plants, such as sweet yellow blossom clover, but in practice, Ben has found that as the soil has improved and plants become more palatable as a result, the cows will eat all species. He has not included any ryegrass in the mix for over five years, with the exception of during Covid when the seed companies were not able to source an alternative. 

For reseeding herbal leys, cows are now grazed on the area to be reseeded over winter, followed by pigs. The pigs turn over the soil and root around, preparing the ground for establishing a herbal ley in the spring.      

The cows have benefitted from the move away from chemicals and the introduction of herbal leys, as they can self-medicate by selecting the nutrition they need. The evidence for this is clear, as Ben has not needed to treat the cows with any medications for eight years, although he does still give the calves an anthelmintic for lungworm. 

The phasing out of chemical inputs, from broadleaf herbicides to veterinary medicines has reduced costs and therefore improved farm profitability. 

2020s – moving from a bacterial soil to a fungal soil 

Ben shares that it was 2021 to 2022 when the farm turned around – it had reached the point where it had a fully functioning bacterial soil. The focus has now shifted to move to a fungal-dominated soil, as with fungal mycorrhizal structures present plants can cooperate, warning each other of dangers and contributing to the overall health of the farm ecosystem. 

The presence of deep-rooting plants will facilitate the transition to a fungal soil, so Ben has embarked on an agroforestry project, which is funded by Forest for Cornwall. The project began in 2023 to 2024, when 6,500 trees were planted in 1.5m rows (3 trees across 1.5m), with 12m between rows, which should be close enough for the fungal mycorrhizal structures to reach each other. Grazing trees were selected, including different varieties of willow, poplar and aspen. 

The wettest fields were chosen for tree planting, with the intention that the trees will also help drain the fields, getting rid of surface water. Herbal leys have been planted between the tree rows, so in year two the trees will be grazed together with the herbal leys. 

Another 4,000 trees will be planted this winter. In year three, Ben intends to stop planting and wait to see the impact during a full grazing season, then if it is working as expected he can take cuttings from the existing trees and roll out the system across the whole farm.    

Ben explains that the overall goal of the agroforestry is to maximise dry matter production on-farm to feed the cows, while the trees will also help drain the fields, promote fungal activity in the soil, secure a reliable forage supply throughout the summer and also provide nutritional benefits to the cows eating them. In short, the trees should ‘tick all the boxes’ for farm resilience now and in the future. 

To conclude, Ben shares that he has found it to be true that ‘less is more’. The less interfering he has to do with the cows, the better their life is, and the better his is too.    

Groundswell reflections: how close can agriculture get to being carbon positive?

Groundswell

by Liz Bowles, CEO

Groundswell this year was as exciting as ever, with so many excellent sessions and people to catch up with and meet for the first time. 

There was much interest in how farmers and growers can benefit from the new markets for carbon, biodiversity net gain and nutrient neutrality to name but three, but to my mind, there was far less attention on how the sector can actually reduce the emissions associated with producing food itself.

For me, this is critical as we have to find a way to reduce the greenhouse gases we push into our atmosphere, as well as removing some of the historical emissions already there, if we are to reduce the worst impacts of climate change.

There is, however, a central question for our food system which is: What level of emissions are inevitable from the production of food which is essential for humanity? The Climate Change Committee has come up with a view on this in their 2020 UK agricultural policy for net zero report, which suggests a road map for saving 64% in the annual emissions from agriculture compared to 2017 levels when UK agriculture was responsible for around 58 MtCO2e (12% of total UK  emissions). On closer inspection of the figures though, the actual savings in emissions from agriculture are set at around 21 MtCO2e / year, with the remaining savings to come from forestry, changes to our diet and the production of energy crops instead of food.

This is set out below:

The specific actions suggested for each of these areas are set out below:

  • Tree planting on 30,000 hectares per year
  • Use 10% of UK farmland  for agroforestry (no distinction made between agroforestry and hedgerows)
  • Restore at least 55% of peatland area by 2050. (For lowland peat lands this means rewetting or paludiculture to reduce emissions and for uplands this means rewetting).
  • Increases in low-carbon farming practices for soils and livestock (no detail provided)
  • Increase the area of farmland devoted to energy crops to 23,000 ha per year

From this list, the low carbon farming practices interest me in terms of how their adoption will enable an annual reduction of 10MtCO2e per year to occur (~25% of 2022 UK agricultural emissions). At Farm Carbon Toolkit we work directly with farmers and growers to adopt these practices and changes to current management processes. Typically the areas to focus on include:

  • Planting cover crops
  • Changing crop rotation
  • Transitioning to no/min till where possible
  • Growing new crops
  • Integrated pest management
  • Adopting rotational grazing
  • Planting herbal leys

Across all these practices, there should be a focus on reducing the use of artificial nitrogen fertilisers and purchased livestock feed (especially those including imported ingredients) as both these inputs carry a high level of associated emissions.

Many of these practices can also be considered to be part of the suite of “regenerative farming principles”. Adoption of more regenerative farming practices is growing steadily, but for many farmers, the key question surrounds the financial viability of their adoption when margins are so tight. A recent report commissioned by the Farming for Carbon and Nature Group and funded by the Natural England Environment Investment Readiness Fund (NEIRF) sets out the financial and climate impact of adoption of more regenerative farming practices and systems and includes partial budget information on the financial impact of adoption in England with support from SFI where relevant.

Regenerative farming practices and their financial viability, including external support available in England, where available

This chart clearly shows that with the inclusion of SFI support, many of the practices generally considered to be regenerative are likely to deliver a similar margin than more conventional practices in these areas. The area where more support is needed is in the adoption of more complex arable rotations including pulses and fertility building leys, where even with appropriate SFI payments, the margins from shorter more degenerative rotations are likely to be more profitable. We are a member of the Nitrogen Climate Smart Consortium which is supporting the increased production of pulses and legumes in the UK together with their use as animal feeds to address the need to reduce the use of artificial fertilisers and imported animal feedstuffs. This project will support farmers to do this through farmer field trials as well as the introduction of new technology for on-farm pulses processing.  You can find out more about this project and get involved by following this link.

In summary, I am fairly confident that UK agriculture can reduce greenhouse gas emissions by at least 10% through the adoption of low-carbon farming practices. Indeed through some of the practical work with farmers in which FCT is involved, we are seeing higher levels of emission reductions being achieved within businesses with little or no change in farm output and in many cases increased profitability and business resilience. The element which is mostly missing is the confidence and knowledge to make the necessary changes and knowing where to start.

At FCT we provide a (free for farmers and growers) Farm Carbon Calculator to allow businesses to understand their starting point, a set of tools within our Toolkit to assist businesses to make those chances and a team of expert advisors to talk to.

You can always make contact with us by email [email protected] or by calling us on 07541 453413. We look forward to hearing from you.