Back in 1967 my brother and I ran an organic macrobiotic restaurant and food store – we followed macrobiotics, the way of eating described in the book Zen Macrobiotics by Georges Ohsawa. The restaurant bought as much as possible from organic producers around London so we built strong links with the Soil Association, which was founded by Lady Eve Balfour in 1946. In order to talk about biochar I will first talk about soil, because that is the context into which biochar fits. Satish Kumar also spoke about soil last year in his excellent magazine Resurgence.
What is soil? Where did it come from? When life on earth began there was no soil, just rock. On and in that rock lived fungi that eked out a precarious living extracting carbon from the calcium carbonate of limestone. The atmosphere was mostly carbon dioxide and when it rained the rain became a weak carbonic acid solution that helped fungi to extract carbon from rock.
The rock slowly broke down to sand, silt and the finest particles – clay. But there was no ‘soil’, no humus, none of the decomposing plants, organic matter and living organisms that define soil.
Then a miracle happened
Tiny single celled organisms, ‘cyanobacteria’ (Latin for ‘blue bacteria’) developed the ability to take carbon dioxide and water and, with the help of sunshine, convert CO2 and H2O into simple carbohydrate: C6H12O6, or sugar. This was and is the fuel that powers all life on earth. The fungi saw their opportunity and locked the cyanobacteria into cells and strung them together in chain gangs.
Then they started to bundle them together in a form that we would recognise as plants
These strands of cyanobacteria became the earliest plants, such as horsetail
Plants were an efficient way to comb CO2 out of the air. The original plants didn’t even have roots, the fungi had their own root system inside the plant to extract the sugar as soon as it was made. The plants were the root extensions of the fungi, not the other way round, which is how it appears today. Plants evolved with root systems and the fungi continued to keep their root network in the plant’s root system. These fungi are called ‘vesicular arbuscular mycorrhizal fungi’ ‘Arbuscular’ means ‘tree-shaped’ and reflects the form they take when the occupy the root system of a plant. ‘Myco’ means ‘mushroom’ and ‘rhizzal’ comes from rhizome and means ‘root’ – so they are ‘tree-shaped root mushrooms’. ‘Vesicular’ refers to the vesicles that are the storage areas where the mycorrhizae hold a stock of nutrients and sugar.
A plant will deliver in its sap from 10-20% of the sugar it makes in its leaves to the mycorrhizae, retaining the rest for its own growth. The mycorrhizae increase the reach of the plant’s roots by up to 10 times, penetrating soil that plant roots can’t access.
The ‘arbuscular’ shape of the fungus is shown in a root cell – this tree-like shape is a mirror of a root system – the fungus has its roots in the plant, the plant has its roots in the soil.
There are other organisms in the soil that live symbiotically with the mycorrizae. Most notable are the actinomycetes bacteria – originally they were thought to be fungi because they copied the form of fungal hyphae, with filamentous threads. With the advent of electron microscopes they turned out to be bacteria that had strung themselves together in chains in order to efficiently ferry nutrients to the mycorrhizae in exchange for sugar. Most of our antibiotics come from soil bacteria. Streptomycin When a plant needs medicine, the mycorrhizae can farm it by feeding sugar to the bacteria that can produce that particular antidote – most commonly jasmonic acid, salicylic acid (aspirin) or ethylene. These medicines are sent up with the sap of the plant to provide it with immunity to fungal and insect attack.
One example of how mycorrhizae are used in farming is the French practice of ‘alley cropping’ where rows of fruit trees keep the fungal network going and enable crops planted in between to flourish rapidly thanks to the existing network of mycorrhizae supported by the trees. In Windsor Great Park an oak nursery accelerates the growth of oak saplings by raising them in ground surrounded by mature oaks – the big oaks provide the sugar to support a large mycorrhizal population. The baby oaks get sugar and nutrients from the mycorrhizae and grow away rapidly and healthily.
