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Replanting the Hebrides

  • Written by  Mark Rowe
  • Published in UK
The Calanais stone circle on the west coast of Lewis The Calanais stone circle on the west coast of Lewis (Image: Happylights/Shutterstock)
22 Jun
An ambitious, long-term project is hoping to bring trees back to the northern reaches of the UK

If you’re searching for the back of beyond in the UK, head for South Uist. Then, to head beyond the back of beyond, turn off the island’s A865 spinal route and follow the minor road that drills east through the rocky lochscape by the shores of Loch Aineort. Here, just beyond roads’ end above the loch, by a delectable burn (watercourse) called Allt Bholagair, you will find that rare thing in the Outer Hebrides: woodland.

This is not just any old woodland. ‘It’s absolutely perfect, absolute heaven,’ purrs Heather Beaton, the Uists warden for the RSPB. ‘It’s full of native ash, aspen and hazel, it has a really fabulous understorey. To go here is simply to step into the past.’

Allt Bholagair’s woodland is modest, covering approximately one hectare of a steep-sided gorge. ‘The bird species are great,’ says Beaton. ‘We get willow warblers, cuckoos, goldfinch, goldcrest, wrens, chiffchaff, blackbirds and woodcock. Sparrowhawks too.’ Rumour has it that dippers can also be seen on the burn. ‘Perhaps these birds are nothing startling compared to the mainland but they’re a really lovely treat out here,’ she adds.

Beaton’s dream, shared by others on the Outer Hebrides, is that over the coming decades and probably centuries, the islands will be gradually re-wooded, ideally in the fashion of Allt Bholagair. The process has already begun, with the launch of an ambitious planting scheme, the Hebridean Ark project. Supported by the Woodland Trust and the Forestry Commission, the Ark involves taking cuttings and seeds from surviving trees and propagating 100,000 saplings to plant across the northern island of Lewis and Harris. Beaton is keen to extend the scheme to North and South Uist and Benbecula.

The pre-Lapsarian connotations of the Ark project are not coincidental, for the ambition is to slowly roll the Hebridean landscape back several thousand years and return it to the state encountered by the first Neolithic – possibly Mediterranean – settlers.

At first glance, the re-forestation of the islands might seem incongruous, over-ambitious even. Today, most of the Western Isles are dominated by formidable moorland, a bleak, dramatically beautiful ‘peat-scape’ that draws away to the horizon. Pitted with lochans, ancient gneiss rocks and clumps of heather, this is a land of huge skies, where the sharp air is interrupted only by merlin and golden eagles on the hunt for prey, or perhaps a couple of ravens honking their way homewards. Trees, to put it bluntly, are as rare as hens’ teeth. Those trees you do see have been grown mainly over the past 150 years.

Yet the triumph of peat is a relatively recent phenomenon in the islands’ geological timeline. Five thousand years ago, the climate of the Outer Hebrides was significantly warmer and tree cover was almost complete. This was the landscape in which the enigmatic civilisations that built the haunting Calanais stone circle on the west coast of Lewis got to work. Slowly, the climate began to change, becoming cooler and wetter. Combined with grazing and clearing of forest, this prevented trees from re-establishing and peat began to take over. Several catalysts accelerated this process, including a volcanic eruption in Iceland around 1,000BC; the arrival of the Vikings around 800AD who saw the forests as an inexhaustible resource; and the battle in the Forest of Lewis in 1098, which saw a slash and burn policy and left Lewis on fire for days. Calanais itself yielded to the encroaching moors and when it was re-discovered in 1857, it lay under five feet of peat.

Cut peat drying on North Uist (Image: Joe Gough)Cut peat drying on North Uist (Image: Joe Gough)

A few miles north of Calanais, lies Horshader, mission control for the Ark project on Lewis. Here, David Murdo MacKay is at work in a polycrub tunnel – a strong, wind-resistant polytunnel made from recycled waste salmon pipes – building up a seed bank of species.

‘There’s a place for moorland,’ says MacKay. ‘Moorland is beautiful but there is also a balance. If you let nature heal then it can bounce back really strongly and reverse the damage we’ve done. Plant trees and we reverse the process of soil erosion, we bring wildlife back. Give birds some shelter and they will come and roost. It’s just about bringing the trees back from the brink. We [the Outer Hebrides] are a metaphorical ark out in the sea.’

The project requires some planning. Not least of these is the question of which trees to plant. Aspen, holly, juniper, birch and rowan are all native, but as Mackay points out, that is not always enough. ‘All the trees we’ve brought in the past have come from the mainland, there’s not really been any local trees planted, even though they are sourced from close by, from Skye, Oban and Sutherland,’ he says. ‘The environment is very extreme here. I’ve noticed the difference – the trees from the mainland don’t do as well. They don’t have the genetic make-up of the Hebrides trees. They get a grip but then get thrashed by the wind; the local ones grow straight up. The trees here have evolved to deal with the salt spray and gale force winds rather better than those in places where the climate is drier.’

MacKay points to a similar experience on Shetland, where rowans imported from Aberdeenshire simply failed to take off, prompting those pursuing a replanting scheme there to turn to seeds and saplings from the Faroe Islands. MacKay and colleagues have been forced to venture far and wide across Lewis and Harris to find the right trees from which to propagate.

