How topping up manure with biochar has improved soil health

When prices of manufactured fertiliser and cattle concentrates increase, Mick and Sandy Jones do not see the financial impact in their suckler beef enterprise.

For 15 years, they have grown grass, herbal leys and lucerne on their 40ha (99-acre) farm near Welshpool, using no inputs of purchased fertiliser.

These feeds have been the sole source of nutrition for their 30-cow suckler herd.

See also: Video: Soil health focus reduces cow variable costs by 40%

Soil nutrients are topped up with applications of farmyard manure (FYM) and, since 2019, biochar, a type of charcoal.

The biochar is produced on their farm, Caebardd, where the Joneses also run an engineering business with their three children – Stuart, Kim and Darren – specialising in the manufacture of renewable energy equipment.

Farm facts

Caebardd, Welshpool

Mick and Sandy Jones © Debbie James

• Calving from December to March
• Calves weaned in October
• Cattle sold as stores at Welshpool market spring sales at 14-16 months or finished and sold to ABP at 18-24 months
• Marginal land
• 940mm average annual rainfall

Accidental discovery

The first batch of biochar was the result of a “happy accident”, generated when a rotary biochar combustion grate the business was developing experienced a fault with a fan, says Mick, the third generation to farm at Caebardd.

He applied the resulting 10t of biochar after first-cut silage and incorporated it with cattle bedding to absorb urea and prevent its conversion to ammonia.

As a result, he has seen big improvements in both the capacity of the land to grow grass and clover and in cattle health.

With just one annual application of biochar-enriched FYM, the farm now routinely produces four cuts of silage instead of three, and with bigger yields.

Mick puts this down to improved soil health, an observation backed up in a recent soil analysis by Farmacy.

© Debbie James

Improved soil health

In the past four years, soil pH has risen from 6.6 to 7.1, organic carbon by an annual average of 0.48%, and available phosphate by 66%, to 219kg/ha.

“Total exchange capacity [TEC] has increased by 68%, which goes a long way to explain the increase in fertility and symbiotic exchange,” explains Mick.

The analysis report describes the increase in the organic carbon level in four years, from 5.28% to 7.10%, as at the “high end of regenerative systems and consistent with biochar-enhanced practices” and reflecting “real gains in soil structure, water-holding and biological life”.

The boron level is at its optimum, calcium has exceeded targets without external amendments, and a decrease in the level of magnesium to 16.05% (the farm is targeting 12%) has improved soil structure and reduced the risk of compaction and poor drainage.

Benefits for clover

All this in combination is a good environment for clover production which, by fixing nitrogen in the soil, encourages grass growth.

“Since we applied the biochar, the clover starts growing a month earlier in the spring and a month later in the autumn, and it is more resilient through the winter,” says Mick.

Mick has completed soil biology researcher Dr Elaine Ingham’s Soil Food Web School foundation course.

The increase in clover growth has been achieved despite some very challenging growing seasons, including drought conditions in 2022 and an exceptionally wet winter in 2023-24.

Although he does not have data to support it, he reckons yields are on a par with what he might expect to achieve if synthetic fertiliser was applied.

No leaching

“Biochar has helped us maintain soil health and productivity without needing to return to synthetic inputs,” he says.

“Once you get the soil microbes working properly, the soil chemistry will find its own balance.

“Farmers aren’t realising anything like the full potential within their FYM – biochar gives us that ability.

“Perhaps the most understated but important benefit is that nutrient run-off and leaching have been virtually eliminated,” he adds.

Benefits to cattle health

The farm supports a suckler cow herd of mixed breeds including British Blue-crosses and the more recent addition of the Murray Grey.

Biochar is mixed with “tree fines”, which is similar to sawdust and produced on the farm as bedding for the cattle during winter housing.

That inclusion lowers ammonia production in the soiled bedding, soaking up urine and creating an inhospitable environment for “bad” bacteria.

Bedding remains aerobic, encouraging healthy microbes and deterring pathogens – and that is beneficial to cattle health.

“Calf scour is now almost non-existent, and when it does occur, it’s far less severe.

“It’s made a huge difference to calf health and early development,” says Sandy, who is responsible for calving and managing the herd.

In the past four years, the farm’s veterinary costs have at least halved.

“It’s a reflection of how much healthier and more resilient the animals have become,” says Sandy.

“The maximum dose of antibiotics any calf received in this calving period was 2ml.”

When the bedding is applied to the land, the benefits continue, Mick adds.

“When the manure goes onto the land, it has the right aerobic bacteria, and the nitrogen is released as ammonium, not ammonia, which the soil can use without losing 65% of it to the atmosphere or leaching.

© Debbie James

“Biochar captures nitrogen from manure in a stable, non-leaching form, which is only released slowly by aerobic, mineralising bacteria in the soil.

“This avoids the ‘nitrogen-shock’ effect seen with synthetic fertilisers, and supports stronger symbiosis with clover and legumes, increasing natural nitrogen fixation throughout the growing season.”

No concentrates have been fed for about 20 years – the herd is grass-fed during the grazing season and is on a diet of haylage during winter housing.

Cattle are visibly healthier, says Darren.

“Even through the winter months, they’ve been noticeably more lively, showing the same energy and alertness you’d usually only see when they’re first turned out onto fresh spring grass.

“It’s a clear sign that overall health, energy levels, and nutritional balance have all improved.”

Progeny are finished on haylage only. “Typically, we are seeing weight gains of 1.2-1.3kg/day from calving weight,” says Mick.

Cost

At about £750/t dry weight, biochar is not a cheap alternative to synthetic fertiliser, but its inclusion rate with FYM is only about 5-10%.

The Joneses are currently exploring the option of creating biochar from de-watered slurry combined with a small percentage of wood.

“If produced on-farm from either de-watered slurry or digestate, then the cost would be nearer £200/t, as it still attracts the full carbon value in production,” Mick calculates.

Biochar use at Caebardd works out at about £6,000/year.

“But we have no feed, fertiliser or lime bills, and it is easy to keep the leys in production longer between reseeds,” he points out.

For the Joneses, regenerative farming has created a system that they describe as “more balanced, more relaxed, and genuinely stress-free farming – resilient and in tune with nature”.

“We now see soil not as something to be managed, but as something to be supported and nurtured,” says Mick.

“When you look after the life in the soil, everything else falls into place.”