Soil is fascinating. It’s wonderful stuff. So what do humans do with it? Since the dawn of agriculture we mostly just kill it. Ploughing breaks up the neural network within the soil, though it reconnects fairly quickly but with a lot of casualties. Adding chemical fertilisers breaks up the symbiosis – the mycorrhizae no longer can exchange mineral nutrients for sugars because the farmers is providing them for free. The plant cuts off the sugar supply to the mycrorrhizae clustered around its roots and the mycorrhizae die off. Their 10,000 or so co-dependent microbial species also die off. The plant is then exposed to the challenge of fungi and other pests that give it nothing and just want to consume it. This creates the need for pesticides including fungicides, which further deplete the microbial population of the soil.
I have several generations of form in the area. My great great grandfather farmed virgin soil on the Koshkonong Prairie in 1842, cutting down trees and raising crops of grain and grazing cattle. My great grandfather farmed virgin prairie in Nebraska. These Norwegian farmers were notoriously stingy. They were frugal people in everything they did, they wasted nothing and recycled everything. Here’s an example:
My grandfather would deliver eggs from his chicken houses to the Safeway supermarket and other stores in Sioux City. He would then purchase tools, sugar, flour, salt, paper and other essentials that could not be produced on the farm. The flour sacks were made of calico, so the farmer’s wives would recycle the bags to make overalls for their boys and dresses for the girls.
Flour is a commodity – one bag of white dusty flour is just like the next. So the Nell Rose flour company marketing people got clever and printed nice floral patterns on their flour bags.
This appealed to people like my grandmother and she used Nell Rose flour to make the dresses for my mother (on the right) with her sister Thelma and their cousins.
This remarkable frugalism and avoidance of waste stands in stark contrast to the way that the soils of the Midwest were relentlessly wasted, often beyond recovery. Here there was no recycling, just relentless ploughing and harvesting, breaking down the soil. The farmer’s wives wasted nothing, their husbands wasted the fertile heritage of millennia. When land was ‘farmed out’ people would just move further west.
The original Louisiana Territory and adjacent territories embraced the great river network of the Mississippi, Ohio and Missouri Rivers, a 2000 mile wide water system draining into the Gulf of Mexico.
By 1925 more than 80% of the trees in this great river network had been cut down in order to create productive farmland.
The result was inevitable – the Mississippi Floods of 1927 were devastating – 27,000 square miles were inundated, up to depths of 30 feet. It triggered huge migrations of Afro-American farmers to Northern cities. Below Memphis Tennessee the Mississippi was 60 miles wide, 3 times the width of the Straits of Dover. The land was flooded from April to June.
This great flood was followed by further devastation. The weakened fractured soils of the prairie began to turn to dust and the winds blew up vast clouds of dust that reached as far as Washington DC, prompting Congressional action. President Roosevelt created the Civil Conservation Corps and 3 million recruits planted 10 billion trees from Mexico to Canada to try to hold down the soil.
This destruction of soil happened also in Argentina, Manchuria, Ukraine, and other fertile breadbaskets around the world as tractors and chemical fertilizer accelerated the rate of soil destruction.
The greenhouse gases carbon dioxide, nitrous oxide and methane that were emitted accounted for half of all the increase in greenhouse gas levels between 1850 and 1980. Since then agriculture’s annual rate of emissions has continued to grow, but has fallen behind the astronomic rate of emissions growth from manufacturing, energy and transport. But it is still responsible for at least one third of our excess emissions.
Total CO2 from Farming: 160 Billion Tonnes
Total CO2 from Fossil Fuels: 165 Billion Tonnes
How can we stop this wasteful and environmentally damaging activity?
Part of the answer lies in a discover that was made nearly 500 years ago. When the Spanish conquistador Francisco Pizzarro was buy looting the silver and gold of the Incas he heard about cities of gold with even greater wealth. He deputed his brother and Francisco de Orellana to find these cities and to bring back their gold.
The parties were separated and Orellana could not return up river. The chaplain on his boat kept records of their travels. They encountered wealthy populations but were repelled by armed natives, led by fierce women warriors. These natives knew already that if you came close to a white man you would break out in red spots of measles or smallpox and then, because they had no immunity, die. They attacked and drove them away – Orellana described his boat as looking like a porcupine after one such attack. They called this region the Land of the Amazons and this is how the river got its name. When explorers sailed up the Amazon about 30 years later the wealthy civilisations Orellana had described were gone – wiped out by disease. People questioned whether the ‘El Dorado’ he had described ever really existed.
