This article has been written by Elaine Watson for QE as a result of the chilling remark with which Dr Lynne Boddy, Professor of Microbial Biology at Cardiff University ended her talk on the “Hidden Kingdom of the Soil”. Having described how miles of fungal mycelium link plants and trees in a network essential for life; she warned that if we continue with current methods of farming, we have “only 100 harvests left”!
Elaine studied Zoology at the University of St Andrews (BSc Hons); soil microbiology at The Macaulay Institute for Soil research and Aberdeen University (MSc); worked as a research assistant in the Applied Biology Department at Cambridge University on plant pathogens; and teaches medical science to students of homeopathy all over the world. She sits on Quantock Eco’s Executive Committee in an ex-officio capacity representing Forum 21.
A title such as this does not offer much solace while we are incarcerated because Corona virus snuck in and changed everything for ever. The Kingdom Protista could have finally trumped all of mankind saving us the inconvenience of taking further action to save the planet from humans. But instead of totally annihilating us (which it could have done) Covid-19 has given us a generous ‘get out of jail’ card. Ironically we are currently the ones in the cage while Nature is free and frolicking.
So it is vital now for us to grab that card and run with it, making essential changes to everything while we can, in order to allow Nature to recover from the ravages of mankind’s activities. We have been given a golden opportunity. While we are all passionate eco-activists it is clear from the potent newspaper headlines that many people have awoken from their opium-like slumbers and noticed that the countryside in springtime is actually very lovely. Hurrah!
Unless you are currently too young to be able to read, you are unlikely to be around to know whether we were right in our apocalyptic message that there are only one hundred harvests left. The date inscribed in stone is 2050 for us to get our act together to protect the environment, but it needs to be much earlier than that. Certainly we owe it to the following generations to rectify everythingso that they can have a happy co-existence with the natural world.
The forecast is definitely gloomy yet I think there is still the possibility of remediation; but only if we take immediate action. Surely by now we are all super-saturated with the facts, figures, statistics and graphs showing the exponential rise towards our inevitable extinction?
We have been observing the above-ground apocalypse and the marine environment choking with plastic residues, pollution and micro-particles. Rising temperatures, melting icebergs, isolated polar bears, holes in the ozone layer, forest fires, orangutans left clinging to single tree trunks, floods , polluted air, pollinators decimated are all tangible evidence of ecocide.
Even as we enjoy the bird song, the clear blue skies, the scintillating night skies with a super moon and meteor showers, the CO2 levels are still rising and atmospheric ionic composition is changing invisibly for the worse. Maybe we as citizens can’t do as much as we would like about that but we can do something about improving things at grass roots level – literally.
The soil is actually our most fundamental Earth-borne gift and we now have an opportunity to nurture it and return it to health. Lockdown has forced us into thinking local rather than global (which is a good thing in many ways) in order to survive. No longer can we race around buying epicurean fancies from around the world and maybe in future we will think twice about where things come from and whether we really need them.
In Somerset we have access to some of the least polluted produce in the UK. Wouldn’t it be wonderful if we could reverse the trend for industrialised chemical-reliant farming and horticulture and encourage and support low-impact, highly sustainable methods? The soils would be healthier, the air, the waterways, the vegetation and the marine environment would be healthier, and we would be much healthier too. Win-win!
So what can happen at grass roots? It is almost a derogatory term to say ‘let’s go back to grass roots’ but this is absolutely where we need to be right now and where there is the greatest possibility of remediation to be done by the masses for the masses. There are lots of easy things we can do. This is not rocket science. All we need to do is tap into our birth-given intuition and work from our instincts.
The roots of grass grow very well almost all over the Earth- in the soil. The land mass of our planet is covered in soil of some sort. So why don’t we care for it and nurture it? Maybe we thought we were when after WWII our farmers were encouraged out of traditional agriculture into chemical agriculture and paid vast bonuses for producing yields the size of which had never been seen before. It wasn’t a malevolent act- it was essential to increase food production. Sadly, that calamitous dash for intensification put three quarters of farmers out of business and had a massive impact on the rural landscape. But if you love something or someone you wouldn’t intentionally poison them would you, and clearly- very clearly, the agrochemical revolution has meant that some of the most toxic and persistent toxins known to man (and pollinators, insects and weeds!) are entering food chains. Fortunately, hidden below the surface of the land and largely invisible to the naked eye there is an elaborate community which may be our life line.
Our most precious resource is not just ‘dirt’. It consists of an intricate, mineralised environment harmoniously maintained by micro-organisms and buzzing with life. Not only is it rich in inorganic minerals, it is home to more species of microscopic organisms than the whole Plant Kingdom together. Professor Lynne Boddy recently gave QE the most fascinating and informative talk about soil fungi, their mycelial networks and life-sustaining mycorrhizal relationships with plants.
Fungi are the principal decomposers in ecological systems and mycorrhizal fungi have waited a long time to be in the lime light and for people to wake up to how important they are in making and retaining resilient, dynamic soils. These invisible organisms interconnect with all subterranean life to supply essential organic nutrients, and also maintain and manage the architecture of our soils.
