Is regenerative farming the way to Net Zero?

“One season’s seeds, seven years of weeds” – is an old saying but well observed. The benefits of a soil-first strategy, to build up fertility and resilience of soils, is widely accepted but a full transition to regenerative farming still carries many unknowns, Rachel Holdsworth reports.

The last event of Agri-TechE Week 2024  was a meeting at Niab hosted by the Centre for High Carbon Capture Cropping (CHCx3) titled: “Can regenerative farming get us closer to Net Zero”. The need for monitoring and sensing technologies was stressed by many speakers and also a more objective evaluation of its merits.

Is Net Zero achievable?

Many regenerative farms are moving towards ‘Carbon Neutral’ where a balance is struck between emissions produced and carbon sequestered. However, Net Zero requires a further step, if emissions are not reduced then additional amounts of carbon need to be stored each season.

Work by FCT has demonstrated that raising soil organic matter levels by just 0.1% (e.g. 4.2% to 4.3%) per hectare can sequester approximately 8.9 tonnes of CO2e per year (at 1.4 g/cm3 bulk density). This is an extraordinary figure; in practice that is not only possible but being exceeded by farmers and growers building healthy soils.  However, as Liz Bowles CEO of Farm Carbon Toolkit explained, as soil health improves it will become saturated and reach a plateau where no further carbon will be absorbed.

Thus, the importance of creating a baseline so that the impact of interventions and rotations on the soil can be monitored and better understood, becomes vital to inform decision-making.

Soil is not the only channel for Net Zero, carbon can also be stored in perennial crops and emissions produced on farm, reduced by substituting fossil fuels used for agrochemicals and fuel for those from renewable sources.

The challenge for those wishing to monetarise carbon is where the tipping point comes, at what point does the carbon capture exceed the farm’s own production?

Liz commented that her preferred ambition would be to promote ‘farming for a positive climate outcome’ and to stress instead the benefits that can be achieved by regenerative farming – resilience to drought and floods, greater biodiversity, cleaner water.

Earlier adopters pioneering the way

There are many evangelical regenerative farmers, and Andrew Ferguson. General Manager of the Leckford Estate (John Lewis Partnership) is one. He described the ‘Farming for Nature’ programme which is supporting 150 of the farms that supply Waitrose with the knowledge needed to de-risk the transition.

The farm has introduced EMI scanning of the fields to determine variability and develop a baseline for monitoring interventions. Andrew stresses that definitive measurement is not possible but by being consistent – ensuring samples are taken at the same points in the same way – then relative change can be determined.

The major change over the last 5 years, has been to create a consistent rotation and process across the farm and develop a patchwork of fields that is good for wildlife year around. He has introduced companion cropping, new types of cash crops and enhanced diversity through poly cropping. His experiences and learning points are then shared by the group.

A cattleman at heart, a big concern had been the use of silage during the summer when water shortage killed the grass. He comments that a big improvement has been made by switch to herbal lays which provide green stuff well into summer and also a habitat for wildlife.

The farm also uses methane capture, harvesting sufficient gas from 450 cattle to fuel four tractors.

Andrew sees regenerative farming as a system – not a series of practices – as the value of the sum is greater than the parts. He gives the example of how healthy soils improve water retention quoting a difference of 6.5 tonnes per hectare yield of spring barley on unimproved soils, compared to 10.5 tonnes on those of the same soil type where regenerative practices had been introduced.

He stressed that accurate carbon data is crucial to quantify sequestration and that although SFI payments are generous that their approach made sense even without them. “We are better than carbon neutral, but not yet Net Zero as we haven’t reduced our emissions.”

Lastly, he referred to the behaviour-gap where consumers buying behaviour is different to their expressed intentions. “This is where Waitrose has stepped up to drive the industry forward.”

Will the city drive change?

Dr George Crane, Investment Manager for Yara Growth Ventures, which makes $25m investments each year into agri-tech and green hydrogen developments, was also cynical about consumer demand driving change.

He sees instead that the city is embracing climate finance and ESG reporting, and this is will in time reward companies that are respectful of the environment, resilient to climate change, and reducing emissions at a field or farm level.

Although agri-tech will be needed, he stressed that innovations need to have an intent that resonates with the value chain not just funding calls. “Someone must be prepared to pay for it so it must deliver value in productivity or profitability.”

He comments that publications have a bias towards positive outcomes of regenerative processes but that more objective assessments are needed to prevent unintended consequences. This is where MRC (monitoring, reporting, verification) technologies are needed to measure net value.

Going circular needs legislation to keep up

The circular economy could also provide multiple benefits, with Miha Piapan CSO of Better Origin explaining that food waste, not suitable for human consumption, has potential to be transformed by insects, such as black soldier flies, into a source of protein for animals and humans.

However, the legislation brought in after the ‘mad cow’ BSE outbreak has restricted this development. As insects are ‘farmed animals’ food waste is not a legal feed stock. Additionally, the costs of production are still too high for insect protein to compete with Soy as an animal feed.

He argued that the following measures are needed to accelerate growth of the insect economy:

• Policy over food waste needs to change – to enable growth and investment into the sector
• Greater access to scaling capital – agri-tech start-ups face a ‘second chasm’ to build the infrastructure required for pilots and to de-risk the technology – this has become harder to achieve over recent years.
• Incentives for ‘Net Zero’ such as carbon credits to become regulated to build confidence and drive adoption

Workshop – future direction

The workshop finished with an interaction session to capture the high calibre knowledge in the room.

The need to collate an evidence-base to support a move to regenerative farming was discussed further.

With warns that there is potential for unintended consequences including:

• Build-up of weed burden in soils
• Overwintering of pests in cover crops containing wild relatives of crop plants
• Introduction of alien plant species through bird mixtures and wildflower strips
• Build-up of soil pathogens such as wire worm
• Long-term consequences of direct drilling

The opportunity to change to novel crops, or older crop varieties that had fallen out of favour, was discussed with particular reference to:

• Legumes – Pulses, lentils, soy, sainfoin
• Fibres – hemp and flax
• Novel crops – cranberries and agro-floristry
• Perennial crops – such as kernza wheat

Niab has conducted a lot of research in this area and has identified which have greatest potential when taking into account the need for breeding to produce varieties of crop suitable for the UK climate, soils and cultivation and the need for knowledge of opportunities for market substitution and the infrastructure requirements.

Lastly, Dr Lydia Smith of Niab touched on the need to look beyond our shores and gain expertise from other geographic areas and the potential for pan-country value chains.

Further resources and knowledge will be shared on the knowledge hub, and she urged delegates to register ahead of its launch. www.carboncapturecropping.com

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