Category: Insights

Efficient use of nitrogen on farm

In the face of rising fertiliser prices and environmental concerns, it is crucial to optimise nitrogen use efficiency, NUE, in agriculture. Nitrogen is a key nutrient for crop growth, but on average, only 60% of applied nitrogen is effectively used, while the remaining 40% is lost to the wider environment. This leads to both economic loss and adverse environmental impacts, such as loss of plant ecosystem diversity and waterway contamination.

Reducing reliance on the use of artificial (fossil fuel based) fertilisers is one of the key ways in which all farmers can reduce their farm carbon footprint. Hence finding ways to improve NUE is critical.

How do we go about improving our use of artificial inputs?

1.Improving fertiliser management

The first step in fertiliser management is working out the requirements. Oversupply of nitrogen has many unintended negative consequences:

  1. Reduces soil pH 
  2. Reduces soil  organic matter 
  3. Reduces soil health
  4. Increases nitrogen leaching, run off and volatilisation. 

Fertiliser uptake is most efficient when the right quantity is supplied at the right time , i.e. when the crop can take it up. Regular soil testing and analysis can provide an accurate picture of the chemical composition, providing soil indices for P, K and Mg in line with RB209 and  soil pH. The results from soil testing will be dependent on the legacy effect of previous crops, management and soil type. Standard soil testing does not measure nitrogen content. 

Soil nitrogen supply (SNS) index is used to describe the levels of available nitrogen in the soil. Through measuring the quantity of available nitrogen within the soil, the suggested nitrogen requirement from artificial fertiliser may be reduced due to the supply from the soil alone. Different crops have different nitrogen requirements which are outlined in RB209 with respect to the SNS. These tools can be used to calculate the economic optimum for fertiliser application on each crop. Alongside  fertilisers, optimising pH is critical for most crops to make best use of any fertiliser applied – for most crops it is pH  6.0 – 6.5. Agronomists or FACTS qualified advisors are a good source of fertiliser information and advice.

Timeliness of applications is also an important consideration with split applications being the best way to target the most significant growth periods. Applying nitrogen to a growing crop reduces losses as uptake is at its maximum. With the cost of applications there is an optimum balance for the number of applications on the crop.

Weather is perhaps the biggest determinant of when fertiliser can be applied. The target conditions for soil applied fertiliser are a cool temperature with moist soil. Climate change is becoming a growing threat with more extreme and unpredictable conditions becoming more regular.

Tools to measure Nitrogen

  • Soil Mineral N testing in Autumn or Spring measures plant available nitrogen allowing the grower to adjust the rate of applied nitrogen. This should be done per field and soil type across each field. 
  • Chlorophyll N Tester can be used every 7 – 10 days in most crop types once full leaf ground cover is achieved. e.g. Yara N – Tester
  • Chlorophyll N Sensor mounted on the tractor roof is linked to a variable rate fertiliser spreader or sprayer. Trials have shown a saving of 50 kg of N on wheat is possible.
  • Sap or leaf testing can also be used to measure N in a growing crop.
  • Testing grain and straw for cereals for N and S will allow an accurate budget for N removed and whether there is adequate sulphur which is essential for efficient uptake of N, it will also tell you if you have put too much/enough N on the tested crop.
  • Satellite Imagery, NDVI, can show areas of high and low biomass across fields.

2.       Nutrient management in rotation

The use of cover crops or catch crops can scavenge residual soil nitrogen when sowed after harvest. Nitrogen will be utilised by the plants and stored within the crop until it breaks down and is reincorporated into the soil. These can be used to benefit the following crop by reducing the availability of nitrates to be leached and instead making them available as the residues are broken down. Crops can also be drilled into a standing cover or sown as an understory. This can be particularly beneficial with clover which fixes nitrogen further reducing the demand for artificial nitrogen.

Cover crops are a tool within the wider crop rotation which can be designed with greater diversity incorporating legumes and deeper rooting species to improve the soil structure and residual soil nutrients. By staggering crops with a high nitrogen requirement in a rotation the SNS can be maintained thereby reducing the artificial fertiliser requirements.

Introducing a legume crop into the rotation will facilitate the fixation of nitrogen into the soil which is available for a following crop and will also support improvements in soil health.

