Fungi and lichens in Glen Cannich

In early December I decided to go to Glen Cannich for a day of photography. It was quite a while since I’d been into that glen, and as I like to vary my destinations for each trip, it seemed like a good choice for a different location to where I’d been recently. With the daylight hours being very short at this time of year, as we approach the mid-winter solstice, I opted to stay close to the road, and visit a part of the glen I’d not explored before.

This is an area of the river where it forms the boundary between land owned by Forestry Commission Scotland on the south side and a private landowner to the north, just west of the road bridge that crosses the river. I’d been on the north side there previously, where there is a stand of aspen trees (Populus tremula) and some old Scots pines (Pinus sylvestris), but I’d never taken the time to explore the south side before.

This is due in part to the fact that there had formerly been commercial plantations of non-native conifers there, underplanted around and between the remnant native pines of the Caledonian Forest. However, the non-natives had been removed some years ago, and a new generation of Scots pines and birches (Betula pendula and Betula pubescens) are springing up there now, because of the reduction in numbers of red deer (Cervus elaphus) and the overgrazing that formerly occurred in the area.

In particular, there are some fine-looking old Scots pines beside the river on the south side, and they were my destination for the day, including some that are on a small, mainly rocky island in between two channels of the Cannich River. Before I reached the first of the pines, my attention was drawn by some small bright orange fungi growing out of some dead wood on the ground. These were the small stagshorn fungus (Calocera cornea), and nearby I found a cluster of a closely-related species, the yellow stagshorn fungus (Calocera viscosa) amongst pine needles near the base of one of the old pines. This species, unlike, the small stagshorn, has branched, or birfurcated, fruiting bodies, and is slightly larger in size.

Near the small stagshorn fungi, another piece of dead wood embedded in the ground was the host for a nice colony of a distinctive lichen (Icmadophila ericetorum). This is a northern species that in Britain is only common in Scotland, where it grows on peat banks and rotted conifer wood and old stumps, typically of Scots pine in the Caledonian Forest. This lichen also occurs in Scandinavia and North America, where it is known as candy lichen, or less favourably, as fairy puke lichen.

These common names are derived from the lichen’s physical appearance, in which the grey-green colour of the thallus (the main part of the lichen) is peppered with pale pinkish-orange discs. These are the apothecia, the structures that release the spores of the fungal partner, which together with an alga, make up the symbiotic or combined organism that we know as a lichen. Different lichens have varied apothecia, some of them being inconspicuous, and as it turned out I ended up photographing three quite different types during the day.

There doesn’t appear to be a common name for this lichen in Britain, which adds to a problem I’ve encountered before – the fact that although species like this are quite easy to identify, I can’t easily remember its name, because the only name it has is the scientific one, which is complicated, long and difficult to pronounce. In recent years, ecologists in the UK have gone to some lengths to give common names to large numbers of the fungi and mosses that occur here, and the same needs to be done now for lichens, in my view.

While I was photographing this lichen, I noticed some movement amongst the heather (Calluna vulgaris) next to the dead wood it was on. Turning to get a closer look, I was surprised to see a small micro-moth fluttering there, and as I watched it settled on a rock next to the heather. My surprise came from the fact that it was early December, and invertebrates in general were nowhere to be seen, having all gone into pupation or dormancy for the winter. I sent the photograph of this micro-moth to Bob Heckford, a specialist who helps me with the identification of micros, and he replied that it was either Acleris notana or Acleris ferrugana  – two very closely related species that are almost impossible to tell apart without dissecting a specimen. This particular moth was spared that fate because it moved again into the thick vegetation and I lost it. Bob thought that, based on the habitat there, it is more likely to be Acleris notana, hence the ‘probable’ caption to my photograph here.

Moving on a little further, I crossed the smaller, southern section of the Cannich River, in order to explore the island which is formed by the two branches of the river. It was quite a wet, overcast day, and I was having trouble keeping the lens on my camera dry, so I wandered around during the heaviest of the rain without my camera. I noted a few subjects of interest, and when the rain relented a bit, I returned to them to take some photographs.

 

One of the features that attracted me was a birch tree with twin trunks, both of which were dead. The trunks were leaning at an angle to each other, and they had bracket fungi fruiting on them, but these were of two different species, one on each trunk. On one it was the common tinder fungus (Fomes fomentarius), while on the other it was a much scarcer species (Phellinus lundellii), which I’ve previously photographed elsewhere in Glen Cannich.

I was particularly pleased to see this scarcer bracket fungus, and although I’ve found it at Dundreggan and in Glen Strathfarrar, Glen Cannich seems to be a particular stronghold for this species – I’ve photographed it there with a different white fungus (Cladobotryum varium) growing on it. According to Liz Holden, the mycologist who helps me with fungal identifications, this species has not been well studied in terms of its taxonomy, and there may be more than one species labelled with this name in the Highlands. I’m hoping to get Liz out to look at where it occurs in Glen Cannich at some stage, to see if she can tease out the actual identity of the various different examples of it that I’ve found.

 

 

 

 

 

 

 

 

 

Because of the near constant rain, the upper surfaces of these bracket fungi were dark and shiny, providing a vivid contrast with the lighter pores on the underside, which release the spores that enable the fungus to reproduce.

While I was photographing these fungi, I noticed something else of interest at the base of the birch tree. This was some dog lichen (Peltigera hymenina), and it was also dark and shiny from the rain, with contrasting reddish-brown apothecia on many of the lobes of the thallus.

 

 

 

 

 

 

 

 

 

 

 

 

 

These apothecia are quite different in shape to those I’d seen on the other lichen earlier. Another distinctive feature of this dog lichen is the presence of rhizines. These are white spiky structures on the underside of the thallus that are root-like and perform the function of attaching the lichen to its substrate.

Blustery showers were a regular feature of the day, so during the periods of rain, when I couldn’t keep the camera lens dry enough to take photographs, I wandered around, looking for other things of interest in the woodland. On a nearby birch tree I found a very nice patch of another common lichen – cudbear lichen  (Ochrolechia tartarea). This is a crustose lichen, meaning that the thallus grows flush against the substrate (the birch trunk in this case), and it is pale greyish-white in colour.

Cudbear lichen has some of the most distinctive of all apothecia, and these take the form of pale brown discs with white rims that can occur at a high density on the lichen thallus.

 

 

 

 

 

 

 

I also found a number of other different lichens with apothecia on them, but the rain and then later the fading light preventing me from getting any photos of them. I did find a very bright orange crustose lichen on a rock, but when I sent a photo of it to John Douglass, a lichenologist who helps me with identifications, he said it was impossible to tell from the image alone whether it was a species of Porpidea or Lecidea – two genera which both have orange species like this in them.

Although it was only 2 pm, the overcast conditions meant that it was twilight already, and the opportunities for photography were coming to an end. However, I did find one last thing of interest, on a small fallen branch of a rowan tree (Sorbus aucuparia). I was quite excited as it looked like a slime mould – one of my favourite types of organism in the forest – but this was not one that I recognised. In the fading light I had to use the flash with my macro lens to be able to take these photographs of it.

I emailed the photos to Bruce Ing, the UK’s leading expert on slime moulds, but haven’t heard back from him yet about them. I also collected a couple of sections of it as specimens, and I hope that, between the images and the samples, I’ll be able to get it identified. This was an intriguing end to my day there, and it was one in which my opportunities for photography had been considerably restricted because of the wet and windy conditions and low light levels. Nevertheless, I felt like I made the most of the day, although I didn’t see much of this pinewood area on the south side of the Cannich River – I’ll have to return another time to continue my explorations there.