The first snow of winter

On the 11th and 12th of December the first substantial snow of the winter this year fell in the Highlands. November had been a remarkably mild month, and this continued into the early part of December, so the change in the weather was quite dramatic. Because of Scotland’s maritime climate, snow often doesn’t last for long, and our frequent winds can remove it from the trees within hours, so I knew I had to seize the moment, so to speak. Thus, to take advantage of the pristine white conditions, I headed out to Glen Affric the next day, on Saturday the 13th. 

Along the route to the glen, the snow was surprisingly intermittent, with some areas having lots and others almost none at all, so I was slightly apprehensive as to whether there would be much in Affric when I got there. However, I needn’t have been concerned as I arrived in the glen to find a winter wonderland, with snow still on all the trees, particularly in the sheltered area of the Affric River gorge between Badger Falls and Dog Falls. The sun hardly reaches there in the winter, and the narrow confines of the gorge offers some protection from the wind, so every tree still had its trunk and branches outlined with a layer of snow, making it ideal for photography.

The multiple stems of the hazels (Corylus avellana) were particularly highlighted by the snow, so I spent a while with them. Remarkably, one young hazel sapling still had some leaves on it, and they were green even, making a vivid contrast with the white landscape everywhere around it. This seemed quite astonishing to me, as the hazels generally lose their leaves in October, but somehow these had persisted for another 6 weeks at least.

This also reminded me that 2014 was a very abundant year for catkins on hazels in the early spring, with some appearing as early as 8th January at the north end of Loch Ness. This lengthening of the growing season for hazel at both ends of the year is definitely unusual and I wonder if it’s a consequence of global warming, caused by the ever increasing amounts of carbon dioxide that humanity is pumping into the atmosphere? I’ll be interested to see if catkins appear as early again in 2015 …

None of the larger, mature hazels had any leaves left on them, so I wondered if this phenomenon was due to some special characteristic of very young hazels? Saplings of other trees, such as oak (Quercus petraea) and beech (Fagus sylvatica), can retain their leaves (albeit brown and dried) through the winter when they are young, so perhaps this is an attribute of hazel as well, that I haven’t come across before.

Some of the hazels had branches or stems that were leaning out almost horizontally, reaching for the light in the gap in the canopy where the road is. Abundant lichens flourish on these stems, sustained by the constant moisture and humidity in the atmosphere there, due to the spray from the cascading water of the Affric River in the narrow confines of the gorge. These lichens also provided a wider platform for the falling snow to rest on, so they were almost invisible underneath the white blanket that the weather had draped over them.

In humid locations like this in the Caledonian Forest, lichens like these can completely cover the branches of trees, and are particularly noticeable on wet days (with no snow) in winter. They usually consist of a number of common species, including those visible under the snow in this image – ragged lichen (Platismatia glauca), beard lichen (Usnea filipendula) and heather-rags lichen (Hypogymnia physodes).

Walking along the road a little, my attention was drawn by a young Scots pine (Pinus sylvestris), in amongst a group of birch trees, just below the road. While I was looking at it, though, the branches of the tree next to it drew my eye, as they had fruits on them. Initially I thought that they must be hazelnuts that had somehow stayed on a tree for much longer than usual. However, when I looked more closely I saw they were in fact red berries, and that this was a hawthorn tree (Crataegus monogyna), and one that I hadn’t previously been aware of as growing in this location.

 

 

 

 

 

 

 

As with the leaves on the hazel sapling earlier, I was surprised to see these berries still on the hawthorn’s branches, as they usually all get eaten by birds, or fall off, in October. However, if it hadn’t been for the berries I would never have realised that this was a hawthorn, so I was glad that they were still there this late in the year.

Turning back to the pine, I took a few moments to appreciate it, as there aren’t many pines on this north side of the Affric River, between Badger Falls and Dog Falls. The trees there are mostly hazel, birch and rowan (Sorbus aucuparia), with smaller numbers of aspen (Populus tremula), oak (Quercus petraea), eared willow (Salix aurita) and goat willow (Salix caprea). Scots pines predominate on the south side of the river, both here and further west in much of the glen, where the north-facing aspect seems to suit them better.

This area, between Badger Falls and Dog Falls, and on the north side of the Affric River, is the richest part of Glen Affric in terms of its tree species, as there are also a couple of wych elms (Ulmus glabra) and ash trees (Fraxinus excelsior) there as well. All of these scarcer species were probably more abundant in the past, as there are suitable soil conditions along much of the north side of Loch Beinn a’Mheadhoin, but I suspect they were lost due to past deforestation, and then were unable to regenerate because of overgrazing by red deer (Cervus elaphus).

Now, because of the lack of a seed source, there are very few young trees from those species further west in the glen, where birches (and occasionally pines) predominate.

 

 

 

 

 

 

 

I noticed this again as I drove further west, especially when I stopped on the north side of Loch Beinn a’Mheadhoin, a few hundred metres west of the dam. There’s a large, rocky headland there that provides shelter from the prevailing westerly winds, and from the low-angled winter sun, so the trees there were all still covered in snow as well. I’ve long been aware of this area, and the micro-climate that is created by the topography there – the trees are covered in lichens, and, closer to the ground, by an abundance of mosses, forming a small pocket of temperate rainforest in the glen.

The trees are mostly birches, with occasional rowans and some alders (Alnus glutinosa) along a small burn that flows into the loch. There’s a single goat willow and a few pines on the higher ground, but it’s the birches that are most abundant, and the older ones are heavily-laden with lichens. Today, with the snow delineating every branch and providing a white backdrop, the lichens seemed especially prominent, and formed an almost fairytale-like landscape – a winter wonderland of delicate snow-covered trees.

In the wind-still conditions, the catenaries formed by the beard lichens seemed particularly elegant and graceful, and looked almost like they were diminutive figures in pale green robes brachiating between the branches of the tree. The stillness in the air was palpable and conveyed to me some of the most special feelings of the depths of winter, leaving me in awe once again about the elemental ability of Nature to completely transform a landscape through the simple act of snow falling.

Everywhere I looked there was an elegance to the shape of the birches, and it was very apparent that the older trees were carrying substantially greater loads of the lichens than the young ones were. This illustrates the importance of mature or old growth forests, as they support a different range of species, and in many cases a greater abundance as well, than young forests do. We’re fortunate at present to still have these old remnants of the Caledonian Forest in Scotland.

For the Scots pines in particular, and to a lesser extent the birches, there is a looming problem caused by the existing generation gap, when the mature trees will die of old age in the coming decades. There will be no middle-aged trees to replace them, because of the 200 year period when no young trees were able to get established, due to overgrazing by the deer. In Affric, there are pines and birches now that are 50 years old, dating from when regeneration measures were first initiated in the 1960s, but the absence of trees in the 50-250 age range means that old-growth dependent species will struggle to survive when all the current old trees have died.

 

 

 

 

 

 

 

The beauty of the forest on this snowy day was what touched me though, not the coming absence of old trees, and everywhere I looked the snow had created stunning natural works of art.

As the day was overcast, the landscape was almost entirely black and white, and it was only the occasional patch of moss, as on this rowan tree here, that brought some different colours to the forest.

 

 

 

 

 

 

Soon, the daylight was beginning to fade, as it was less than two weeks to the solstice, so I didn’t have an opportunity to visit any other parts of the glen this day. However, I headed for home well-satisfied with this encounter with winter in the forest.

 

 

 

 

 

 

 

During the day, I’d been shooting some video footage as I went along, so here’s a short compilation to finish the blog with:

https://www.youtube.com/watch?v=zG66ShpRKfI;vq=hd720&rel=0&showinfo=0