Category: News

A Farm Net Zero event held at Ben Thomas’s monitor farm in Warleggan.

With fertiliser and feed rising in cost, many farmers are looking at how to grow grass and livestock with fewer inputs. A group of farmers gathered at one of the Farm Net Zero (FNZ) Monitor Farms to learn about rotational/mob-grazing from farmer Ben Thomas, and grazing consultant James Daniel of Precision Grazing Ltd. Ben Thomas farms 100 acres of species-rich permanent pasture in Warleggan, with 20 Belted Galloway finishing cattle moved daily in ⅓-acre plots. Winter stocking rate limits livestock numbers but Ben aims to reach 60-80 cattle. The landowner’s main aims are biodiversity, carbon sequestration and sustainable food production, and the rotational grazing system Ben employs allows for this, as well as fitting around Ben’s off-farm work as a farm manager. 

James Daniel provided an introduction to rotational grazing, including how to get started. James proposed that the main limiting factor to grassland productivity is infrastructure (fencing and water) and suggested that if farmers are planning to cut their fertiliser use, they would see the benefit of using some of their fertiliser budget on investing in infrastructure. James explained that the main principle of rotational grazing is not to graze recent re-growth; the roots on overgrazed plants will die off, reducing the speed of recovery and making pasture more susceptible to drought. Grazing should be at a speed that maintains vegetative growth, leaving leaf on the plants to maximise photosynthesis and subsequent re-growth. 

Key takeaways:

• Invest in infrastructure and start by splitting larger fields.
• “Wasted” grass can protect soil, regrow faster and potentially extend the grazing season
• Focusing on production from grass can reduce emissions from fuel, fertiliser and bought-in feed and improve soil carbon sequestration

Adopting rotational grazing can grow high-quality feed with fewer bought-in inputs. Fertiliser (and fuel to spread it) is a major contributor to a farm’s carbon footprint. If enough grass can be produced with less of these inputs then the farm will be closer to achieving Net Zero, as well as saving money. James referenced an Agri-Tech Cornwall funded study at Rothamsted Research North Wyke that found that rotational grazing increased the rate of soil organic matter (SOM) accumulation. If this is translated into soil carbon, then rotational grazing can help to capture carbon to offset the farm’s emissions. The same study also suggested that rotationally grazed plots had a lower weed burden, higher rates of available phosphorus and potassium and produced a higher liveweight gain per hectare than set-stocking. This suggests that rotational grazing can improve profitability by increasing production per unit of land and by keeping the soil and pasture in good condition.

Useful resources:

More information on Precision Grazing Ltd can be found here: https://precisiongrazing.com/ 

Preliminary results from the Agri-Tech Cornwall funded Cell Grazing research at Rothamsted Research North Wyke are available in a webinar here: https://www.youtube.com/watch?v=Hvu5Oj6ieYU 

What next?

Ben’s fields will be soil sampled and his farming operation carbon footprinted until the Farm Net Zero project ends in 2025. This monitoring will provide valuable information on the impact of rotational grazing both on soil carbon and the overall carbon footprint of the farm.

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

A Farm Net Zero event held in July 2022 at Campbell Hill.

Conservation grazing is a valuable tool for improving biodiversity in a variety of habitats. Farm Net Zero Monitor Farmer, Campbell Hill, has about 70 acres of clifftop grazing land on the edge of Looe as part of his tenancy. Here, he grazes Highland, Galloway and Whitebred Shorthorn suckler cattle. Calves produced from this enterprise are achieving a daily liveweight gain of 0.65-0.7kg/day and are then finished on the better grazing and silage of the main holding. A group of farmers and environmental advisors joined Campbell to discuss the options for effective management of the site. This event was made possible with thanks to the National Lottery Community Fund who fund the Farm Net Zero project.

Gerald Babcock, a farmer from West Penwith whose Whitebred Shorthorn cattle conservation graze 1500 acres for Cornwall Wildlife Trust and the National Trust, gave an insight into how his business works by making use of environmental payments. There are several conservation grazing options within Countryside Stewardship that Gerald makes use of, the main two are the Lowland Heath Management (£335/hectare) and Pedigree Native Breeds at Risk (£142/hectare) payments. 

Mike Ingram from the Farming and Wildlife Advisory Group explained that the way cattle graze produces a mosaic of habitats that supports flowering plants and provides refuge for insect life which in turn feeds birds and the wider food-web. Grazing also prevents the total encroachment of bracken, gorse and other scrub species; although these have a significant biodiversity value, a variety of habitats is best for a greater range of wildlife.

Key takeaways:

• Native suckler cattle on conservation grazing can produce a valuable calf cost-effectively
• Grazing is a useful tool for producing a variety of habitats, boosting biodiversity.

With changes to agricultural subsidy including a shift towards more environmental payments, there is the potential for conservation grazing to become a useful part of farm businesses. By providing farmers with a viable business option, conservation grazing protects important habitats which benefit wildlife but can also act as a carbon sink in plant biomass and soil carbon storage.

A FNZ event held in March at Andrew Brewers FNZ demo farm Ennis Barton.

Farmers, growers and advisors met at Demo Farm Ennis Barton near Fraddon to learn how Andrew has integrated vegetable production with his grass-based dairy. Depending on grass production, after six years, fields are rented out to Riviera Produce for cabbages. These are established using a strip-till machine to minimise soil disturbance. Following harvest, any leftover cabbages are grazed by Andrew’s youngstock, before going into spring barley or a grass ley. Andrew is particularly keen on grazing the vegetable residue, as it makes the material “more palatable to the underground livestock” and provides valuable grazing. We also heard from James Wimpress of the Environment Agency, on how to reduce the risk of soil loss from vegetable fields – an important consideration as soil erosion releases carbon as well as removing a valuable asset. Jan Dinsdale from Cornwall Wildlife Trust spoke about the Environmental Land Management Scheme (ELMS) Test and Trial. This event was made possible with thanks to the National Lottery Community Fund who fund the Farm Net Zero project.

Key takeaways:

• Fields for vegetable production should be selected carefully – flattish, with minimal erosion risk.  
• ELMS is more targeted than previous subsidies but can cover some costs for important soil tests.
• Integrating livestock and vegetables can reduce bought-in feed requirements.

Growing field vegetables can be an important income stream and break crop, as well as contributing to the nation’s self-sufficiency. However, they can also damage the soil if not grown sensitively. Methods of growing field vegetables in a rotation with grass and cover crops can help to mitigate any soil erosion and improve the rate of soil health recovery and soil carbon capture.

What next?

Andrew’s vegetable fields will now go into either spring barley, grass leys or cover crops and will be assessed to determine which option can restore soil health and capture carbon the fastest. An earlier FNZ cover crop trial on Andrew’s farm, plus Blable (Demo Farm) and Tregooden (Monitor Farm), showed encouraging results for diverse cover crops and their impact on soil health. The trial results can be seen here.