3.       Fertiliser application

The method of application significantly influences the distribution and subsequent uptake efficiency of synthetic fertilisers. In the context of solid fertilisers, broadcasting is commonly employed, ensuring a uniform spread across the entire field. This approach is suitable for crops with dense canopies. Other methods for solid fertiliser application encompass placement, band placement, and pellet application. Employing more precise fertiliser application techniques enhances the ability to effectively target the root zone, optimising nutrient uptake but may come at added complexity and cost. When it comes to applications it is important to calibrate the spreader for each product used to ensure accuracy and reduce wastage.

An alternative to solid fertilisers which has experienced a resurgence in recent years, is foliar applications. This approach offers several distinct advantages over traditional solid fertilisers. Foremost among these benefits is enhanced efficiency, largely attributed to the rapid uptake time of products like dissolved urea, which can be absorbed in as little as 5 hours. This improved uptake time provides an additional advantage for alleviating deficiencies in a shorter time period with more flexible and tailored nutrient doses at the correct stage of growth. Additionally, by targeting the plant’s leaves rather than the soil, there is a reduced risk of soil acidification, along with diminished release of volatile compounds. This fosters a more favourable environment for soil biology to thrive and function effectively.

4.       Improving the soil

Soil is a vital component of plant growth and has a huge capacity to improve nitrogen use efficiency through improving the physical and biological components in the soil. A healthy soil is one which promotes plant health and vigour with greater resistance to stress. Healthy soils are more resilient to extreme weather conditions, better able to retain more moisture during droughts and hold more water in periods of high rainfall, thereby reducing waterlogging. Not only does this reduce leaching but it also allows for better uptake of nutrients, including nitrogen, as the soil is coping with a wider range of weather without stressing the crops.

Improving soil conditions facilitates greater biological and fungal activity which improves nutrient cycling, and through interactions with the root zone an enhanced consumption and release of essential minerals.

Increased soil organic matter levels are an indicator of a well functioning soil. Indeed this helps to promote a better soil structure and water holding capacity but it is also a crucial energy source for the microorganisms responsible for nitrogen cycling. The integration of organic manures and composts, where feasible, can significantly augment soil functionality and performance.

To conclude

  • To enhance nitrogen use efficiency, optimal soil conditions are critical. 
  • Ensure any fertilisers are delivered in the right amount, at the right time. 
  • Soil deficiencies should be minimised through sampling and proper nutrient management to allow for maximum uptake of nitrogen. 
  • Consider the use of foliar fertiliser applications to increase NUE at full crop canopy.

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

Sheep – how well adapted are your livestock for your management and environment?

Blog written by Rob Purdew and Hannah Jones

In the absence of sophisticated pharmaceuticals and feed blends, local breeds were historically adapted to their local environment. These adaptations included the ability to withstand weather extremes, the local pest or parasite burden, and the ability to finish on local, often low quality, forage. Local breeds, from Herdwick to Norfolk Horns, were selected for generations and identified as the most efficient livestock for their specific set of conditions.

On the cliff tops of Cornwall, highland cattle are the one of the stalwart cattle breeds for scrub management, where season long grazing results in an average 0.5kg growth rate a day. The same animal in a shed with silage and a more tailored ration will continue to grow at 0.5kg per day with much higher associated costs. Unpicking the carbon footprint integrates the sequestration potential of that scrub, soil management, no bought in feed and the added benefit of habitat provision. The animals may finish older, but as I was told once by a farmer “go for optimum not maximum”, in the scrub environment the highlands were profitable.

A recent event at Trefranck farm, showcasing the innovative work between Matt and Pip Smith with the Castle Vets and Moredun research (funded by Innovate UK) has brought another exciting perspective on sustainability, through the breeding of worm tolerance in Romney sheep. With a careful eye on welfare throughout the project, the first insights into breeding for tolerance to worm load has been unpicked.

Tolerance to worm burden is defined as the ability of a lamb to maintain weight gain irrespective of worm burden. Those lambs with the desirable genetics showed the least growth penalty in the presence of an average worm burden. A comparison of finishing time showed that there was a 10 day difference between the least and the most tolerant lambs. When extrapolated across a whole flock this represents a significant reduction in both forage costs and carbon footprint. This research is driven by the need to address the huge problem of anthelmintic resistance found in roundworms in UK sheep populations, and further incorporates guidelines on targeted selective treatment to ensure the selection of resistant worms in pastures is impeded. Good breeding, alongside good management of pasture environment and animal movement will improve welfare and reduce loss of productivity from worm burden.

