Bookending Killin with unofficial trips by Robert Goodison

Wednesday June 21st Creag an Lochain South (The dam end cliffs) Meall nan Tarmachan.

Monday June 26th Coire Riadhailt, Meall nan Tarmachan

Thanks to breaking my belt on the Tuesday night just before departure and some last minute purchasing en route north, I missed the Balquhidder walk start by over an hour (i.e. the first day of the BBG holiday to Tayside in central Scotland) and so I bolted for the southern cliffs at Tarmachan by the ‘Lawers Dam’ instead, as a ‘what to do if you’ve less than 2 hours free’ before getting ready for the evening meal get-together. As such, I only noted the main species and took a limited number of photographs. There is a high degree of overlap with the final day’s trip save that, with a more south-facing aspect, tall herbs are more prevalent than the alpines and, if Woodsia is still present, it will take hunting for, as it is scarcer here. Also, the massive colony of Wood Vetch (Ervilia sylvatica) does not occur to the north. It’s also the location I first saw Don’s Twitch (Elymus caninus - ex Agropyron donianum), when it was considered a discrete micro species or variety and I was chasing things from the old 1956 New Naturalist Volume 33 J. Walters and M. Raven Mountain Flowers Book. Now it is merely a shaved or awn-less form of Bearded Couch. Taxonomist’s eh! But re-finding it would take more time than I had available that afternoon as I recall it lies across at least two or three hundred metres of very rough terrain.

The site’s name hails from the Gaelic for Cliff of the Mountain Tarn or Small Lake, itself part of Hill of the Ptarmigan, the montane grouse. Gaelic would once have been the prevalent language of the area, plus a greater rural population, but both are now long gone. But that is another story and an essay, if not a history book, in itself. There was long a natural tarn or small lake here but it was greatly enlarged in the early 1950s by the building of the dam as part of the Braedalbane Hydro Electric Scheme gathering water piped from the surrounding hills and draining through pipes supplying the Finlarig Power Station just outside Killin into Loch Tay1.

Both of the sites visited here and the northern cliffs of Creag an Lochain benefit from lying on the same Ben Lawers Schists band, between two and four kilometres broad, as the famous hill itself, broadly formed of base rich rocks2.

Parking at the dam, a good half mile beyond the Lawers car park (it is no longer formally marked with a P parking symbol, so don’t block any works access), I crossed the dam wall via a gated step in the ironwork fence to the west bank of the reservoir for the short approach. When I arrived the Wood Vetch was in full bloom, the best display I have yet seen. Scorched grass, such as on the crags, showed how dry the summer had been until recently. The herbs around the vetch like Melancholy Thistle (Cirsium heterophyllum), Wood Crane's-bill (Geranium sylvaticum), Globeflower (Trollius europaeus) and Meadowsweet (Filipendula ulmaria), would not disgrace a good ‘Upland/Northern/Dales Hay Meadow’ (National Vegetation Classification MG3b) but this is it’s montane equivalent (U17 Upland or Hydrophilous Tall Herb Vegetation)3. In 2000, an electric fence was erected around 180 ha of this site to exclude sheep and deer in an attempt to restore the threatened Upland Tall Herb Vegetation which was confined to cliff ledges and had been suppressed elsewhere by overgrazing. Survey work between 1999 and 2017 has shown that, whilst overall species diversity is essentially unchanged, there has been a near 30% expansion of the tall herb component. Understorey species such as Wood Anemone (Anemone nemorosa) have also benefitted from the increased shade brought about by restricted grazing.

The approach now has a mix of natural scrubbing up, significantly enhanced by planting of trees and montane willow species such as Downy Willow (Salix lapponum). The site is best visited in small groups as the terrain is relatively steep and uneven. The increased vegetation height and cover hides rocks and hollows making it difficult not to make at least temporary trampling damage. It is well worth a visit in June or July and I suspect a thorough exploration or a half day at either end of the Lochan could easily fill a day. Small-white Orchid (Pseudorchis albida) was seen some twenty years back on crags upslope, but closer to the dam. Like many of the more south facing Tarmachan sites, Alpine Cinquefoil (Potentilla crantzii) is much commoner than on Lawers and normally easily found earlier in summer here without the need for a ‘big climb’. With limited time I’ve had to import an old photograph, although the group was fortunate to catch the plant on the far cliffs of ‘The Hanging Gardens’ this year on the first full day’s walk. Both ends of the cliffs would be a fine full-day expedition, although I suspect for most sane people they are better done as two short walks rather than trying to traverse the rough intervening terrain (plus a headland of cliffs forces you down to almost loch level and then you have to return the same way or take the tarmac road along the eastern bank back to the start).

Coire Riadhailt

Bruce had suggested Coire Riadhailt as a walk even before our departure to Killin to see an unusually large colony of the rare Mountain Bladder-fern (Cystopteris montana). It appeared on the potential itinerary for the group for the week. I had long eyed up this face of the mountain on trips over from Loch Tay, past the Lawers walk start, and Creag an Lochain into Glen Lyon and back. I’d done the northern cliffs that we’ve usually terminated the BBG holiday hereabouts with so many times before, both with the Group and about every second visit I’d made to the Highlands since the 1990s, either as a starter on the way north or a convenient calling off point heading south. So it seemed such a shame not to attempt Riadhailt given the trip had shown my hill walking was now nowhere near what it used to be and some older group members had opted out of the mountain options earlier, so would there be another chance? Not to mention it’s another best part of 600 miles round travel to come back. So as Bruce Guthro had once said a few years back “Scotland! Let’s do this!”

