Why we all should get the ‘love bog’ bug
Back in November the National Trust for Scotland announced it was supporting the John Muir Trust’s efforts to frustrate the construction of a “city-sized” wind farm at Stronelairg in the Monadhiliath Mountains.
Among the many reasons which persuaded us that the site was unsuitable for turbines was its presence within one of Europe’s most extensive tracts of upland blanket bog.
The seemingly bleak moors and bogs of Scotland are one of the nation’s most familiar literary and cinematic clichés. Many would view these sodden, sucking mires as unproductive and may well welcome the fact that, by exploiting their open topography for wind generation, they can be put to use. This would be an unforgivably short-sighted point of view.
Blanket bog is only found in a few cool and wet parts of the world. Mosses and other plants break down over the decades and centuries to create a layer of peat which can be up to eight metres deep. This forms a habitat that dominates the landscape of upland Scotland.
The peat lands host a wide variety of vegetation and surface pool systems which in turn sustain an astonishing assortment of wildlife, including iconic moorland breeding birds such as the hen harrier, golden plover and red grouse.
But there is a more fundamental attribute to peat that makes it essential in the landscape. The sphagnum moss which drives peat formation holds significant amounts of water and releases it only slowly. This means it is held for long periods in the uplands before it finally filters towards the lowlands, so providing a degree of natural regulation which helps prevents downstream flooding. The slow and steady flow of water is also very helpful to another iconic species, the salmon.
The natural sogginess of the moss and the peat it forms has also come to play a crucial role in this era of man-made climate change.
Organic matter barely decomposes in cool, waterlogged conditions, which means that the carbon stored in the generations of plants and animals that make up the peat is locked away. That’s many millions of tonnes of carbon that would otherwise be released into the atmosphere, potentially stoking global warming still further.
That’s why the National Trust for Scotland (NTS) has embarked on work to restore peatland habitats. At Goatfell, Ben Lawers and Ben Lomond, surveys revealed damage to natural drainage systems and erosion caused partly by past agricultural practices. We have employed techniques that are genuinely experimental and are learning more each day as to what is achievable.
At Ben Lomond we first set about our tasks in 2009. We dammed up the artificial drains in 30 hectares of the Moin Eich, a large blanket bog lying between the mountain and Beinn Uird. Most of the bog here is on steeper slopes though, between seven and 14 degrees, and few repairs have been attempted on these gradients before.
Over 2014 we have blocked 2.5 km of drains on 22 hectares of steeper ground, using a mix of techniques including re-profiling and hand- and machine-built peat dams, with costs coming in at between £600 and £1000 a hectare. This is far more expensive that the costs incurred on flatter ground, of between £250 and £450. Damming the drainage cut into the peat by farmers re-establishes conditions favourable to new peat accumulation and allows flora and fauna to re-establish.
Most of Ben Lomond’s blanket peats are under one and half metres deep but on Moin Eich they easily be three times deeper. Vegetation is dominated by heather, cross-leaved heath and harestail cotton grass, as well as scarcer plants like the lesser twayblade and, of course, mosses. This rich, boggy carpet sustains bountiful insect life which in turn provides the foodstuff of larger species.
Ben Lomond is a magical place and our efforts to restore its peat lands have been funded through the Scottish Government’s Peatland Action scheme. Clearly, policy-makers have recognised the intrinsic value of these habitats for our environment.
Turning back to Stronelairg, it is therefore ironic that in trying to save the planet through renewable energy generation, the SSE energy company, with Scottish Government approval, wants to tear up an area of natural carbon regulation unsurpassed by anything in human technology.
This is no diatribe against wind energy – it will have to be part of the mix if we are serious about tackling climate change. However, we need to be careful where we place such developments and we would all be advised to learn to love a bog.
• Alasdair Eckersall is a property manager and senior ranger with the National Trust for Scotland based at Ben Lomond. www.nts.org.uk