Reducing overheads, and your carbon footprint can be achieved by doing the basics –  the right breed in the right environment – and doing it really well.

A Guide to Cover Crops

Cover crops are usually planted within arable rotations between cash crops. They provide a multitude of benefits including building soil fertility, improving soil health and enhancing above and below ground biodiversity.  

As a non-cash crop, it is important to evaluate your soils to identify any issues and decide what you want to accomplish on a field-by-field basis before you sow any cover crops. Species selection should be based on what solution you want the cover crop to provide.

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Above: Cover crops (left to right) oil radish, winter vetch, phacelia and rye

There are many reasons to grow cover crops

Cover crops can offer solutions for soil compaction, fertility building, pest management, livestock feed, cover over winter and more generally, improved soil health.

Addressing compaction issues with deeper rooting species will aid in breaking up the soil and improve porosity, leading to better water infiltration alongside nutrient and gaseous exchange. Incorporating leguminous plants, such as clover, will fix nitrogen, reducing dependency on artificial fertiliser for subsequent crops. Incorporating forage crops into covers which can then be strip or paddock grazed with out-wintered livestock may reduce costs from bought in feed. If arable only, it presents an opportunity to integrate livestock from a neighbouring farm.

Maintaining ground cover and persistence of living roots in the soil can also reduce competition from pests. Certain species of cover crops can even be selected to control the lifecycle of predators. For example, in a Farmer’s Weekly case study, a farmer described his strategy for controlling the population of free-living nematodes that were destroying his vegetables and sugar beet. In this case, a specific oil radish was used that stimulated the hatching of nematode eggs whilst simultaneously providing hostile conditions for their growth, causing slowing and ultimate cessation of nematode reproduction.

Improving soil health

Cover crops are also a useful tool to build stable aggregates to improve soil structure and increase soil organic matter and soil carbon to feed the soil biology. They act as a ‘savings account’, scavenging and assimilating residual nutrients from previous cropping which will then be released upon desiccation for the next crop.

Diversity in cropping is often mooted as a key method to improve soil health and productivity and incorporating cover crops is a fantastic way to introduce much needed diversity into the arable rotation. The idea is that a diverse mix of crops will bring along a diverse mix of rooting types, structures and lengths. Each root will support an array of bacteria and fungi with different apparatus to cycle the nutrients whilst extending and expanding the root network. Above-ground you are also providing a mosaic of solar panels of all different shapes and sizes, keeping the soil covered and maximising the surface area for photosynthesis, utilising the sun’s energy and pumping carbon back into the soil.

Practical tips for establishing and destroying cover crops

For optimum results you need the cover crops to progress quickly therefore warmer soils are usually required – late summer is best for legumes and phacelia, however, brassica and grass species can be sown as late as October. It is good practice to sow multiple species in any one field to optimise competition and gain maximum benefit. This can be especially good for controlling persistent weeds.

Destruction options vary depending on weather, crop type and available machinery. Some cover crops may die off with winter frosts or in hot weather a crimp roller can usually do the job. Ensure a clear plan is drawn out before sowing cover crops and allow a 4-6 week window between destruction and sowing the next crop.  

Using cover crops to increase profit margins

It’s important to think of your bottom-line productivity when assessing whether to go for cover crops. It is an added expense, but the potential savings from reduced inputs could outweigh the additional cost. The benefits of having living roots in the soil all year round, alongside cover to buffer against adverse weather conditions will also improve soil quality, protecting our soils for future harvests and most importantly building business resilience. 

This blog was written by one of our Farm Carbon and Soils Advisors, Tilly Kimble-Wilde. Find out more about her and the rest of the team here.

Cotswold Seeds courses at FarmED 2023

Image taken from Cotswold Seeds website.

Summer/Autumn 2023

The FarmED Programme for 2023 includes a wide range of courses, workshops and events that inspire, educate and connect people to build sustainable farming and food systems that nourish people and regenerate the planet. All take place in their beautiful eco buildings at the heart of their demonstration farm in the Evenlode Valley. Delicious and nutritious refreshments are freshly prepared in the FarmED kitchen.

