Tag: livestock

Your beef enterprise: how to accurately estimate emissions and sequestration

To accurately estimate the emissions and sequestration from your beef enterprise, you will need to add data to the following sections of the Calculator:

  • When setting up the report, make sure you enter the area of grazing (grassland) as well as any non-agricultural land area and cultivated land (arable or horticultural)
  • Use the Livestock section and select beef cattle. Add as many entries as you need to cover your herd. For example, you may have two groups of steers with different liveweights or kept on the farm for different lengths of time. In which case, enter the steers from the first group with one liveweight and then the steers from the second group as a separate entry with their own liveweight. This will give you more accurate emissions from their enteric fermentation (gut methane).
  • To calculate the average head of livestock on the farm over a 12 month period, take the number in a particular livestock category per month (so you have 12 “snapshots”) add these together and then divide by 12. Our data collection sheet has a help sheet for this. For growing animals, you may want to use the same approach for calculating average liveweight (our defaults assume a midpoint liveweight through the year for growing cattle but growth rates won’t be linear so using the snapshot approach may be more accurate)
  • Livestock entries also capture the CO2 equivalent (CO2e) of the methane emissions from enteric fermentation and of the nitrous oxide (N2O) emissions from the animals’ manure over the course of the year. The Calculator asks you how this manure is managed as this has an impact on the N2O emissions
  • You have the option to input the average dry matter intake (DMI) per animal per day (kgDM/head/day). The DMI can be used to more accurately calculate the enteric emissions of the cattle, and if left blank, a simpler algorithm will be used that does not consider DMI
  • You will need to account for any supplemental feeding via the Livestock > Animal feeds option – this is for brought-in feeds that were produced off-farm
  • Account for all your fuel use, electricity use, consumables, inventory items and waste produced using the relevant sections (Fuels, Materials,  Inventory, Waste). However, if you also have a dairy herd or arable operation, you may prefer to create a separate report and use this as an Overheads report to apportion shared capital items and energy usage emissions between your enterprises. Watch our video to see how this works in practice.
  • We recommend getting your soil sampled and have a guide on how to do this effectively and affordably. By monitoring your soil organic matter or soil organic carbon over time you can begin to log sequestration rates in your grazed (or other) soils. Once you have two years’ worth of soil sample results, you can enter these in the Calculator under Sequestration > Soil Organic Matter (you will also need bulk density measurements and a record of the depth of the sample).
  • If you don’t have directly sampled soil data for all your soils, you can use our range of proxy values for different Countryside Stewardship and habitat classes to estimate how much carbon your soils may be sequestering year-on-year. You can also measure the length of any hedgerows and field margins (ungrazed) and enter these to estimate the carbon sequestered in them on a yearly basis.

The Financial Reward of Reducing Carbon

By Robert Purdew, Farm Carbon and Soils Advisor

There is a growing concern about carbon “tunnel vision” in agriculture, where the sole focus is on reducing emissions without considering the bigger picture. Reducing emissions is crucial, yet it’s important to acknowledge that it is only one piece of the puzzle and focusing solely on carbon can neglect factors such as soil health, water quality, biodiversity and other issues such as pollution. There is also often concern from farmers about how the pressures to achieve net zero targets can impact profitability, especially when incentives to be net zero are limited or non-existent, and investments in the infrastructure and technology required to transition to low-carbon farming are high.

But this doesn’t have to be the case. We can use an understanding of a farm’s emissions to make informed decisions to change management practices that can lead directly to both reduced emissions and increased profitability, and we can point to an increased number of farmers who are doing just this.

Mike and Sam Roberts farm 435 acres at Blable Farm, of which a large proportion is down to herbal leys. After Sam returned to the farm in 2018 a decision was made to review the whole operation and, in conjunction with James Daniel of Precision Grazing, the decision was made to reduce the herd slightly from 180 to 150 cows, implement rotational grazing on diverse leys and to focus on reducing inputs and improving soil health.