Within the past 50 years archaeologists have found that the areas he described as populated coincide with areas where the soil is black to a depth of several metres – the ‘Terra Preta’ of the Amazon river settlements. Farmers who have Terra Preta have little need for fertilizer and even sell their soil to less fortunate farmers who are on the typical infertile jungle soils. The Terra Preta was made by the Amazons by taking all their waste, including animal bones and forest waste and domestic waste, piling it into pits, covering it with clay and setting fire to it. Once it was burning hot they’d cut off the supply of air and the material became charcoal and provided the growing medium for the next season’s crop. The contrast between Terra Preta and soils of the forest is apparent when the land is cut away.
Brazilian farmers who farm on Terra Preta benefit from its fertility and crops like corn grow vigorously when planted in black earth. They sell it to other farmers and bag it up for sale in garden centres. It is what we now call ‘Biochar’ – charcoal for use in the soil rather than charcoal for use for barbecuing sausages.
So what is Biochar? What does it do?
Biochar provides a supportive environment for mycorrhizae and their associated microorganisms. This leads to a doubling or more of the microbial population that is the living essence of soil.
Biochar had a high surface area – a single gram of biochar can have twice the surface area of 2 tennis courts – this means there are lots of points where minerals can stick, each point has a negative charge, so it sticks to minerals with a positive charge – this stops the leaching of nutrients from soil, keeping it in the zone where it can reach the plant.
Biochar also helps retain moisture. The result is healthier plants, more nutrient availability, more water availability and better soil structure.
Biochar also reduces soil emissions of nitrous oxide, a greenhouse gas 300 times more harmful than carbon dioxide.
Biochar stays in the soil, too, for anything from 10 years to 4000 years, depending on the type of biochar, the soil type and the farming system. The scientific consensus settles around 1000 years. This represents carbon dioxide that is kept out of the atmosphere – most woody biomass ends up returning to the atmosphere by rotting or being burned. Thus biochar can be an important tool for reducing atmospheric greenhouse gas levels. It is estimated that recycling woody waste as biochar could remove 1 billion tonnes of CO2 annually from the atmosphere. Instead we burn it.
Biochar retains the cell structure of the original feedstock. So biochar from bamboo has larger pores, biochar from chestnut has small pores. But all those pores provide a refuge for mycorrhizae and a base from which they can expand even if they are disturbed by ploughing or by predators such as mites, protozoa or nematodes that feed on them.
Imagine the pieces of biochar as a ‘five star hotel’ for mycorrhizae or, even as Norman castles in the English countryside. Each biochar particle is a base for a contingent of mycorrhizae, helping them to weather the stresses and pressures of life in the soil.
We have an image of mushrooms as passive softies but they are much more than that. When nematodes that threaten a plant enter mycorrhizal territory they get more than they bargained for. The mycorrhizae attach to them with sticky substances that hold them fast, then insert their filamentous hyphae into the tiny worm and suck out its amino acids, providing protein for more mycorrhizal growth and nitrogen for ‘their’ plants. Some mycorrhizae form lassoes that are scented with fragrances that attract nematodes – the nematode pokes through the lasso that then snaps tight, holding the nematode while it is digested.
Mycorrhizae also oversee the production of insecticides and fungicides. When there is a threatening insect or fungal pest the news travels fast through the underground internet – the mycelial network. The appropriate preventive medicine such as jasmonic acid, salicylic acid or ethylene is produced and delivered via the plant’s sap to the threatened area. How is this done? We don’t really know but it is likely that the mycorrhizae simply feed more sugar to the bacteria that produce these defensive chemicals and then pass them over to the plant.
It may be that the plant produces the defensive chemical itself or that it produces it in conjunction with the soil microbes. Both the plant and its supportive microbial community have a shared interest in defeating any disease threats quickly, before they have time to weaken the plant.
Biochar, by providing a resilient and abundant network of soil fungi and bacteria, is the framework of the plant’s immune system and helps it with nourishment and water.
So what have we done at Carbon Gold to turn this theoretical ideal situation into a reality?