*Further events will be added to the programme throughout the year. 

Herbal Ley Establishment & Management – June 13th

Join for a one day course on Herbal Leys Establishment and Management brought to you by the FarmED team and Cotswolds Seeds. A herbal ley is a complex seed mixture of grasses, legumes and herbs, which bring a range of benefits to forage, livestock health and soil fertility. Herbal leys can often include a mixture of up to 17 species, and can be incorporated into arable, livestock or horticultural operations with multiple benefits including building soil fertility and improving water resilience, to fostering better animal health and boosting biodiversity. Herbal leys are a traditional low-input method of farming that provides benefits to arable, livestock and horticultural operations alike.

Pollinators & Predators – July 3rd

How can we encourage pollinators and natural predators in order to reduce pests and increase production? Understand the role of these insects and learn ways to manage and maintain habitats for these unsung heroes.

Animals Into Arable Rotations – July 4th 

Are you thinking of introducing livestock back into your arable rotation? Join FarmED as
they explore the options and find practical solutions.

Sainfoin & Lucerne Field Day – July 5th 

Join the Cotswold Seeds team to learn about Sainfoin and Lucerne and how they
can benefit your farm

Wildflower Meadows & Margins – July 18th 

As well as looking appealing, wildflowers also have huge biodiversity and environmental benefits. Find out how to select and establish the seed mixtures that best suit your land.

Sort Out Your Soil – August 2nd 

We are joined by Anton Rosenfield from Garden Organic, and the Cotswold Seeds
team to show how green manures and cover crops can boost the fertility of your soil.

Self-Sufficient Leys Field Day – August 15th 

Learn how to use forage legumes to reduce reliance on nitrogen fertiliser.

Equine Grassland Management – September 12th 

Enhance you pasture management and increase species diversity to improve horse health and extend the grazing season.

Please book through  www.farm-ed.co.uk

Sign-up for their newsletter to keep up to date with what’s on at FarmED
Follow them @RealFarmED

Cotswold Seeds kindly sponsors our Soil Farmer of the Year Competition.

Farming sustainably- regenerative or agroecological?

A short blog written by FCT’s CEO Liz Bowles.

I was lucky enough to attend two events in May which got me thinking – the first being an afternoon seminar hosted by the Dutch Embassy in London and LEAF (Scaling up Regenerative Outcomes-tackling the challenges to mobilise change on May 3rd) and the second hosted by CiWF (Extinction or Regeneration on 11th-12th May). At both events there were distinct areas of commonality, mainly around how we produce food in the future, with livestock farmers involved with both events and key questions around how we need to produce food to respond positively to the climate and nature crises we are in.

A key driver for change amongst farming businesses requires a greater level of understanding of the impacts of regenerative or agroecological farming practices; a greater understanding of their financial impact and better mechanisms for monitoring the impact of changing farming practices on farmland biodiversity. At the moment without such evidence the case for change is not obvious to all and hinders action.

The future role of grazing livestock is another key area of debate, but increasingly there is acknowledgement that if we are to reduce our reliance on artificial fertilisers which lead to emissions of nitrous oxide then we need animal manures. Alongside that we know that grazing livestock provide for other wildlife to flourish on farms as well as consuming food that cannot be processed by humans (namely grass) and large parts of the UK are incapable of producing harvestable crops. Taking this together with the high quality of food produced by ruminants for humans (high quality protein and micronutrients) the case for grazing livestock is strong. Less strong is the case for intensive livestock production where those animals consume food which could be eaten by humans and where their production has negative impacts on farmland biodiversity and degrades soil. For the sake of human health we should reduce our overall consumption of meat products and where possible move to “better” products from extensive systems.

At both events it was clear that doing nothing is not an option.

Linked to the need to change how we produce food for the sake of all of us is the need to consider what future farming supply chains need to look like to support this revolution. It is not clear that we can make the changes we need to in production systems without changes to how supply chains work. At the moment it is those businesses buying from farmers who are leading on how they want farming practice to change, yes, to support a positive response to the climate and nature challenges we face, but, also to ensure that they can reach the self imposed targets they set themselves through such initiatives as the “Science Based Targets”.

