Beneath the surface of our world, under every leaf and around every root grow hidden mycelial networks that connect ecosystems, cycle nutrients, and regulate the health of each landscape. Out of sight, these networks of fungi thread their way through the substrate of the Earth, regulating the flow of chemistry and information that turn individuals into interdependent communities. They’re incredibly resilient too - scientists have found evidence for a dramatic increase in fungi immediately after the mass die-off of plants and animals during the famous K-T extinction event that killed off most dinosaurs 65 million years ago.
Here in the Anthropocene, as the Sixth Great Extinction event unwinds before our eyes, fungi are now threatened with entirely novel problems never faced before - excess nitrogen pollution, herbicides, shifting temperatures and rainfall patterns, insect population collapses, and most importantly, extensive loss of habitat.
As I mentioned in my previous article on foraging, conservation mycology is lagging behind plant and animal conservation, yet new discoveries of the sheer importance of fungi in our ecosystems continue to build and astound the scientific community. A recent update of the The International Union for the Conservation of Nature (IUCN) Red List, the most comprehensive database of species and their extinction risk, now lists 343 species of fungi, 193 of which are threatened. Compare this with the 76,457 animals and 43,556 plants listed in the database, and you can start to see why there’s a lot of work to be done in mycology in the coming years.
Perhaps the biggest overarching goal of Myceliate is to inspire people to take action on protecting and restoring fungi in our local ecosystems, be that in our back gardens or in large-scale ecosystem restoration projects. There are things that we can all do as enthusiasts to add a touch of wildness to any patches of land we may have the chance to look after. But before we explore what fungal conservation might look like in your garden, let’s first get an understanding of how the fungal life cycle works so that we can be better prepared to create the optimal conditions for fungi to proliferate around us.
As fungi have taken an independent path on their journey of evolution, their reproductive cycles stand in contrast to the more familiar strategies of plants and animals. Unlike animals, fungi cannot acquire their food through physical movement and strength, and unlike plants, they do not form roots or photosynthesise. By learning the life cycle of a fungus, you can learn to intuit the conditions in your garden or local park needed to promote the growth of wild fungi, ensuring bountiful flushes of fruit bodies once the autumn months roll in.
Firstly, every mushroom begins with a spore, a microscopic pollen-like store of genetic material which wafts on the wind until it reaches a suitably moist, aerated and safe location such as a dead tree stump or a leafy forest floor. Its first baby step is to germinate and send out a single-celled thread that burrows its way through its substrate, the medium it is growing through. This thread is called a hypha, and it will keep reaching out until it finds another genetically compatible hypha to fuse with, for each spore only contains half the genetic material needed to form a viable fungus.
Once connected to a suitable partner, these hyphae (plural of hypha) experience a phase of energised growth, branching out in all directions to form an interwoven web known as mycelium. This mycelium will continue to feed and grow by exuding digestive enzymes that break down its substrate into small nutrients that it can absorb. Mycelium can grow indefinitely as long as there is food - in fact, the world’s oldest and largest organism is a Honey Fungus (Armillaria ostoyae) growing in the Oregon’s Malheur National Forest that is estimated at over 8,650 years old and spans 3,726,563 square metres.
Once this mycelium experiences changes in its environmental conditions - a drop in temperature, an increase in moisture, or the end of its food source - this will trigger the mycelium to begin shuttling its nutrients to a small knot of hyphae at the surface of its substrate, growing sometimes in the space of a few hours to form fruit bodies - the mushrooms, cups, earthballs, and earthstars that we’re more familiar with. On a typical cap-and-stipe mushroom the underside of its cap contains fertile tissue that produces spores and releases them into the open, sometimes in the hundreds of thousands, sometimes in the trillions. Each spore is a new combination of genetic material, holding the legacy of 1 billion years of fungal evolution to continue their circle of life once again.
As we have seen in the previous section, the food source and habitat of a fungus are one and the same thing: fungi live in their food, which (for important decomposer fungi) tends to be dead wood and leaves. Nutrients continuously get cycled from organism to organism, and as summer leaves become autumn duff, decomposer fungi begin their proliferation in earnest. These fungi are the decomposers, the saprotrophs. Some saprotrophs possess enzymes that are unique to fungi, making them the only creatures on Earth capable of breaking down complex molecules in wood such as lignin, and are responsible for over 90% of decomposition on the planet.
Here in the UK there’s a strange disposition amongst land managers towards avoiding decay, something that Benedict Macdonald, author of Rebirding, called “ecological tidiness disorder” where the untidy, messy sight of dead trees and rotting vegetation stirs them deeply with the urge to grub it all up and keep things neat and orderly. In recent decades, the need to make nature tidy has intensified, even in local parks and gardens where fallen branches and leaves routinely get raked up, put into plastic bins, and driven away. Removing dead wood removes biodiversity, and we must become acquainted with the wild, complex, and untamed look of functioning ecosystems if we are to live in a richer world.
In fact, this seems to be what people want. A recent YouGov poll showed that 70% of UK citizens want more wildlife in their green spaces as affection towards nature and its effects on our mental and physical health skyrocketed in the wake of the Coronavirus lockdowns. That being said, let’s now explore five principles for becoming a fungal conservationist in your own patch of land.
1. Let dead wood rot: Rewilding initiatives across the world regularly speak of the importance of letting the dead rest where they are, be it animal or plant in origin. Every species in a habitat has its own niche, its own behavioural space that it eked out over millennia, and those organisms that decompose and cycle nutrients back into the soil are losing out. Without the decomposers, there wouldn’t be soil, and ultimately, there wouldn’t be life. It doesn’t take more effort than to reserve areas around your habitat dedicated to fallen branches, logs and leaves. By allowing dead plant matter to build up we allow those wafting wild spores to find a home.
