Of how about 444 million years ago in the Silurain period when the granite that now forms the high mountain areas of the Cairngorms rose as a molten mass from deep within the earth to within a few kilometres of the surface? Or perhaps 416 million years ago in the Devonian period when the huge Caledonian mountain range of Alpine scale was beginning to erode down to the lesser heights of today, and the landmass that is now Scotland was still 10 degrees south of the equator and still to move north through continental drift to where it is today?
Well to understand what we see in the Cairngorms today, perhaps the most useful starting point is just a mere 66 million years ago at the end of the Cretaceous period. By then the once towering Caledonian mountains hade been eroded down to a more gently undulating, quite low-lying plane, called a peneplane, of gentle slopes and wide valleys. Then, over the next 60 million years, this peneplane was raised up by geological forces to form an elevated plateau.
Then came the ice! About 2.6 million years ago, successive ice ages began advancing and retreating with cycles of climate change. For at least the last 80,000 years, the glaciers and meltwaters of successive ice ages have cut into and moulded the Scottish landscape and for about 80% of that time, this has happened in the Cairngorms. The massive iceflows of the glaciers gouged out the huge corries and steep sided glens we see today. But not all of the Cairngorms was impacted in this way. Because of high altitude and the then relatively dry climate, on the higher areas, the icecaps formed held firm and immobile, gripping the underlying rocks. They caused little erosion of the underlying land. The hardness of the granitic rocks assisted in resisting erosion. During the ice ages, the Cairngorms massif was one of the few areas not overrun by the larger Scottish ice sheet which flowed around them. As a result, the high plateau areas were not markedly changed.
A mere 11,500 years ago, the climate warmed and the ice retreated. The immense corries and deep valleys revealed their ice-sculptured forms, and the lower lying straths revealed and were shaped more by the eroding power of the rivers and meltwaters. But the plateau areas revealed a much, much, older pre-iceage landscape dating back hundreds of millions of years! It is striking to think that the smoothly rounded tors of Ben Avon and other Cairngorm Mountains formed when the Caledonian mountains were eroded down to a low-lying, rolling plane and are probably immensely older than the mountains your see around you as you stand beside them.
So, as you journey from the lowland straths, up past the corries to the plateau, you journey from landscapes fashioned by rivers and meltwaters of glaciers, through a dramatic landscape of corries and glens ripped out of the high plateau areas by glaciers, to a rolling much more ancient landscape. Parallel to this, you experience an ecological journey moulded by forces like increasing harshness of climate and exposure with rising altitude, paralleled by increasingly poorer, less fertile and thinner soils. Starting in the forests and agricultural grasslands of the straths, up through the timber line to where only scrub survives and finally up through that to the artic tundra of the plateaux. The birds, animals, insects and flowers you see change in concourse with this.
The exhilarating progress from Caledonian woodland through scrub to open hill takes one to a land where thin soils and a harsh climate will forever dictate a treeless landscape.
Roots to Summits
Report of a conference reviewing the future of the Cairngorms Mountain Woodlands
Pub The Cairngorms Campaign 2002
Considering these in turn, around one third of the area is above the natural treeline of 600-650m, making it the largest area of montane habitat in the UK. Here is one of the most important areas for mountain wildlife in the European Union containing, in addition, an outstanding concentration of preglacial, glacial and postglacial landforms. The forests and woodlands contain the largest areas of semi-natural woodland habitats in the UK and, within these, the largest surviving fragments and greatest total area of Caledonian pinewoods.
Although wetland habitats occupy only a very small percentage of the area there is still a great diversity of them. Water habitats such as high level lochs and major river systems are noted for their high degree of naturalness, biodiversity and quality of freshwater habitats. They have a range of national and international designations including Ramsar and the two major river systems of the Spey and Dee are SACs.
The farmland and grassland habitats have not received such protection but harbour many plant, animal, bird and fungal species and, in their role of providing linkage to other habitats, support a range of bird and animal species.