Linked to this is the question – can we separate the food that farmers produce from the potential new income streams which farmers may be able to tap into such as the voluntary markets for carbon, biodiversity net gain and nutrient neutrality? In response to this a new farming cooperative has been formed called the Environmental Farmers Group. It brings farmers together to harness scale and member cooperation to secure the best environmental results and financial returns for a wide range of natural capital goods and services. This is the first such group in the UK and operates nationwide.

Alongside ensuring that farmers are properly rewarded for the changes in practice they make to increase biodiversity and store carbon, the key requirement for agriculture which is often being lost at the moment is how best for individual farm businesses to forge their own path to net zero. The first requirement is to know your baseline and one of the best ways to establish this is to use the Farm Carbon Calculator provided free to farmers by the Farm Carbon Toolkit. Once you have established your baseline you can start to look at all the opportunities to both reduce emissions and store more carbon on your farm. Farm Carbon Toolkit offers a comprehensive toolkit providing information on all the main ways to reduce emissions and showcases how farmers are already making changes and the benefits they are finding.

Contact us

If you would like more information for your business please contact info@farmcarbontoolkit.org.uk

Herbal Leys and Grassland Diversity

Written by Hannah Jones, a Farm Carbon and Soils Advisor here at FCT.

The farm environment is a complex for a plant.

Success of a sowing is controlled by an interaction between management, soil type, weather, pest and disease pressures as well as a legacy of weed burden. There is a plant for almost every environment on farm that can be used for successful production whether grazing, combining or for providing environmental benefits.

On grasslands with optimal pH, mineral indices and in a mythical situation of cheap inputs, ryegrass is ideal. If the farm environment becomes more challenging more plant species are needed to optimise that sward productivity.

White clover is a stalwart for improving crude protein content of a ration and increasing soil nitrogen supply but in dry free draining soils lucerne, and sainfoin may have much to offer. In a cutting ley, red clover and alsike clover have their merits, and if the ley is to be down for longer than 2-3 years birdsfoot trefoil is of value, particularly if sheep are involved.

Herbs added to the mix can support good mineral balance, improve weed suppressiveness, complementary anthelmintics to pharmaceutical wormers, and improve soil health. Chicory and plantain are common, but yarrow is good to include too for its drought tolerance and support of herd health. In open swards consider self heal, and in freer soils salad burnet.

Finally for those grasses, a diverse range of flowering times in the rye grass has value for grazing but not cutting. Tetraploid ryegrasses are impressive for silaging but longevity is surpassed by timothy grass. Cocksfoot has value in drier, more challenging environments, but careful management is essential to avoid clumpiness. Some of the fine fescues can support a denser canopy closer to the soil, particularly relevant for sheep grazing.

Plant diversity supports more resilient system, forage supply is better maintained under extreme conditions and the plant community in your fields will return from a climatic shock more rapidly.

Many farmers we have spoken to like herbal leys, why? Because they provide a more stable supply of forage, and the stock can get on the land earlier in the year and can graze for longer near the close of the year. This provides considerable savings in housing, and also reduces the need to buffer feed in periods of drought.

There is limited evidence across herbal leys, whether 3 species or 30 species that forage or silage quality is better or worse than rye grass and white clover. However, there is much anecdotal evidence that herd health is superior. Sheep seem to particular benefit from a diet of herbal leys.

These production efficiencies will improve your carbon footprint, but it is the effect of the diverse rooting systems of herbal leys that get us most excited. Herbal leys increase soil organic matter in excess of what is achievable with a ryegrass and white clover ley particular at sampling depths of 10-30cm. This additional carbon sequestration will again benefit your carbon footprint.

Finally, maintaining species diversity in herbal leys requires a paddock-style grazing system but I think that is for another day…

Methane Capture from Slurry

A Farm Net Zero (FNZ) event held in March 2023, Trenance.

Methane emissions from livestock make up a large part of a farm’s carbon footprint, capturing and processing these emissions can help to reduce the carbon footprint. Farm Net Zero Monitor Farmers, Katie and Kevin Hoare, milk 120 cows on a 130-acre Cornwall Council holding which required investment to improve slurry storage. They have worked with Cornish company Bennamann as part of a pilot with Cornwall Council to install a covered slurry lagoon that captures and processes methane gas for use as a fuel. A group of farmers met to learn more about the system, with talks from Dr. Chris Mann, co-founder of Bennamann, and George Mills, Area Sales Manager at New Holland who supply methane-powered tractors. This event was made possible with thanks to the National Lottery Community Fund who fund the Farm Net Zero project.

