(the picture above shows mature downy birch trees with a ground cover of heather and dwarf birch)
This last weekend we were in the Western Highlands – on the Ardnamurchan Peninsula to be precise – the home of ancient Atlantic rainforests, heather, wild, rocky moors and spectacular mountains – one of the most remote parts of the UK. Spring is late coming; there is still snow on the higher peaks in Glen Coe and elsewhere, and it has been cool and wet. Downy birch trees and honeysuckle, some hawthorns too, are just in leaf and you can see blackthorn blossom here and there. Against the dun browns, oranges and purples of the moors, bright yellow gorse flowers are an acrylic highlight. Walking up a glen by a rushing burn we heard our first cuckoo of the year. And then among the scrubby vegetation we saw the orangey spikes of dwarf birch catkins, poking up erect from spiky twigs and looking for all the world like mealworms; so I had to stop to get a few pictures of this special plant. The leaves won’t be out for a while longer – so this is a good time of year to notice one of nature’s more modest gems.
The dwarf birch (Betula nana) was possibly the first tree to colonise the British tundra after the last Ice Age ended some 12,000 years ago. Its flowers (male and female on the same tree) are pollenated by the wind; and that’s also how it’s tiny, very light seeds are distributed. It hugs the ground, binding thin soil and peat and providing cover for the first birds and mammals to follow behind. It also supports a range of insects and their larvae, and is connected below ground with mychorrizal fungi – so it’s a key player in these fragile ecosystems. It provides grazing for deer and sheep and that’s partly why it is not such a common sight these days – both mammals are overstocked. Here on the shores of Loch Sunart, many areas are being fenced off and allowed to grow back to their natural habitat. When the bigger trees come into leaf – oaks, downy birch, rowan – the dwarf birch will retreat modestly from view; but it’s a special native, to be cherished.