They associate with approximately 95% of the plants on Earth and they sequester carbon in much more effective ways than our attempts at carbon-offsetting could ever achieve. They provide a boost to the immune function of plants and by their community-wide actions support the plants in their environment. There is a subtle exchange of nutrients between fungi and plant roots which enhances the nutrient profiles of many plants, which if they happen to be crop plants means their nutrient profile for our consumption is also improved.
However, dolloping generous helpings of NPK fertilisers repeatedly onto our agricultural soils can lead to catastrophic decimation of these fungi and contamination of the waterways. Phosphorus in particular, knocks soil fungi straight out of play.
We can now appreciate that careful crop rotation, application of the natural fertilisers produced in mixed farming regimes, as well as nurturing flower-rich pastures, allow the subterranean communities to flourish with the additional bonus of providing healthy yields.
When traditional farming methods fell apart after WWII with the introduction of the Common Agricultural Policy (CAP), and incentives, profits and massive yields became the norm, large-scale mechanisation of farming practises occurred and grubbing up hedgerows and field boundaries became essential. Ancient ecosystems were removed at a stroke and soil erosion occurred when the wind blew and the rains came.
Excessive mountains of oil seed rape and butter as well as wine and milk lakes were unquestioned results of the new farming policies and encouraged more and more use of agrochemicals on rapidly depleting soils. No one really noticed at the time that food was becoming insipid and cattle and other livestock were becoming increasingly susceptible to disease. The pharmaceutical industry certainly boomed as natural ecosystems were driven out of synch to the inevitable point of collapse. All may not be lost!
Soils can be robust, fungi can adapt and we can wake up! The most important thing is that we don’t leave it until it is too late! If we all tried to buy local, fair traded, organic, or free range produce from a known source, that would give a massive incentive to farmers to return to less-expensive, traditional farming methods and allow the soil to recover. There is no doubt that traditional pasture-fed beef tastes a million times better than the beef from a barely-alive, antibiotic- dependent animal. The same goes for milk, eggs and chickens.
People seem to ignore the fact that most supermarket chickens sold for £2.99 are only 43 days old and cost less than a cup of coffee! Anyone who keeps chickens knows that a free range chicken has not bulked up to 2 kg by 43 days. So, what sort of life have those supermarket ‘identikit’ animals had? Maybe we don’t care enough. Nutrient analyses of fresh vegetables grown ‘well’ show a much broader range of macro and micro nutrients essential for healthy living. If we want to remain healthy we are dependent on these too, exactly because so many soils that cheap food is grown on are severely depleted of essential micro-nutrients like manganese, cobalt and especially selenium.
Lynne Boddy’s particular interest as a biologist is her research into the decomposition of wood in the wood-wide web by fungal mycelia and the contribution to the health of trees and shrubs by their association with mycorrhizae in soils. (‘Myco’ refers to fungus and ‘rhizo’ refers to root.) In general we only know about fungi as the mushrooms we eat or stamp on superstitiously, unless we happen to be unfortunate enough to have either dry rot, wet rot or honey fungus. The mushroom we eat is the equivalent in fungi to the flower in a plant. These aerial structures exist to distribute seeds and spores away from the parent organism. Unseen, below ground, the’ body’ of the fungus spreads out in all directions. Darwinian genetics reminds us that success of a species depends on its ability to adapt to the environment and that is what sexual reproduction allows- and what for many genera is becoming increasingly important as the ambient climate changes.
Plants and fungi, however, have another trick up their sleeve and can also multiply asexually by producing genetically identical individuals, as we know when we take cuttings of plants. Genetically this process is more risky as there is no possibility of adaptation if the climate changes. Soil fungi do this and thereby can colonise vast areas underground as long as the conditions are favourable in the immediate environment.
Saprophytic fungi in the soil play an essential role in releasing and recycling the nutrients trapped in dead and decaying material and making them available for new life forms. Increasingly we are beginning to understand that rather than being persistent spooky undertakers, these soil fungi also have beneficial associations with many plant species independently and collectively in their mycorrhizal forms.
These mycorrhizal associations are not pathogenic- like Armillaria spp (honey fungus) but commensal – meaning feeding at the same table or sharing nutrients. Commensal benign relationships between fungi and plants allow the fungus to grow and spread out and the tree or plants to maximise their biomass and immune health. Fungi do not photosynthesize as they don’t have any chlorophyll, but they have chitin which protects them from damage as the fine hyphal strands grow through the soil particles.
Similar to animals, fungi are heterotrophs; they acquire their food by absorbing dissolved molecules, typically by secreting digestive enzymes via the hyphal strands in the mycelium into their immediate environment. The association means that the host gets dissolved minerals, soil nutrients and water from the fungus and the fungus gets sugars from the plant. So this wood-wide web, which until recently has remained a big secret, is actually much older than our world-wide web and is yet another example of the essential environmental components that have been invisible to humans.