Chris Mann explained how the Bennamann system works, and how it can allow slurry pits to become mini power stations. Slurry is scraped into a reception pit where it is macerated to enhance breakdown and then into a well-insulated lagoon where microbial activity produces methane and other gases, as it does in an uncovered pit. The gases are collected by the cover, processed in a shipping container-sized plant unit with the cleaned methane pumped into another reception chamber sitting above the slurry pit. This processed methane can then be bottled and used as fuel in New Holland’s methane-powered tractor, or in a Bennamann methane-powered generator to provide electricity either for on-farm use or sold to the grid. 

George Mills showed the group around New Holland’s methane-powered tractor. Currently, this is able to do four hours of work on a single tank, with a range-extending fuel tank/front weight increasing this to twelve hours. Although slightly more expensive than a diesel tractor, the ability to run on home-produced gas can mean it is cheaper to run in the long-term by avoiding fluctuating fuel prices. Plus, the reduction in diesel use can have major benefits to reducing the farm’s carbon footprint.

Kevin and Katie say the covered and processed slurry is a better product to use as it is almost like digestate, allowing them to apply it with a trailing shoe between grazings and reduce the amount of artificial fertiliser they require. They are now able to meet all the grassland’s P and K needs from slurry, which has clear financial benefits and also helps their carbon footprint by reducing demand for carbon-intensive artificial fertiliser. A grass yield trial is in development to quantify the benefits of the new slurry.

The ultimate aim for Trenance is to go off-grid, with the methane capture system providing all the fuel for machinery and electricity. Katie and Kevin are keen advocates for agriculture’s role in providing climate change solutions and feel it is important for farmers to tell their story to the public to demonstrate their commitment to the environment. Using the Farm Carbon Calculator for Trenance through the Farm Net Zero project shows that the new slurry store is capturing around 600 tonnes of CO₂e from methane, putting the overall carbon footprint at 0.13 kg of CO₂e per kg Fat- and Protein-Corrected Milk (FPCM).

Key takeaways:

  • Methane capture from slurry reduces the farm’s carbon footprint by preventing methane entering the atmosphere
  • Using processed methane as fuel also reduces emissions from red diesel and electricity use
  • The methane capture system has financial benefits through reductions in fuel/electricity purchases, the option to sell gas and the ability to use slurry more effectively and replace bought-in fertiliser.

Farm Net Zero resources, events, newsletter

  • To find out more about other previous events, trials and resources produced from the Farm Net Zero project head here.
  • To keep an eye out for future Farm Net Zero events head to our events webpage here.
  • To keep up to date with the project subscribe to the Farm Net Zero newsletter here.

Hedges – a win-win!

A Farm Net Zero (FNZ) event held in February at Roger and Lavinia Halliday’s FNZ monitor farm.

Hedgerows are an important part of the UK’s agricultural landscape; they support wildlife, shelter  livestock and crops and capture carbon. To learn more about hedges and their multiple benefits, a group  of farmers and advisors met at Browda, Linkinhorne to hear how Roger and Lavinia Halliday manage  nearly 18 kilometres of hedge on their 250-acre organic suckler beef farm. This event was made possible with thanks to the National Lottery Community Fund who fund the Farm Net Zero project. 

Hedges at Browda are part of a Countryside Stewardship agreement with a BE3 “Management of  Hedgerows” annual payment and are laid on a 12-20 year rotation under the BN5 hedgerow-laying capital option. This work is completed by a hedge-laying contractor, with the stewardship payment covering their costs (but not the additional cost of clearing up, done by Roger, and any fence repairs).  Hedges are laid in the vernacular Cornish hedge style to create a thick, dense hedge. Any log wood cut  out of the hedge is then processed by Roger for fuel for the farmhouse biomass log boiler and the  remaining brash either burnt or tipped in a corner to rot down. This prompted a discussion on the  opportunities to make use of the brash with suggestions including chipping it for cattle bedding or garden  mulch. Dr. Rob Wolton, ecologist and chairman of the Devon Hedge Group, said that the brash creates an important habitat as it decomposes so it is useful to leave some. It is good to leave saplings to grow  into hedgerow trees for wildlife and livestock shelter. There are approximately 800 of these at Browda.  They need not be perfect specimens and dead trees are also valuable habitat. 