The first thing we discovered was that the production method for charcoal was expensive, slow and inefficient – we wanted to reduce our carbon footprint in biochar production as much as possible and make it available cheaply to small farmers. We developed the Superchar 100 kiln.
It makes a 100 Kg batch of biochar in 8 hours instead of the usual 3 days. It delivers double the yield of traditional ring kilns. It has greatly reduced emissions – we recycle the gases emitted by the wood and burn them to heat the kiln contents instead of letting them escape into the atmosphere. They’re now hard at work in Belize, Botswana, Turkmenistan, Fiji, Brazil and the UK, with orders for more in the pipeline.
We also make a double-barrelled kiln that will produce 2 x 400 kg batches of biochar in a 12 hour day.
This one is part of a marshland regeneration project north of Perth, in Scotland
Whitmuir Organics, just south of Edinburgh, are making biochar for their horticultural operation and are experimenting with it in pig feed, where a small amount makes a big difference to pig health and feed conversion.
The first UK field trials of biochar were on my smallholding near Hastings in September 2010. We planted cabbages and winter lettuce in late September, some with biochar and some without. In November we had heavy snows and the lettuces were covered in snow for 3 days. When the snow melted the winter lettuces without biochar had died. Those with biochar were intact. I think this could be that a high microbiological population in the soil acts as underfloor central heating, biological activity generates heat and this is probably what saved the plants. We also discovered that biochar has no repellent effect on hungry pigeons, which destroyed the cabbage crop completely.
We work closely with Rijk Zwaan, the world’s 5th largest seed company and one that regards GMOs as an obsolete technology – they are world leaders at using natural breeding methods harnessed to genomic data. Their Field Trials Manager, Martin Kyte, stopped a comparative trial of Carbon Gold seed compost and peat compost after a few months because the results were so obviously in favour of our seed compost.
And Fergus Garrett, head gardener at the marvelous Great Dixter gardens in Sussex, has switched to biochar.
Stephanie Donaldson, Gardening Editor of Country Living magazine, trialled Carbon Gold with lettuces. After one month the difference was significant:
In Belize one of our shareholders took 3 Maya cacao farmers to Cornell University in 2008. We studied biochar production and its use with Johannes Lehmann, the world’s leading authority on biochar and founder of the International Biochar Initiative. After that we helped the farmers build a simple kiln. They did trials and found that cacao tree seedlings raised with biochar outperformed those without biochar in the nursery. A $50,000 UNDP grant helped them expand production and recently the Inter American Development Bank funded the establishment of 9 new nurseries with a target of producing 45, 000 cacao trees to really expand cacao production. It normally takes 6 or 7 years for a cacao tree to begin to produce, with biochar it starts in 3 years – that makes a huge economic difference to a farmer who has invested in establishing a cacao orchard.
Belize: Biochar + Cacao = fruit within 3 years
Normal maturation time: 6-7 years
We’re also working with farmers in Africa.
In Ghana, where tomatoes retail at $12 per kilo, Sunshine Organic Farms are starting to grow tomatoes near the capital, Accra. Biochar will help ensure healthy abundant cropping.
In Ivory Coast cashew nut waste will provide a feedstock that can then be used on cashew trees and in Senegal it will be rice husks that provide the feedstock.
We have just shipped a kiln to Botswana. Farmers in Fiji are now making biochar with our kilns to improve their fertility and cropping.
Wight Salads grow more than half of the organic tomatoes sold in the UK every year. They have greenhouses in Portugal and the Isle of Wight. Last year they started using biochar from us. The results: 8% higher yield, 10% higher sugar content in the fruit, less watering and fertilizer cost and, most excitingly, a dramatic fall in the population of root-eating nematodes. They had a lower level of this pest in their organic biochar production than in their conventional production where they use nematicide to kill this damaging pest.
They were considering cutting back on organic tomato production because of these nematodes, but now they are going to expand.
Some nematodes work collaboratively with mycorrhizae, some eat them, some just eat plants and some provide food for the mycorrhizae when they venture too close to the plant the mycorrhizae are protecting. Once lassoed they are soon converted into nitrogen compounds
Biochar works wonderfully on turf as well. Forest Green Rovers Football Club trialled Carbon Gold last year and found that at the end of the season this year the treated part of the pitch had withstood the stress of weekly games and practice far better than the rest of the pitch. Last week they spread biochar over the entire pitch and their groundsman has helped initiate trialy by the groundsman at Emirates Stadium, home of Arsenal. Those trials will open up new opportunities on sports grounds everywhere and help reduce the use of nitrates and other chemical treatments.
