For tens of thousands of years the Scottish Highlands were covered with ice, thousands of feet thick. About 10,000 years ago the ice retreated leaving the hills and valleys much as they are today.
Vegetation colonised the bare land – at first mosses and lichens, then the flowering plants with bushes and trees. Birch, willow and alder were the first trees to arrive, followed by Scots pine and oak.
About 6,000 years ago, the warming climate reached an optimum for tree growth, and forest covered most of Scotland to an altitude of about 600 metres (2,000 feet). Then the decline of the forest began. About 4,000 years ago, the climate became colder and wetter. At the higher levels, trees could no longer thrive. At all levels peat developed preventing the growth of seedlings to replace the old trees as they died. Today one can find old tree roots on the hills, above the present tree line of about 350 metres (1,000 feet) and in the peat bogs.
On Loch Maree we can some of the remnants of this Great Wood of Caledon. On the north facing slopes is the National Nature Reserve with its Scots pine. Opposite on the favourable lower south facing slopes are the oaks. Both are interspersed with birch. On low wet areas grow willow and alder.
Britain has a climate which leads to the climax vegetation of the North Temperate Forest Zone, stretching round the globe. With the flooding of the land now covered by the North Sea and the English Channel, not all the trees of this forest zone reached Scotland. Spruce and larch, both of which grow well and regenerate naturally here, were introduced by man from Europe. They would have been natives but for the sea barrier.
About the time the forest reached its climax, man arrived in Britain, migrating from the continent, both across the English Channel, and up the western seaboard. At first man subsisted by hunting and gathering food. Then he learned to grow his own, with crops in the fields, and animals grazing in the forest. Trees were cleared for farms, and livestock ate young seedlings, preventing the replacement of the old trees.
By Roman times, perhaps half the forest was no more.
Bythe seventeenth century, the ironmasters of Lancashire and Cumbria were looking for new supplies of charcoal for their furnaces, having exhausted local supplies. They brought their ore north by sea for smelting, using charcoal from Highland forests. Thousands of acres were cleared. In the south too, timber was required in ever growing quantities. Until overseas trade developed in the eighteenth and nineteenth centuries the native forest was to provide what was required. Forests were reduced to 4% of the total area of Scotland.
It was not all destruction. In the eighteenth century great estates vied with each other to plant trees, notably Seafield, Atholl and Argyll. In 1919 the Forestry Commision commenced its operations. Two world wars set things back. By 1947 only 3% of the land was populated by trees.
Since 1945 the State and private owners have at last been platngin on a scale to redress the balance. About 10% of the land of the Highlands is now covered with trees.
West and south of Lochcarron are the Commission forests of North and South Strome, and towards Achnasheen is Achnashellach. To the east of the Smithy is the privately owned forest of New Kelso.
Much of this new planting was carried out mainly with commercial objectives, but on bare hills and forest growth is an advantage. Populations of animals and birds have increased in both quantity and variety. Native bushes and trees have been favoured by the shelter of the spruces and larches. And most foresters are keen to encourage the native pinewoods within the commercial forest.
Today encouraging the extension of native pinewoods is in fashion; work is going on to extend a remnant of the old pinewoods at Achnashellach, alongside the continuing production of timber on a commercial scale.
( photographs by Vicky Stonebridge)