Healing the earth

Soil is the second largest carbon store after the oceans, but it’s being degraded at an alarming rate. One farming community is pioneering a soil health project to show how organic regenerative agriculture can restore this vital ecosystem with benefits for biodiversity, climate and food.

Beneath our feet lies one of the most complex ecosystems on Earth. Teeming with microbes, fungi, earthworms, insects and the extensive root systems of plants, soil is estimated to be home to more than half of the planet’s biodiversity. It holds nearly 80% of the total carbon found in terrestrial ecosystems – but it’s in trouble.

Thanks to deforestation, intensive agriculture, urbanisation and pollution, around a third of the world’s soil is degraded. Experts predict this could increase to 90% by 2050, with potentially catastrophic consequences  or food production, the environment and climate change. Not to mention worms.

Some farmers are well aware of what’s at stake – and are taking action.

Soil health, and its associated benefits, has long been something of an obsession at Yeo Valley Organic. he dairy brand, which sources its milk from 100 farms in the south and west of England, first sampled the soil on 162 hectares (400 acres) of its own land in 2015. It followed up with a major project to test the soil at 25 of its supplier farms. Sampling more than  6,070 hectares (15,000 acres), it tested for nutrients, pH, organic matter and carbon. It also analysed the soil’s structure and counted the number of worms, a key indicator of soil health.

“That gave us loads of encouraging indicators – including 23,833 worms – about different farming practices, but it also said that we need to go bigger, we need to go further, we need to  go longer term,” says Tom White, regenerative farming manager at Yeo Valley Organic.

The brand is now rolling out soil testing across all of its suppliers, with repeat sampling taken at five-yearly intervals. The idea is to create a rich and rigorous data set on which to base decisions around crop rotations, grazing schedules and more.

Yeo Valley Organic practises what’s known as regenerative agriculture, a holistic farming method where food is produced under a set of principles that prioritise nature recovery. By minimising disturbance to the soil, protecting it with cover crops, keeping living roots in the soil, cultivating a wide range of species and using grazing animals to feed the soil with their manure, soil resilience is boosted. And so arise all kinds of benefits, from biodiversity to improved water quality, and from higher rates of carbon sequestration to flood  mitigation.

More and more UK farmers are seeking to understand how their land could benefit from regenerative agriculture, says Liz Bowles, chief executive of Farm Carbon Toolkit, a social enterprise that supports farmers to produce food within climate and nature-positive systems.

“Our climate is going to change more … and it will become critical that we as farmers look after the ecosystems that we rely on – soil, water, air and habitat.”

That thinking resounds with Sophie Alexander, a supplier of milk to Yeo Valley Organic, who oversees 1,200 acres of arable land at Hemsworth Farm in Dorset, and is working with the brand on soil testing. “There is a responsibility that can’t be ignored: to try to find out what best practice is,” she says. “The temptation is to oversimplify, but it’s so complex: you’re dealing with life in all its permutations. The same technique does not suit every farm, it does not suit every soil.

“Because we use a variety of legumes and grasses, with differing rooting systems and growing rates, the diversity means that [whatever the conditions, there will be] something  resilient enough to survive,” she explains. “It really is a whole-farm system.”

It’s a decade in for Yeo Valley Organic’s soil testing work and results are promising: organic farming with regenerative principles is doing what it says on the tin. Despite the driest spring the UK has seen in 132 years, there was grazing available for Alexander’s cows right through the summer.

“Change in agriculture is quite slow,” says White. “What started as some bags of soil on our own farm has now become a huge piece of work. Cattle are amazing bioreactors – when it rains, microbes literally drip off their backs. Everywhere they go, they spread this life, and it’s the same life that’s in the soil.”