We make products for gardeners too. These are available from some garden centres, but most of our sales come from our own website, other online retailers, QVC and Amazon. This is because biochar still takes a bit of explaining and garden centre staff are not always available or able to tell a customer about it.
Last year we worked with Bartlett Tree Experts, the Queen’s tree surgeons, on trials with Carbon Gold biochar. They successfully cured honey fungus and saw accelerated growth in horse chestnut seedlings. The results of their research were published in April in the prestigious Arb Magazine, the journal for members of the Arboricultural Association. An ash dieback trial they initiated last year has so far shown no sign of infection, but they are waiting until this October before publishing any results. They have endorsed our tree growth enhancement and protection range and are now offering it to all their customers.
We are not yet capturing the carbon offset value of using biochar, but it is now becoming available as a carbon offset of value. The conversion ratios vary – our own figure is based on making biochar in a Carbon Gold kiln and reflects the greater efficiency and lower carbon footprint of the Superchar range of kilns.
In 2011 I visited the Green Party MEP Caroline Lucas in Brussels. She invited me back to present the biochar story to the Green Group of MEPs. In attendance were representatives from DG Agri and DG Enviro. They had a meeting after our meeting and the outcome was Eurochar. This programme funds research into biochar as a strategy for long term carbon sequestration and funds research into greenhouse gas mitigation with biochar.
Lady Eve Balfour lost the post war argument about the future direction of agriculture, but the Soil Association continued to fight the good fight while the introduction of subsidized nitrate fertilizer forced farmers into the industrial fold. The same process happened in the rest of the world and led to the Green Revolution, which is now running out of steam. Ten years ago there was a major collaboration to map out the future of agriculture in a world with diminishing resources and increasing population. WHO, FAO, UNDP, UNESCO, Defra, USDA, Monsanto and Syngenta were just a few of the global stakeholders who selected a crack team of 400 of the world’s leading agronomists to look at how we could reduce hunger, improve livelihoods and ensure social and environmental sustainability. 2 weeks before their report was published in 2009 both Monsanto and Syngenta went public by rubbishing its contents. Why? Because it said that the Green Revolution hadn’t delivered sustainable results, that genetic engineering was a dead end and that we should listen to small farmers and adopt traditional farming systems.
All of the other benefits of their proposals are summed up in rewarding farmers who prevent climate change. Whether you call it organic farming or agroecological farming, the fact is that farming in support of the living soil and its wonderful microbiological population is the only sustainable way to go. It is lower in carbon emissions and hugely effective in carbon sequestration. If only Lady Eve had lived to see this outcome that so firmly vindicated her predictions in The Living Soil published in 1943.
We are eating oil – it takes vast amounts of fossil fuel energy to make food energy and this is plainly unsustainable.
The Farming Systems Trial at the Rodale Institute in Pennsylvania has been growing the same crops side by side using organic methods and conventional methods. Once the health of the soil was restored, the organic crops matched conventional yields, showing greater resilience in years of drought. Every year the organic soil added 1 tonne of carbon to the soil, while the industrial crops gradually lost it. The organic crops used 45% less energy.
Professor Pimentel at Cornell University mapped it out: organic farming could reduce atmospheric CO2 by 1.1 trillion pounds a year. That’s half a billion tonnes of CO2 – about 1/10 of the annual increase in CO2 equivalent. Add in biochar and you would get at least another half a billion tonnes, bringing down CO2 levels by 20% a year.
