We walked from Achnaha to Ardnamurchan's north coast this morning in the company of Rob Gill, a local businessman who runs Geosec Slides, a company which cuts rock thin sections for mounting on slides - website
here. While our purpose was to look at some interesting geology in the area around Glendrian Caves, it was simply wonderful to be walking in such exceptional weather. While the rest of the UK seems to be in the grip of winter, our days are sunny and clear, though the cold nights continue - yesterday midday the air temperature reached 9C, and plunged to -2C overnight, giving us a thick frost.
We walked across the flat land to the north of Achanaha, and then, faced by the line of hills formed by the great eucrite of the Ardnamurchan volcanic ring complex....
....found a gap which gave us out first view of the Lesser Isles - that's Muck and Rum in the distance. The boulder in the gap may have some significance, as the nearest outcrop of the rock type of which it is formed, tonalite, is a mile or so away. It may be that it was moved there by a glacier, but it may also have been placed by man as a land marker or to guard the gap.
Once through the hills we looked westwards to the white houses of Lower Sanna, and beyond to the island of Coll....
....and northwest to one of West Ardnamurchan's beautiful secluded beaches.
After completing our geological investigations - about which more in a later post - we retraced our steps, to find our route back to the car cut off by a muirburn. This one was fully under control - so we were assured by those conducting it - and all the legal requirements had been met. These controls are far from straightforward:
this link gives some idea of the minefield of regulations which have to be obeyed.
In the end we simply walked through the area being burned. The burn on this land isn't deep - despite the fact that we've had no significant rain for some six weeks, the peat here is sopping wet underfoot.
Meanwhile, the fire near Strontian continues to burn. Kilchoan fire team were fighting it again yesterday afternoon, arriving home about 9.30pm, but they're been given today off. Two helicopters have been brought in the bomb the worst areas with water. Meanwhile fires have been raging at Arisaig and on the Sleat peninsula on the south side of Skye, that fire easily visible from the north coast.
Why do they do it?
ReplyDeleteJust because muirburn is a (fairly) old tradition, it doesn't mean that it's a good thing to do. We've stopped sending children down the pit or up chimneys, for example. It's very, very bad for the environment (just think of your pics of snakes burned alive last year - and no doubt other creatures suffered horribly, too - and look at the pollution in our skies right now.) In fact - very, very often - burning doesn't improve grazing. In fact, it often ENCOURAGES bracken.
As long ago as 1977, in his classic work (The New Naturalist:The Highlands and Islands, Collins UK, p 95 ff) pioneer environmentalist F Fraser Darling warned:
"It [muirburn] is a traditional practice,and tradition dies hard in the conservative mind. ...[however] if regeneration of heather does not take place without delay it may be replaced by moor grass or bracken. ...
But in the West Highland Hills where sedge and flying bent are much denser [than heather] on the ground, a hill ought not to be burnt ofterner than once in twenty years. It is unfortunate, therefore, that burning in the West and North West Highlands is such a haphazard affair.
The theory is that where burning has taken place there comes an early bite of moor grass. Those early stems may appear in extremely low density, and after the ground has been punished by the sheep it lies derelict for a long time, giving neither food nor shelter for bird nor beast. By far the biggest trouble arising from this indiscriminate over-burning in the west is the subsequent spread of bracken, which growns strongest where it is free from competition ...."
The ecological points are hard to dispute. However, not many people would be too happy to be asked to live and store all their possessions next to a tinder dry primed bonfire. The equivalent of a powder keg is now all around highland homes home after our dry winter.
ReplyDeleteThe bleached and dead grasses, the brittle dry clumps of heather, and the frost damaged fronds of mosses need only the slightest ember to set them ablaze. There is a real risk to livestock, fences, cables and other property damage if the dead undecayed growth is not removed under control. . The dead material shades and smothers new growth.
Of course old bottle glass, carried to the hills on a warm summers day, then carelessly left behind does not decay. Frost-heave can lift hard objects, forcing old glass up to the surface of the frozen peat again as glass catches the sun and warms in the frosted ground.. Prisms of sunshine through this broken glass can and do ignite the tinder...self ignited fires are potentially lethal. The debate will go on.
Many thanks for these thoughtful points. Jon
ReplyDeletePossibly the best course of action if next to a tinder dry bonfire or powder keg is NOT to set fire to it. The trigger for new growth in spring is generally soil temperature not available sunlight. This is why the grass is late growing this year. Removing last years cover also removes the microclimate at soil level and opens the soil to radiating all its heat to the clear night sky. Burning also reduces the number of seeds on the soil surface, and thus the regeneration of annual grasses. Tougher perennials will become more common, but these are not as palatable to stock.
ReplyDeleteI must say I agree with the comment immediately above. There must be a better way of managing a fire-risk than by starting fires. A run-away muirburn fire came uncomfortably close to our house the other day, but was safely extinguished by our wonderful local Fire Brigade. No damage done - and absolutely no blame attached to anyone. No muirbuner plans for their fire to get out of control, but, as we have seen in many places recently, it so often happens.
ReplyDeleteTo take up the other points mentioned in the second comment above, a house is surely more important than a fence, and, by law, electricity cables should either be high overhead or buried well below the surface. In both cases, they are not in much danger from grass fires. Of course, no-one wants to see livestock harmed, but I expect that intentional muirburn has killed many more wild creatures than sheep or cattle.
And, while there is indeed some dangerous old glass around, is the sun at this time of year really strong enough to start frequent fires on frozen ground through glass fragments? Do we have any facts and figures? Is it not more likely - as has happened here in Ardnamurchan not so long ago - that accidental grassland fires are caused by avoidable human actions, such as discarded cigarettes or carelessly-lit campfires or bonfires?
The rhetorical question in this 5th comment - "there must be a better way to manage unacceptable fire- risk than by starting fires" - remains to taunt us 3 days on.
ReplyDeleteWhen there has been no appreciable rainfall for over a month, the alternative management of soaking ground all around houses seems a bit selfish in view of limited shared drinking-water and fire fighting resources.
Wishing to conserve the natural groundcover around ones house is full of risks. What view do insurance companies have of failure to take what many regard as reasonable precautions to safeguard homes by forming proper firebreaks. ?
Locally, on Ardnamurchan it can be seen that not all telephone cables are always safe underground. The cables that connected Portuairk were destroyed in a recent muirburn season. Electricity cables to houses on the peninsular descend poles from transformers to enter the ground nearby. These plastic coated cables are also vunerable in grass fires. Where any type of cable or pipes are run across rock the depth of soil is often insufficient to protect them.
It might not be so bad if those who are assumed to have lit these fires would stay beside them, be seen to be attempting to control them and own up when things escape their management. In truth some of our local wild fires do appear to have started quite spontaneously. A few commenced some considerable distance out from the road side. No one would have gone out there to do this. In the absence of lightening strike there is no other reasonable explanation than discarded bottle glass.
As for frost heave lifting objects that retain warmth from the sun, out from a frozen substrate. This is a phenomenon that geologists can confirm from study of tundra and permafrost regions where part buried rocks rise to the surface.
As stated earlier ..the debate will continue. We should stand in awe of the sheer dedication and determination of our local volunteer fire crews across the west Highlands over recent days. We owe them our deep admiration and gratitude.