Having seen the main group safely assembling at Creag an Lochain, I headed over to the col and parked in an extended layby (large enough for 2 cars at the back of a ‘no parking’ passing place) before heading off south westwards along a green old hydro track through Coire Ghlas, the appropriately named green corrie, towards my objective. The ruined bases of shielings recall the days of much earlier transhumance agriculture, when in summer, men and, more often, the women and children, would tend to the cattle and sheep on the high summer pastures so what little productive land there was in the glens could grow subsistence crops for the winter months, in a time without machines for any assistance. The song lyrics ‘where the breathing of the vanished lies in acres round my feet’ very much echo through my mind4. Whilst hard beyond any modern standards, the land was not always this empty of people.

Once past the hydro workings I checked my GPS and I noted I was only a kilometre north of the fern location, so as the slopes ahead appeared to be a relatively simple grassy bog, I decided to make a bee line south ‘off piste’ past flushed ground rich with Scottish Asphodel (Tofieldia pusilla). There is no path much beyond anyway, so at some point or other you have to make your own way. Peppered by occasional showers rattling in from the northwest, I paused briefly on a breather to glance down and spotted a fine Lesser Twayblade (Neottia cordata), growing directly out of a clump of Sphagnum.

With few decent intermediate aim points, I drifted somewhat off my bearing, slogging upslope and leap frogging small streams. That left the last couple of hundred metres outbound more of a careful undulating traverse, more westward avoiding any drops. By now I was in Coire Riadhailt proper, the exact translation of which I’m uncertain, but Corrie of the Queen’s Burn is not unrealistic, as Righ means King and Allt a mountain stream, gill or burn. Passing high altitude flushes, including a little Russet sedge (Carex saxatilis), that we had seen earlier in the stay on Lawers, I steering around rock outcrops and ignored a mountain ringlet I spooked, given on this difficult terrain there was no way I was chasing it with a camera. With hindsight I would have been better following the corrie burns until much closer to my target gully, but you can’t turn back time.

I ended up breaking my own rules by pushing past my ‘turn back to the car’ time and descended into a gully from which I was neither 100% sure of reversing or finding a safe exit ahead, but I was so close I could see the plant. Anyway, there before me was a bank bedecked with Mountain Bladder-fern (Cystopteris montana) covering some two or three square metres, large by Scottish, if not world, standards. In the wild it is now restricted to a few wet gullies and north facing cliffs in the Highlands, having only one century ago reputedly having had one colony on Helvellyn wiped out by a rock-fall rather than the usual fate of collecting rare ferns to death. None are easy. But such impressive surroundings and every time the sun broke through and raced across the corrie, light sparkled off waterslides and added depth to the terrain. With photographs now taken, it was time at last to find a safe way down the loose scree in the gully below, take a very belated lunch and head back to the distant car for an even longer drive home. Truly a fitting and epic end to a superb holiday.

Footnotes

1 Lochan na Lairige itself means the Tarn/Mountain or small lake of the Pass. Bealach is probably the more widely used Gaelic name of a pass although there are other ‘Lairigs’ around, most notably the Lairig Ghru, either Dhru/Ghru’s Pass, or more likely a corruption of The Oozes/Ouzing Pass that splits the great Cairngorm massif in two, east and west, given the infant River Dee spills southward and then eastwards towards Braemar, Royal Deeside and the coast.

2 Although in practice, this is still a series of rocks ranging from friable so called ‘limestones’ or calc-schists through more massive schists and coarser more sandstone-like ‘psammite’ rocks to outright base-poor quartzites. Due to high rainfall and the effects of leaching, even here, it is not difficult to find acid-loving vegetation. Due to the effects of loess soils, boulder clay and peat formation covering the bedrock, as is widely seen in the Dales and wider Pennines, herein lies one of the dangers for our alpines with climate change, in that there are few places higher with base-rich rocks that they can retreat to, even if isolation and inbreeding of the rarest species doesn’t get them first. The rocks lie in a synform, an apparent ‘U’ fold, although it has to be remembered that here we are in the eroded out roots of a once much greater mountain belt that included Norway and the Appalachians that were once contiguous when joined as a super-continent. What we see now is large parts of the basal limb of a massive Scotland-wide ‘collapsed onto its side’ over-fold whose tip lies miles to the south-east, immediately north of places like Aberfoyle, Callander, Crieff and Dunkeld, close to the Highland Boundary Fault. This is the Tay Nappe and within it features like the component synform are actually inverted, in this case anticline or ‘arch’. Most of the structure has gone and has to be interpreted from what is left. The Nappe is one of several similar structures across the Highlands brought about by a local shortening of the earth’s crust, as earlier ‘versions’ of Europe and North America collided through a pre-Atlantic or Iapetus ocean closure, although in most the deformation is orientated more to the north-west. Unlike our relatively simple geological structures nearer home, the oldest rocks lie at the axis of this synform and here get younger both away from it and with depth. The rocks are of ‘Dalradian’ age, although that of itself hides a multitude of sins, as across the whole ‘Supergroup’ they range from roughly 800 million years ago (definitely Precambrian age) to certainly Cambrian and almost certainly the Ordovician Period circa 470 million years ago, although future research on mineralisation may refine matters further. A date of just under 630 million yeas ago is likely for those around Ben Lawers, almost double that of our local Great Scar Limestone based on studies of the development of the goldfield around relatively nearby Tyndrum.

3 Vegetation types from the National Vegetation Classification as described in British Plant Communities, J. S. Rodwell.

4 ‘And I step the naked heath, where the breathing of the vanished, lies in acres round my feet’ are lyrics from the song ‘Flower of the West’ by Scottish Celtic rock group Runrig.

Text and photographs by Robert Goodison

Read a summary of the group holiday to Tayside here:

21-26th June 2023 Tayside, central Scotland