‘We identified the Hebridean trees that were left on the islands,’ he explains. ‘What’s left is growing on cliff edges, crags, inaccessible places. These are very resilient trees in places that can’t be reached by deer.’ Sometimes, he says with a chuckle, they seem to grow from pure rock, from seeds dropped by birds. Aspen is particularly tenacious, with truly ancient specimens somehow ploughing its way upwards through the subsoil. ‘Some aspen can be linked back to the Bronze Age,’ says MacKay. ‘Where we find these scattered strands we have to protect them for ever. It’s a treasure house for genetic material, so it can easily disappear. The seeds are so important. ’

Aspen is a particularly hardy choice for replanting (Image: Andrew S/Shutterstock)Aspen is a particularly hardy choice for replanting (Image: Andrew S/Shutterstock)

Another challenge is the current climate, which remains perfect for peat. What’s more, those involved in replanting woodlands on the islands are aware of peat’s ability to lock up carbon. ‘Peat has become a big, big thing,’ says Beaton. For this reason the RSPB is not looking to plant trees on the peat as that could compromise its role as a carbon store. ‘We need to allow peat to do its things but we need to protect trees and create a robust habitat that can withstand climate change.’

In any case, Beaton feels that moorland and forests can sit perfectly well side by side. The dramatic landscapes around acidic Loch Druidibeag on South Uist, a few miles north of Loch Aineort are testament to this. Here, the peaty waters of the loch attract swans and golden plover; at the westernmost point, the loch is conjoined with the coastal meadows, known as the machair which in summer are carpeted in wild flowers and provide year-round sustenance to wading birds such as lapwings and oystercatchers. Very few trees are to be seen. Yet walk along the north shore of Druidibeag, where rocky headlands create lochs within lochs, and you come to sleepy Loch Hamascleit.

A small plantation of woodland runs on either side of the minor road here. Beaton calls it an ‘exclosure’. ‘We use that term because we are not enclosing the trees, we are excluding the herbivores – the sheep, deer and horses,’ she says. The intention is to weed out the non-native trees in what is otherwise a remnant ancient plantation. Native species abound, such as birch, grey willow, alders and rowan. ‘It’s exactly what you want from a native woodland,’ says Beaton. ‘But mixed in with it are Scots pine and rhododendron’ (Beaton refers to the latter as ‘rhodi’). ‘At the moment we are trying to remove the rhodi and hope to be rhodi-free by 2022.’ Compromise is involved: the non-native sitkas’ days may be numbered but for now they are tolerated as they provide shelter in which nascent native trees can grow.

The sparrowhawk is just one bird species to be found regularly visiting the Hebrides (Image: Petr Simon)The sparrowhawk is just one bird species to be found regularly visiting the Hebrides (Image: Petr Simon)

With the help of the Ark project, with which Beaton soon hopes the RSPB can be aligned, the hope is to bring back native species. ‘The moorlands are wonderful as they are but we should have more woodland here. My office looks out over the three hills of South Uist – they are just great but there is nothing on them. They are bare but there should be trees in their nooks, crannies and sheltered areas. We have to recognise that human impact has completely transformed the islands.’

As is the case further north, the RSPB will need to do its homework to ensure that the right sub-species are allowed to thrive. ‘This is something we talk about a fair bit,’ admits Beaton. ‘Although a lot of the trees around Loch Druidibeag are native, we don’t know their origin. It’s all about give and take. We know what we want to build towards but it’s not easy to do. To begin with we are very much experimenting. This is all in its infancy.’

Re-foresting the islands will also involve decisions about when not to intervene, when to resist the temptation to be hands-on. There will, says Beaton, be times when it’s best to just stand back and let nature take its course. ‘We would like the woodland to return by itself, it can do that,’ she says. Other potentially controversial choices may need to be taken to give the woods a helping hand: it may be necessary, Beaton cautions, to reduce the number of deer and sheep on the islands. ‘We want the woodland to return by itself but it won’t while all the herbivores enjoy munching the tasty aspen.’

Loch Druidibeag in front of Hecla mountain in South Uist (Image: Martin Fowler)Loch Druidibeag in front of Hecla mountain in South Uist (Image: Martin Fowler)

Like MacKay, Beaton rejects any suggestion that the project is driven by nostalgia; instead she points to the practical benefits. ‘We get migrants such as the willow warbler come here from Africa. They are looking for woodland and if there is a stable habitat they will come back year after year. If there isn’t, we will start losing them. The woods will also benefit humans. Woodlands are not just good for mental health, we know now that trees release chemicals that lower blood pressure.’

As the well-worn truism goes, society grows great when old men plant trees whose shade they know they shall never sit in. Those involved in reforesting the Hebrides recognise this as self-evident, not least in the long-term nature of their work. ‘I’m talking 200 years here,’ says Beaton. ‘I’m never going to see this but perhaps my children’s children will.’

MacKay also gazes down the long timeline that stretches out ahead. ‘We can’t do much about the climate, the peat is still there, but if we don’t grow the trees they will be gone forever,’ he says. ‘It depends on how you look at the world, where do we draw the line? We could just say we might have an ice age in 10,000 years’ time and be under a mile of ice, so do we decide to just let it die out? For some people a tree is just a tree but for some of us it’s a link to the past.’

Mark Rowe is the author of The Outer Hebrides, the Western Isles of Scotland from Lewis to Barra, published by Bradt

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