Dr. Wolton also spoke about the importance of managing hedges on a rotation to create a range of  habitats to boost biodiversity. Laying is the best way of achieving this, but flailing is also effective if done  sensitively, allowing the hedge to grow out a little more between successive flails and avoiding flailing at  the same level each year. This was an important reminder that the flail is just a tool, it can be used  poorly but can also be used well. Tree shears can be used to quickly and efficiently coppice hedges and  restart the management cycle, with the added advantage that trees can be lifted clear to avoid damage  to fences. Likewise, hedges can be layed mechanically, saving a great deal of manual work and time. 

Clockwise from top left: laid hedge and brash cut for processing, side flailed hedge, 5-year old regrowth on laid hedge.

Laying, incremental flailing and cutting on a rotation are all supported through both Countryside  Stewardship and the new Sustainable Farming Incentive Hedgerow Standards, along with coppicing,  filling in gaps and planting new hedgerows.

Roger and Lavinia have previously made use of grants for planting new hedges, shelterbelts and farm  woodlands, aiding the grazing management and creating wildlife corridors and refuges. Emma Eberhardt  from Cornwall Council’s Forest for Cornwall programme gave an overview of what they can support.  Forest for Cornwall aims to increase tree cover in Cornwall and can provide advice to landowners  looking to plant trees either as woodland or hedges, including fully funded planting support (free trees  and guards). Emma is involved in developing a network of agroforestry demonstration sites across  Cornwall to show how trees and agriculture can work together. 

Becky Willson from Farm Carbon Toolkit talked about the carbon benefits of hedgerows. At Browda, hedges are capturing nearly 86 tonnes of CO₂e every year and the hedgerow trees are capturing an  additional 40 tCO₂e, this is 43% of the farm’s total sequestration and offsets 24% of the farm’s emissions. Becky spoke about the new Hedgerow Carbon Code being developed as a route for private finance to pay for carbon stored in hedgerows. This is currently working on an estimate that carbon is  stored in hedges for around 10 years, so could fit well with a management rotation. However, it is still in development and not expected to be launched until later this year. 

Key takeaways: 

  • Hedges lock-up carbon as they grow, bushier hedges have more carbon than small hedges. 
  • It is important to maintain a diversity of hedge types to increase the range of available habitats. 
  • There are several grant options for hedge planting and management that are worth investigating.

This event was made possible with thanks to the National Lottery Community Fund who fund the Farm Net Zero project.

Farm Net Zero resources, events, newsletter

  • To find out more about other previous events, trials and resources produced from the Farm Net Zero project head here.
  • To keep an eye out for future Farm Net Zero events head to our events webpage here.
  • To keep up to date with the project subscribe to the Farm Net Zero newsletter here.

About the Farm Net Zero population wheat trial

Written by Hannah Jones, Research Manager at FCT, as part of the demo farm trials happening in our Farm Net Zero (FNZ) project.

Overview

Recommended cereal varieties are bred to look identical; the genes between individual plants have only minor levels of variation. The regulations around breeding and the sale of seed ensure consistency as well as ensuring different varieties are unique and suitable for the use (or group) stated.

Wheat, barley, and oats mainly self-pollinate which results in offspring being highly similar to the parent plant. Rye is a bit different; it is cross pollinated. Thus, a field of rye is in fact a population of rye where very plant is considerably different from its neighbour in terms of genes and sometimes in appearance.

Landraces

Seed that has been saved by communities of farmers within one particular region are called landraces. These landraces were locally adapted to specific conditions including soil type, local pests and diseases as well as management such as type of seed bed preparation. In landraces, since each plant is genetically different, the plants best suited to a given climate produced more seed. If the seed is saved and resown, the best adapted plants take up a greater proportion of the subsequent generation.

Evolutionary breeding

Over many generations, successive seed saving and resowing results in adaptation of a crop population, and thus this is called evolutionary breeding or population wheat (or barley). Evolutionary breeding can take place by default with landraces, or a population can be created.

