The wood wide web
Most laypeople with even a passing interest in ecology and wildlife preservation will have heard the term ‘wood wide web’ at some point in the past few years. It is the colloquial name for what is more accurately termed the ‘common mycorrhizal network’, a subterranean symbiotic system of fungal organisms and plant roots, found in virtually every woodland. Nutrients such as carbon, phosphates, potassium, and other critical resources, are shared amongst the connected parties in a manner not easily explained by theories of evolution which centre around competition for survival, in contrast to cooperation. (Symbiosis between different organisms is a concept well understood, of course, but not at such a complex level as this.)
Some studies even report that connected organisms can exchange ‘messages’ in the form of enzymes, facilitating the coordination of defence against insect and pathogen threats.
It is hardly surprising to see how such findings, seemingly underpinned by scientific rigour, could capture the imagination: revealing a world quasi-sentient forests in which trees ‘talk’ to one another, share food and even fight their enemies together. (Fans of Tolkien may even be put in mind of his ‘Ents’: benevolent mythical beings who live amongst and shepherd the trees, and who are themselves very tree-like.)
The concept originated with arboreal ecologist Suzanne Simard, and broke into the mainstream via her 2021 book Finding the Mother Tree. As is so often the case when new theories break out into the lay community, the ‘wood wide web’ hypothesis was co-opted and distorted, arguably far beyond what the underlying facts supported. (Think about quantum entanglement, referring to the mysterious linkage of subatomic particles, and how it has been appropriated to explain pseudo- or non-scientific concepts of telepathy, psychokinesis and even guardian angels.)

As Sophie Yeo, Inkwell Journal editor, puts it in a recent Guardian article, ‘The explosion of interest [in the wood wide web] comes from…what the theory implies: that the natural world is not static and cruel, but rather a living community governed by the same moral principles as our own. But trouble arises when a scientific theory gains a life of its own, becoming culturally relevant in a way that ignores, simplifies, or contradicts the facts that birthed it.’
In 2023, measured pushback came in the form of a paper published by three scientists, led by Justine Karst at the University of Alberta, who concluded that, whereas the mycorrhizal networks existed beyond any doubt, the evidentiary basis for what it was claimed they did, or could do, was rather slim, and further work was required.
What happened next was a rather unseemly ad hominem attack on Karst by Simard, including the inference that Karst’s objectivity was imperilled by part of her funding coming from the Canadian Oil Sands Innovation Alliance.
Pining for what is lost
Yeo links this case with another, which will resonate with the UK rewilding community; that of the ‘Great Wood of Caledon’, as it is sometimes called, being the fanciful notion that the Scottish Highlands were once almost entirely covered, by a vast and interconnected pinewood, and that it was felled by humans. In fact, to the extent that such a mega forest even existed, which is unclear, the paleo-ecological evidence suggests that its decline was caused mainly by climate change in a prehistoric era, hundreds if not thousands of years before local human tribes were of a sufficient size that their tree-felling could have a noticeable impact.
So how has the myth come to take hold? Partly it may be confirmation bias.
As sylvan gems such as the Amazon rainforest are quite explicitly under threat from human activity, it is tempting to believe that, much closer to home, and surrounded by so many examples of wildlife depletion, we had our own great forest too, and owe it to ourselves to restore that forest.
There may be social factors at play, also. Land ownership in the Highlands remains relatively concentrated (according to one study, just 433 people and companies own half of all privately-owned rural land in Scotland). This is in part due to historic ‘Enclosure’ laws, passed between 1604 and 1914, which had the effect of clearing and consolidating ownership of some 28,000 square kilometres of land, and in the process dispossessing tens of thousands of tenants, primarily to improve agricultural output for a small number of wealthy landowners. To this day, many estates have been content to manage their land to optimise grouse moors and deer stalking, both of which can indirectly suppress tree growth, as well as commercial forestry, which prioritises a relatively unhealthy monoculture.
Barren hillsides are thus symbolic of that enduring sense of social injustice, just as new, non-commercial plantations could be seen to symbolise some form of redress: land enclosed from deer cannot sustain them, nor maximise timber yields for the landowner.
Throwing shade
But does the mythology of the ‘Great Wood of Caledon’ undermine what many Scottish landowners and activists – such as Trees for Life’s James Rainey – are doing to encourage tree planting and nature-aided forest regrowth?
No, and not least because this myth too is rooted – pun intended – in fact. It is undoubtedly true that the Highlands were home to ancient woodlands, and that their decline over thousands of years was accelerated by human behaviour, particularly in the last century. After the Second World War, and perhaps understandably, the nation was focused on creating strategic, local resources, which led to the last holdouts of these ancient woods being cleared for commercial forestry. Commercial trees, such as the Sitka spruce, are less appealing to herbivores – mainly Red and Sika deer – exacerbating the problem for the native Scots pine. It is also the case that headline-grabbing fauna, such as wolves, lynx and wildcat – all extinct, or virtually extinct in the case of the wildcat, due to hunting and habitat destruction – would depend for their successful reintroduction on large woodland ranges.
Restoration of the woodland is nevertheless possible due the remarkable resilience of pine seeds, which can lie dormant in the soil for years and years. Clear away the shade of fast-growing commercial forestry and these seeds – 85,000 or so, according to Trees for Life – will germinate. Enclose them, and they will be protected from herbivores. And who knows, within a few decades these seeds will be a new and wild forest, aided in their growth by a hectares-wide mycorrhizal network, unfenced but with deer kept away by roving wolf packs. A wood wide web indeed.
Takeaways
The planting and maintenance of woodland can give rise to tradable natural capital assets, reflecting the carbon dioxide sequestered by woodland creation. The most widely recognised framework under which carbon offset units are verified is the Woodland Carbon Code, or WCC. Backed by the UK government, within this framework landowners can register, validate and verify eligible afforestation projects on the UK Land Carbon Registry, to quantify the number of carbon units new woodlands will sequester over a specified length of time.
No matter how far along in the process you are – whether you have units to sell or are simply open to the idea of planting trees to sequester carbon – your first step should be register your land. Landowners with units to sell can be connected with buyers; those with only the idea of selling can be connected with vetted ecologists and landscape architects, with whom to partner of the journey.
You can find out more about the work of Trees for Life here.