The Lost Rainforests of Britain

By markontour, February 3, 2024

In the winter months I look for lichen. That habit, which I started because my binoculars are made temporarily redundant in January by reduced bird numbers on the uplands of the Bannau Brycheiniog, has developed new purpose since reading Guy Shrubsole’s magnificent ‘The Lost Rainforests of Britain’. Now I understand that the abundant varieties of these plant/fungi collaborations across the Welsh hills are not just distraction from the absence of something more exciting, but something incredible and historic in their own right – evidence of the last remaining fragments of the temperatre rainforests which once covered these isles.

Once you start looking for them, lichen are everywhere in the damp, woodlands where I spend my weekends. I noticed them first in aggregate – the fact that despite the trees shedding their leaves in a bid for protection against winter winds (which nevertheless brought down two ancient hazel trees onto the bridleway at the back of our house last week, turning the first section of my morning trail-run into a steeplechase), many of the woods of the Bannau Brycheiniog remain startlingly green all year round.

That’s the superpower of lichen, which is technically not a species in its own right but a collaboration between two organisms: an algae which captures energy from the weak winter sun, and fungi which anchors the plant to branches and rocks, while adding a contribution of the mineral nutrients which it absorbs from them.

Lichen appear in astonishing variety, from long trailing plants that make trees appear bearded, to ethereally grey, spindly reindeer moss (a lichen, despite its name), or the lollo bianco-resembling tree lungwort.

Largely ignored by twenty-first century humans, lichen and mosses were ancient Britons’ go-to ingredients for everything from medicinal cures to clothes dyes. Some of their names hint at this – “tree lungwort” is so named for its vague resemblance to our breathing organs, and for centuries it was used to treat diseases like asthma.

Shrubsole further explains that Celtic druids prided themselves on their knowledge of lichen and established their wizardly groves deep in woods of oak, hazel, birch, ash, rowan and holly, where lichen thrived. We know this from descriptions of the invading Roman armies and, at the other end of the so-called Dark Ages, the Welsh legends preserved in the Mabinogion – many of the stories of which take place in temperate rainforests. Indeed, the name of one of the central characters of the Mabinogion, the wizard Gwydion, means “wood knowledge” or “born of trees”.

No doubt influenced by these thousand year-old myths, temperate rainforests are also one of the most evocative locations in the ‘Lord of the Rings’ saga: Fangorn Forest. On entering this mysterious, ancient, and reputedly dangerous realm Pippin, one of the Hobbits, exclaims, “Look at all those weeping, trailing beards and whiskers of lichen.”

Tolkein was known to have spent a lot of time in the Bannau Brycheiniog while writing his masterpiece (a huge redwood tree along the Monmouth and Brecon canal is known locally as “Treebeard”), and I wonder know if he too went lichen spotting in the same damp places where I now spend my Sunday mornings?

Lichen thrive in woods where it is wet and mild enough for plants to grow on other plants – which describes pretty much everywhere near my Welsh home. Alongside the ferns and mosses that also contribute to the Bannau Brycheiniog’s winter greenery, and which themselves boast an even more impressive lineage dating back 350 million years, temperate rainforests once counted most of Ireland and the British isles as their domain.

Today things are rather different. A map which Guy Shrubsole collaborated in compiling shows twenty-first century temperate rainforests barely hanging on, confined now to woodlands along the west of Scotland, the English Lake District, Wales, Cornwall and Dartmoor in Devon.

‘The Lost Rainforests of Britain’ is not, however, a depressing “last chance to see” kind of tale. Shrubsole’s enthusiastic, flowing prose, allied to his campaigning mindset, makes ‘The Last Rainforests’ both a polemic on how to restore these extraordinary places and an uplifting page-turner, thrilling readers with tales of the extraordinary beauty which exists just outside our backdoors. “A visit to a rainforest feels to me”, glows Shrubsole at one point, “like going into a cathedral. Sunlight streams through the stained glass windows of translucent leaves, picking out the arches of tree trunks with their haloes of moss. They’re places that at once teem with life, and yet have a sepulchral stillness to them.”

Today, when someone mentions saving a rainforest most of us think of places south of the equator: the Amazon, the Congo, or maybe Indonesia. Vast woodlands that thrive in hot, humid conditions and which still sprawl over 12% of our planet’s landmass, even though they are under severe threat from industrial farming and urban sprawl. But temperate rainforests in middle latitudes were once just as prevalent, yet today they cover just 1% of the Earth’s surface.

Nothing can match the totemic and scientific importance of the Amazon to stopping climate breakdown and preserving the global eco-system which enables humans, and so many other living things, to survive and thrive. But for British environmentalists, preserving and restoring our temperate rainforests may turn out to be our Amazon.

Rewilding has rightly started to gather momentum as an environmental cause in my home country, and Shrubsole argues that enabling the natural regrowth of temperate rainforests would be a good focus for those seeking to implement their newly acquired rewilding handbooks. That’s because as well as offering opporutunities for homo sapiens to top up our endorphins, temperate rainforests are also extraordinary carbon sinks, hoovering up the greenhouse gases pumped into our atmosphere to fuel some of our bretheren’s lust for financial profit.

The key prescription Shrubsole advances to restore Britain’s temperate rainforests is to reduce, or at least territorially restrict, grazing livestock – sheep in Wales, and out of control deer populations in Scotland. ‘Lost Rainforests’ provides multiple reasons for optimism by detailing how a little bit of fencing is often all that is needed to keep out voracious grazers and for oak and other trees to self-regenerate ancient woodlands.

Even more straightforwardly, Shrubsole advocates for simply cataloguing the temperate rainforests that remain (astonishingly, many don’t appear at all on any official maps or records), in order to enable protected designations which would give these woods a chance to survive and thrive. Adopting a more people-centric version of the business adage often repeated by Mike Bloomberg: “You can only manage what you measure”, Shrubsole observes that “people who don’t know, don’t care”. The author himself has made a start by compiling an initial temperate rainforest map, presented in the book.

I write this having just returned from a run through Buckland Wood and up the barren sides of Tor y Foel. The contrast couldn’t have been starker – despite its small size, Buckland wood was teeming with bird-life and glowing green as the sun penetrated the clouds on a drizzly morning. It was exhilarating just to be part of the landscape. But as I slowly climbed (the peaks round here are not that high, but the gradients are fierce), temperate rainforest turned into monoculture pine plantation and sightings of other life grew slimmer. Until, for the last mile of the ascent the only company I had for acre upon acre of barren hillside, was the docile forms of sheep nibbling away at everything that sprouts from earthen origins, extinguishing any opportunity for the rainforest to seed new life before it can establish a root-hold.

Reading ‘The Lost Rainforests of Britain’ has added joy and knowledge to the privilege I already felt at having the opportunity to spend a little time in semi-wild places. What I now know to be temperate rainforests are where I feel most relaxed and alive. It has also educated me in the broader ecological value of lichen and the habitats where they thrive, and I highly recommend it to anyone who loves woodlands, or has always wanted to know more about that green stuff coating trees and rocks in winter.