Despite our alleged superior intellect we don’t seem to have understood the Nature of the harmonious and intelligent relationships in the soil. To be a commensal is clever because, unlike a parasite, you don’t kill your host by pressing the self-destruct button and eating everything in sight. Fungi like Armillaria only benefit in the short term before they kill their host – although most fungi do have the ability to become saprophytes living off dead tissue.
By now I think we all agree that trees are essential- as indeed is grass- in providing carbon sequestration and increasing the oxygen in the atmosphere. If the survival of a tree depends on how ‘well rooted’ it is, it should also be obvious that the below-ground activity in the soil must not be interfered with by ploughing or applying huge volumes of chemical fertilisers or pesticides. Research has shown that altering the mineral ratios in soil by applying NPK fertilisers in excess, or glyphosate herbicide impacts enormously on the flora, fauna and fungi in the soil.
Lynne Boddy’s passion overflows when she describes filming the mycorrhizae in the soil. Using time-lapse photography and fluorescent markers she has shown the extent of a single fungal mycelium in a forest which can be several metres long. Work like this can surely only elicit respect for the fungi and their environment? Fungi are not the only soil micro-organisms maintaining the health of the soil by recycling and upcycling essential nutrients in that ecosystem.
What seems like a hundred years ago I worked at the Macaulay Institute for Soil Research, (now renamed The James Hutton Institute) in the department of soil microbiology. Many hours were whiled away observing soil protozoa (single-celled animals) using high magnification light microscopes (x 40-100), scanning electron microscopes (x 10k), transmission electron microscopes (x 40k) and cine photography, so that I had a unique insight into the secret life in soil. Slime moulds and soil ciliates didn’t seem very sexy in the 70s when everyone in Aberdeen was into oil big time.
Ironically the tables have turned and the microbial ecology of the soil and rhizosphere (area around the plant root) are now recognised as where the future lies, while the price of oil drops below zero for the first time ever! What I was researching was the relationship between soil organisms that might make them contenders for biological control agents for plant diseases, as well as improving the fertility of the soil. One ‘beast’ was a giant Vampyrelid amoeba (the stuff of sci fi films) which cut perfect holes in the spores of pathogenic fungi using digestive enzymes and ‘sucked’ out the contents.
The lock down has given us a unique opportunity to improve many aspects of our lives including what we can do to improve our own soils, whether they be in a field, a garden, in a pot on a patio or in a window box. If you have a garden you can cordon off an area to make compost from recycled kitchen waste and garden waste. Knowing how fungi decompose vegetation when it is moist, warm and well aerated is the key to good compost making, as well as encouraging reproduction of earthworms that simply munch their way through all the decomposing material. Keeping the correct ratio of green material to brown material in your compost heap is very important in providing optimal conditions. Green matter, such as grass or clover clippings and any legume debris, is nitrogen-rich. Brown matter, such as dry fallen leaves and chopped straw or hay, is carbon-rich. Mix these in a ratio of 2:1, green to brown, for a well-balanced compost pile. Ideally larger twigs and branches could be chipped or cut up with clippers so that their surface area to volume ratio is increased.
There are also liquid feeds available to speed up the rate of decomposition. Home composting means there are no transport costs, no plastic sacks used and you can also use the compost as a mulch before it is fully decomposed which then improves the water retention of the soil and improves its texture. Worm bins and Bokashi bins are also useful to have for munching up all kitchen waste. Worm bins, once set up are self-regulating with red worms chewing their way through the debris. Bokashi bins originated in Japan- maybe because many people live in close proximity without a garden, and can process all kitchen waste including fish and meat bones. They also yield a very potent liquid which when diluted 1:100 with water makes an excellent plant feed.
The degradation of the waste material is carried out by ‘good’ bacteria which are growing in bran with a molasses application and this is sprinkled on to the waste as you add it. Generally it is recommended that two bins are used so that one can mature as you fill the next one. They are ideal for very small gardens or patios where space is limited. They don’t smell terrible either! The contents of a Bokashi bin can either be added to a compost heap- the worms really love this mixture- or can be buried in a trench which later may be planted with vegetables or flowers.
Nettles and comfrey make excellent plant nutrient solutions when left to steep in a bucket or bin of water. Seaweed collected from the beach is also nutrient-rich as an application on the land but generally it is left in fresh water to desalinate for a year before use. It is also possible to buy mycorrhizae specially prepared for various plants’ specifications. They are particularly good to add to the surrounding soil when new trees are being transplanted. Any farmyard manure is of course an excellent addition. And last but not least, do harvest rain water.
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Further reading and links:
https://www.youtube.com/watch?v=nxgAR7fBUjY. A series of very short films made at the Macaulay Institute showing protozoa in the rhizosphere.
Graham Harvey: “We Want Real Food”, Robinson, London 2008
Graham Harvey: “The Carbon Fields”, Grass Roots, 2008
G. Henderson: “The Farming Ladder”, Faber, 1943
Jeff Lowenfels: “Teaming with Fungi”, Timber Press, Oregon, 2017
Peter Wohlleben: “The Hidden Life of Trees”, William Collins Publishers 2017,
Harvesting rainwater and compost bins etc. https://evengreener.com