I was up on Arkle last week, a mountain in the the north-west Highlands. This is a land of complex geology and marvellous landforms. The hill is topped by 500 million year old quartzite, laid down in shallow seas.
Now it is 250m above sea level and forms a hard stony surface, breaking down into screes and coarse nutrient-poor soils - a desert like place.
Few plants can gain hold and find a niche to live on these wind-scoured tops, but here a single bud of Thrift comes into bloom amongst the sharp rocks.
Water has collected on part of the lower plateau forming a lochan which shines blue in the white landscape, due to the nutrient poor water and few plants or animal life that can live in it.