2. Mulch the soil: Bare soil is an open wound on the verdant skin of the Earth. In the wild, we only witness bare ground after catastrophes or after the small-scale activity of digging and burrowing animals. It isn’t long until pioneer plants eventually re-colonise those empty patches of soil. “Mulch” is the term used to describe the layer of organic matter that covers the ground, and it can come in the form of fallen leaves, twigs, and bark (as in a forest), or even cut plants. Many gardeners have fallen into the habit of excessively weeding and raking all bits of plant matter that fall on bare soil in attempt to remove any perceived imperfections. However, not only does exposed soil lose water very rapidly compared to mulch, but nutrients get degraded and washed away, and crucial fungi and bacteria die from exposure to UV rays from the sun, which gradually erodes the integrity of the soil. By mulching empty patches of ground, we can create food sources and habitat bridges for numerous species of saprotrophic fungi.
3. Abandon fertilisers and pesticides: The use of fertilisers in our fields, parks, and gardens has a major impact on fungal life even in surrounding areas such as forests, as nitrogen levels in many of these zones far exceeds what many soil-dwelling organisms can tolerate. Fungi depend on a certain balance of carbon to nitrogen, with carbon-rich soils being the prime location for fungal diversity. Pesticide use is another major cause of biodiversity loss in general, not just for fungi. These are molecules made to kill. As much as we notice so many differences between ourselves and all other non-human life, to a biochemist we are all staggeringly similar on a cellular level, so any novel chemical monkey wrench that lodges itself into the delicate biochemistry of one organism is likely to disrupt cellular signalling in another too. It is known that organic soils are not only more fertile in the long run, but also harbour more beneficial creatures than the brown dust that chemically saturated soils eventually turn into. So let us honour underground ecology, ditch the chemicals, and watch our soils myceliate back to life.
4. Plant mycorrhizal trees: Mycorrhizal fungi are a fascinating subset of fungi that form associations with living plant roots. They wrap themselves around or even penetrate root cells and set up exchanges in which the plants supply the fungi with photosynthesised carbohydrates, whilst the fungi supply the plants with nitrogen, phosphorus, and minerals. This is called mutualistic symbiosis, where both parties benefit from each other’s presence. Over 90% of all plants on Earth form these associations, and its possible that the very reason why plants evolved on land is because they set up nutrient exchanges with fungi long before soils existed. When trees grow in the wild, they make connections with other trees through these common mycelial networks that spread across the forest. These networks shuttle nutrients and information between trees, supporting growth, retaining moisture, and increasing resilience against environmental stress. When we plant trees, it is good practice to dip their roots in mycorrhizal spores or samples of healthy woodland soil to inoculate them with symbiotic fungi.
5. Collect IMO’s and radiate mycelium: The soils of healthy habitats are so rich in life that 1 teaspoon may contain up to 1,000,000,000 bacteria, and under every footstep may be up to 300 miles of mycelial threads. We can spread these populations of indigenous microorganisms (IMO’s) by excavating small amounts of healthy soil and bringing them to our gardens, or any grounds that are in need of revitalisation. Much like the way we eat probiotics - living cultures of beneficial bacteria - to inoculate our digestive systems and improve our microbiomes, so we inoculate our gardens with bacteria and fungi to improve soil health. Bacteria work closely with fungi, and it has been shown that fungi are capable of promoting the growth of specific species of bacteria on their hyphae. When we dig these into our soils, we allow them to radiate outwards, forming connections with plant roots and decomposing dead matter that effectively restores some wildness in our cultivated soils. Every patch of soil restored to health is a noble act of ecological restoration.
Any of my readers interested in ecological restoration, responsible land stewardship, conservation, and rewilding may have noticed what the title of this article has been alluding to. Tending the Wild, an fascinating book by Katherine Anderson explores how the rich wildlife of California was influenced by the knowledge and care of Indigenous communities, and swiftly dismantles the pervasive notion that humans are somehow scourges on the planet that always negatively impact their environment wherever they settle. Pioneer conservationist John Muir even thought that much of California before the arrival of Europeans was pristine, untouched wilderness, which still shapes our view of nature to this day.
It is now becoming clear that much of the Amazon rainforest and its incredible diversity has also been shaped by the human hand over the course of thousands of years. Humans have selectively grown and propagated numerous species of fruit and nut trees using polyculture and agroforestry techniques, and the result of their impact on their environment is now one of the richest terrestrial ecosystems on the planet.
Fungi, being the elusive organisms they are, have largely evaded scientific inquiry into past interaction with humans, but it would not surprise me if we soon discover that indigenous activity has beneficial effects on fungal populations. Currently, there is ongoing research into the ways in which we can improve the production of edible mushrooms in forests, which may even incentivise the protection and ecological stewardship of these habitats.
This is why I believe that by learning about fungi, we gain a better understanding of what it means to be human. For hundreds of thousands of years, humans have had a very predictable niche in every continent we inhabited, and we routinely opened up habitats for other creatures to thrive by virtue of our hunting, gathering, and horticultural ways. We enhanced ecosystems by living within them, we made them part of who we were and in turn, gave back through increased abundance. It is our nature to do this, and in the coming months we will further explore ways in which we can weave ourselves back into this mycelial web of life once again.