Cattle out wintering at Blable Farm

The effects were immediate and obvious. Soil health has seen a rapid improvement with better structure, increased earthworm numbers and soil organic matter is on the rise. The grazing period has been increased from 6 to 12 months and the farm hasn’t bought fertiliser since 2021, with none being used last year. Importantly, animal performance has increased in line with improved soil health and while cow numbers were reduced initially Mike and Sam are looking at increasing numbers again. All of this has seen a significant saving on input costs which has been re-invested into the business, including a full soil audit to better understand how soil health is improving. In line with reduced costs on-farm emissions have been reduced significantly with Mike confident the farm can reach net zero within 5 years, a commitment made as part of being a demo farm for the Farm Net Zero project.

Another example of a farmer using an understanding of their carbon footprint to drive down costs and improve profitability is Tom Burge of Oaremead Farm. Tom farms 760 acres of grassland on Exmoor and runs both a suckler herd and commercial sheep flock. In 2017 Tom began shifting to a more regenerative farming system which predominantly focussed on an improvement in grazing management, once again aided by James Daniel from Precision Grazing.

A person standing in a grassy field with cows

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Over 5 years, Tom has completely cut out the use of artificial fertiliser and reduced his feed use by over 70%. This has been made possible by an increase in dry matter grown of 0.9 tDM/ha, through improved grazing management, and has reduced input costs by 50%, with a similar reduction in emissions from inputs, as shown in the chart below. Crucially the farm is now profitable before taking into account income from subsidies and environmental schemes. In the next 5 years, Tom plans to completely cut out bought-in feed and to have halved fuel use and, like Mike and Sam, be well on the road to net zero while remaining highly productive and profitable.

Oaremead Farm emissions from inputs

These are just two of an increasing number of examples that we are coming across as we work with more and more farmers who are using their carbon emissions as just one metric to help improve their farm businesses. And far from impacting just a farm’s emissions and bottom line, the management changes that are being implemented are having beneficial impacts on those ecosystem services mentioned previously, soil health, biodiversity, water quality and reduced pollution. Proof if ever it was needed of the potential for long-term sustainability within our farming systems.

The complexities of calculating livestock emissions

What do we mean by livestock emissions?

Emissions from livestock cover two broad categories:

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

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

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

Why do the emissions associated with livestock vary?

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

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

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

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

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

Livestock and Trees with Lindsay Whistance

Wednesday 27th September 2023

Farm Net Zero was pleased to host Dr. Lindsay Whistance from the Organic Research Centre. Lindsay specialises in animal behaviour and welfare and her talk presented results from a range of research studies on animals in agroforestry systems. This event was made possible with thanks to the National Lottery Community Fund who fund the Farm Net Zero project.

The talk was hosted by Demo Farmers, Mike and Sam Roberts, at Blable, Wadebridge. Mike and Sam spoke about the different motivations for tree planting, with Mike being interested in trees with a useful end value (having experience of growing a small fir plantation on the farm) and Sam wanting to learn more about the benefits that trees can provide to cattle daily liveweight gain in their rotational grazing system.

Firstly, Lindsay explained that good welfare is about maintaining homeostatic equilibrium – or balance, both physiological and emotional. Most of an animal’s daily behaviour is about trying to maintain that balance, and farming should aim to support this wherever possible.

Lindsay spoke about three main themes of animal behaviour and welfare in agroforestry systems. The first was temperature regulation; if animals are too hot or too cold, then they will spend energy on trying to reach a balance. Where there is access to trees, animals are able to reach that balance faster as the trees provide shade and shelter from wind and rain. This is particularly important as climate change brings greater extremes of weather.

The second theme was the feed value of browsing on trees. Leaves on a number of tree species have been analysed and found to contain high levels of micronutrients and trace elements. This can provide additional benefits to the animal’s diet.

Finally, Lindsay spoke about the calming effect trees have. There is evidence that animals in woodland have better social relationships with less fear and aggression.

Overall, if livestock are in good welfare then they are able to use energy for fulfilling their potential. This improves efficiency of livestock production, which has benefits economically and for the farm’s carbon footprint.

Key takeaways:

  • Most livestock species benefit from access to trees/woodland.
  • Incorporating trees into farming systems helps to reduce the carbon footprint.