If you want to try to gain a full understanding of the growth and development of trees – fruit trees, any trees – then, as Merlin Sheldrake explains in his utterly fascinating book Entangled Life, you really do have to try to get to grips with the absolutely essential role that fungi and fungal networks play in the process.
Fungi are absolutely everywhere: in the air we breathe, the food and liquids (especially the alcoholic ones) we consume, living on and within our own bodies and, especially, in the ground beneath our feet. Silently, invisibly, individual fungal hyphae join together into vast, diverse mycorrhizal systems that permeate (and in many cases help to create) the soil, connect with the roots of the plants that grow in it, including trees of course, and then act as transporters of nutrients – exchanging phosphorus for complex carbohydrates – and senders of chemical signals from plant to plant; managing and fine-tuning the balance of growth throughout and within the plants that belong to their sphere of influence.
As Sheldrake explains, this isn’t some sort of parasitic leaching, or audacious theft by the fungi of the plants’ precious photosynthates. Instead, it’s a much more nuanced, mutually beneficial symbiosis, with both plants and fungi benefitting from the exchange of essential, life-giving chemicals and compounds. It’s a symbiosis that has been going on for millions of years and without which plants may not have evolved from their primordial ancestors, unable to access anywhere near as much of the phosphorus in the rocks and soils on which they depend for photosynthesis and growth.
A couple of years ago I read The Hidden Life of Trees by Peter Wohlleben. Like many people I was amazed by the concept of the ‘Wood Wide Web’ of mycelial networks that connect vast swathes of forest plants together. However, I was also deeply unimpressed by the book’s seeming lack of scientific analysis or explanation (an entire book on trees and as I recall, not a single mention of the vital roles played by phytohormones or plant growth regulators) as well as the author’s tendency to emotively anthropomorphise the relationships between trees in the network; ascribing very human agency and intent to the point of suggesting that trees might “care” for each other, for instance by deliberately choosing to nurture weaker members of their group and keeping ‘grandparent’ stumps alive long after the main body of the tree had gone.
Sheldrake politely but firmly puts Wohllebehn’s fanciful notions in their place, mainly by suggesting an inversion of the relationship: rather than looking at the (very visible) trees and assuming they must be in control of the nutrient exchange process via their subservient fungal minions, it makes much more sense if you take a myco-centric viewpoint: a fungal network will thrive better and for longer if it manages the distribution and balance of resources amongst its photosynthesising partners to prevent significant damage and losses. Thus, an ailing tree might be boosted with additional carbohydrates taken from other trees in the network, not to save the tree for the sake of the tree, but to prevent the loss of a useful node in the fungal partnership system.
Sheldrake also points out that the term “Wood Wide Web” itself is based on a very mechanical human construct – the Internet – which is the artificial antithesis of the completely natural, free-flowing, re-forming mycorrhizal networks that exist beneath the forest floor. It remains, however, a useful metaphor to encourage people to look beyond the above-ground and imagine the rich, vastly complex tapestry of life beneath their feet.
As orchardists, we’re essentially creators and custodians of artificial woodlands, so gaining a deeper understanding of the invisible links between the trees in our care must surely be an essential part of learning to work with and assist our charges. Thinking of our own Plot #79 orchard, it occurs to me that, by suppressing weeds with heavy-duty membrane and then covering that plastic with a few inches of woodchip, we may have inadvertently helped boost the mycorrhizal population of the plot. By introducing a significant potential food source for white rot fungi to gorge on, we’ve surely improved the chance of that same white rot fungi forming stronger networks of links between the trees, that might have helped our trees to grow and develop so well in the years since they were planted (and there was me thinking it was all down to the high quality pruning regime…)
Perhaps the potentially rich fungal environment also helps to explain the turnaround of our ‘Worcester Pearmain‘ tree, which appeared to be on the brink of death a couple of years ago but has made a remarkable recovery in the seasons since. Maybe the Plot #79 mycorrhizae simply swung into action, taking nutrients from the other trees on the plot – or even from the horsetail that persists despite our best efforts at removal – and rescuing the ailing Pearmain from extinction?
But back to the book: as well as the significant role of fungi in mycorrhizal relationships with photosynthesising plants, there’s plenty more fascinating insight into the history and future potential of fungal relationships with humanity; from the use of psilocybins (the substance that puts the ‘magic’ into “magic mushrooms”) to treat a wide range of psychological disorders including depression and anxiety, to the wide range of applications of fungal mycelia as fabrics, plastic-substitutes and even stronger-than-concrete building materials.
Along the way the author tells us of a potential solution for saving bees from varroa-borne viral infections (which links back neatly to orcharding and the bees’ essential role in crop pollination) and provides plenty of pointers to sources of additional information for anyone interested in growing their own mushrooms. He even confesses to making a very special and unique batch of cider (no spoilers from me though, you’ll have to read for yourself) and of course, there’s plenty of other content that I’ve not got time or space to mention, never mind to justice to, in this review.
I really cannot over-recommend this fascinating volume. It will open your eyes and your mind to the vast, mysterious, wonderful world of fungi and the multitude of ways in which we already interact with them (and they with us) on a daily basis, as well as the huge potential for expanding and developing those relationships for the future benefit and enrichment (maybe event the saving?) of our culture, society and indeed, our very humanity.
Entangled Life is published by Bodley Head (an imprint of Penguin Books) in the UK and is available from all good high street bookstores, as well as the following fine online retailing establishments: Amazon* | Book Depository* | Hive | Waterstones | WHSmith | Wordery
* = affiliate link – if you buy the book from here I’ll earn a small referral fee, which will go towards my next orcharding book.