Composite cross populations

The creation of a crop population involves cross pollinating a range of varieties that have interesting characteristics. This cross pollination needs to be done by a plant breeder. One such composite cross population was created from 20 varieties which had either good yielding or quality characteristics: the “YQ population” and was carried out by a team at The Organic Research Centre and John Innes Centre in early 2000 led by Martin Wolfe. The rules for selling grain have been designed according to the standard rules of uniformity of crop. Recent changes in regulations have now allowed the sale of population wheat if there is certified traceability.

Built-in resilience

The physical and genetic diversity within a population can increase the crop resilience to extremes in stress. Crop populations generally perform above the average of the original varieties. For example, if a particular race of a plant disease dominates in one year there will be some plants that have resistance; there will be some yield despite high disease pressure. Alternatively, deeper rooting will ensure under drought conditions there will be some plants that yield grain, whereas the shallow-rooters may be sterile.

Tim Williams (pictured below) at Erth Barton (one of our FNZ demo farmers) is trialling population wheat with his pasture cropping. The wheat has the potential to adapt to local conditions as well as being sown into an existing sward. To follow updates on our Farm Net Zero trials and hear more news, sign up to the FNZ newsletter here.

Tim Williams of Erth Barton Farm

Defra publishes its latest results on UK farm greenhouse gas emissions

Written by Liz Bowles, Farm Carbon Toolkit CEO.

Defra published its Agri-climate report last week. The report sets out the trends in agricultural Greenhouse Gas (GHG) Emissions over the past 30 years, the changing intensity of emissions and the results of the 2022 Farm Practice Survey questions relating to farmers intentions and actions on reducing GHG emissions.

The headline figure is that UK agriculture was responsible for 11% of total UK emissions in 2020. The time series is revised each year to take account of methodological improvements in the UK emissions inventory. It’s also worth noting that these are production-based emissions, rather than consumption-based which adjusts for trade.

During this 30-year period emissions of all greenhouse gases from agriculture have declined:

  • Total GHGs decreased by 16%
  • Nitrous oxide decreased by 20%
  • Methane decreased by 15%
  • Carbon dioxide decreased by 15%

However, it is important to note that most of this reduction occurred in the 2000’s, arising from a drop in ruminant numbers and less use of synthetic fertilisers. Since then reductions have all but stalled.

Some farmers are frustrated that the efforts they are making to reduce on farm emissions through practice change are yet to be recognised within the UK emissions inventory. This is due to the ability to accurately reflect the reductions through the current mechanisms for measurement, which are primarily measuring output versus inputs and livestock numbers and areas cultivated. This is changing as the quality of evidence on the impact of practice change becomes available.

In the meantime those same farmers are increasingly asking their suppliers for accurate emissions data on the products they buy, which is driving those suppliers to look far harder at the products they supply, which will in time lead to greater accuracy of measurement which is very welcome.

In the same report farmers were also asked their beliefs and motivations around reducing their GHG emissions. Interestingly, only 44% of farmers thought that reducing emissions would improve farm profitability in 2022, a decrease from 47% in 2021.

Of the 58% of respondents already taking action to reduce GHG emissions, the survey asked about their main motivations for doing so. This showed:

  • 84% considered it good business practice
  • 74% by a concern for the environment
  • 48% to improve profitability
  • 33% to meet regulations
  • 23% to meet market demands

It’s FCT’s experience that improving GHG emissions and sequestration on farms is good for business and good for the environment. We also experience that markets are increasingly incentivising action, such as increasing the accuracy of input use, improving input use efficiency and making much better use of legumes and clovers across the farm.

Farmers were also asked about the barriers to reducing on farm emissions. Here, there was a clear view that lack of information and incentive are significant barriers, even amongst those who have taken action, alongside being unsure exactly what they can do to reduce farm GHG emissions.

Factors preventing action to reduce GHG emissions.
Factors preventing action to reduce GHG emissions (Source: Farm Practices Survey 2022 – greenhouse gas mitigation practices)

At Farm Carbon Toolkit we can help farmers to better understand the actions they can take to reduce GHG emissions as well as providing free access to completing a farm carbon report for their farm business. We have developed a toolkit to assist farmers to identify the best GHG reduction strategies for their farms. For more information on our carbon calculator and to start your own farms report please see here.