If the cost of CO2 was factored into food production, then organic farming would deliver a € 350 per hectare cost benefit if carbon was priced at the real cost to future generations of €70 per tonne. Add in the benefit of €210 per hectare for every tonne of biochar added to the soil and agriculture could be part of the climate change solution instead of a major element of the problem. Lord Nicholas Stern quoted the figure of €70 per tonne in his book Blueprint for a Safer Future but a few months after it was published he said he was mistaken the real cost was €150 per tonne. Anyone who experience Hurricane Sandy in New York would probably agree. But even if CO2 was only priced at €35 per tonne it would deliver an economic imperative to farm organically and to use biochar universally. The Paris climate talks in 2015 will not exclude agriculture or transportation, the fatal mistake of the Kyoto protocols back in 1993. That will be when farming has to face reality and get a grip on its emissions.
And not a moment too soon. Every year 125 million hectares of land become so degraded they can no longer reliably produce crops. That’s nearly 2% of the world’s arable land. We have replaced that lost land by cutting down forests, but that is no longer an option. We have to live within the means of our natural capital of soil and that means not spending it but saving it and building on it.
Public health will benefit too. Antibiotics saved millions of lives – they were derived from soil bacteria. Now, due to overuse in agriculture they have created resilient disease pathogens that can no longer be treated effectively with antibiotics. 80% of all antibiotic use is in agriculture, to keep animals alive that could not survive in the filthy conditions in which they are raised, on beef feedlots where they wallow in their own excrement or in pig and chicken farms where antibiotics are the only thing that keeps the animals alive during their brief lifespan.
The sad thing is that industrial farming isn’t feeding the world. The world is feeding itself despite the waste and inefficiency of industrial farms.
70% of world’s food grown on farms smaller than 5 hectares
30% of the world’s food grown on industrial farms
$350 Billion yearly SUBSIDIES
No wonder the IAASTD was so adamant that small farmers using agroecological and traditional methods were the only way to feed the world. They can produce up to six times as much per hectare as industrial farms, using fewer fossil fuel-based inputs and more human labour. Our taxes are being wasted on subsidising the destruction of our soils and dangerous increases in greenhouse gas emissions from agriculture. Only a carbon tax can reverse this.
As this is a Slow Food Eire event it would be remiss of me not to touch on the similarities between the microbiological health of the soil and the microbiology of its counterpart in us, the gut flora, whose product is often referred to as ‘night soil.’ One third by weight of what we excrete is the offspring of the gut flora that have multiplied on our food in our digestive system and pass out along with the digested food. There are clear parallels in function between mycorrhizae and actinomycetes bacteria in the soil and the lactobacilli and bifidobacteria and associated microbial forms in the gut.
We know that babies born by C section are likely to lack the microbial flora that are part of a healthy immune system. It’s now established that stool transplants in patients with clostridium difficile can save lives – 110,000 Americans a year die of this infection, which arises after antibiotic use.
In the soil, worms are a sign of good health. The emerging medical treatment of helminthic therapy reflects the finding that the absence of worms in the human gut is associated with diminished immune function. When an earthworm consumes soil containing actinomycetes bacteria, an important part of the soil’s immune system that produces antibiotic substances, it excretes six times as many as it ingests. Roundworms in the human gut consume food we eat and excrete cytokine, an immune booster.
In Chinese tradition, Kwan Yin is the Goddess of Mercy and ‘mercy clay’ has saved millions from famine – it is rich in humus, minerals and microbial activity and can sustain a person when no other food is available.
In Haiti the production of clay cakes is commonplace. Made with clay, salt and oil, they aren’t consumed to keep hunger at bay, they nourish and have special benefits for pregnant women as it prevents morning sickness. Clay helps eliminate toxins and infections.
When one’s tummy is upset, particularly if traveling in foreign lands where a combination of different prevalent bacteria and different hygiene standards can lead to digestive disorders, charcoal tablets have the same beneficial effect on our digestive night soil as it does in the soil in which we grow our food.
I began this talk by quoting three people who have deeply influenced my thinking about soil and about its fundamental importance to our lives.
I would like to close by quoting an even higher authority:
“In the sweat of thy face shalt thou eat bread, till thou return unto the ground; for out of it wast thou taken: for dust thou art, and unto dust shalt thou return.”
The soil’s living community provides an example to our society of how a cooperative community of plants and microorganisms can maximise and efficiently share the production of food derived from the abundance of water, sunlight and carbon dioxide with which our planet is blessed. We come from the soil and we return to the soil, we owe all life on earth to the soil.
We should never treat it like dirt