Category: Lichen

Continuing my theme of upland lichens, Caz Walker and I visited Little Dun Fell in the Pennines on 7/6/21 hoping to acquaint ourselves with the arctic-alpine species that have been found there, as well as to see how they are doing. We approached from a friends’ house in Eden valley fellside, so quite a trek with 11 miles total and 600m of ascent!  We saw a ring-tail hen harrier on the way up, along with a couple of curlews and golden plover, though perhaps there should have been more. There weren’t very many flowers but a red admiral butterfly perched on the rocks at the summit of Little Dun Fell (which is just inside the Moor House NNR). The boulders also hid several bits of flotsam including two fluorescent rucksack waterproof covers and that not so rare species Plastic pepsicola.

Little Dun Fell, Great Dun Fell and Cross Fell are on the Pennine Way in Cumbria with tops at over 840m: a layer of hard acidic gritstone, interbedded with other sedimentary rocks, showing as outcrops on the sides of Cross Fell and a boulder field just to the north of the summit of Little Dun Fell.  Great Dun Fell sports a “golf ball” radar station – a landmark visible from afar on the west, and looks like a modern art installation close up.

The altitude and geology of these windswept tops provides a suitable home for various arctic-alpine lichen species that are more usually found on the tops of Scottish hills. Most of the lichen records are from some time ago, though Allan Pentecost visited Cross Fell summit in 2016.  The last lichen records for Little Dun Fell in the British Lichen Society database are from 1979 at a BLS field trip which spent a week in the Penrith area (1). Some notable records have a 6 figure grid reference while others just have a hectad reference.  

Caz had seen a few of the target species on trips in Scotland with the BLS montane group. We should also recognise other montane specialists that we’ve seen in the Lake District fells.  We made a good list of species, re-finding some of the rarities and adding one more.  However, Umbilicaria proboscidea was missing, having been described as locally frequent at Little Dun Fell in 1979. We also didn’t see Arctoparmelia incurva which had been present then, but we could have missed it this time.

We re-found nationally scarce Allantoparmelia alpicola on quite a few boulders – tiny contorted and convex lobes.  In addition we found two small appressed species that look a bit like Cetrarias.  Cetrariella commixta was there previously, but Melanelia hepatizon is new for this top, though found west of Cross Fell in 1990 by Simon Davey.  The M. hepatizon had pseudocyphellae on the lobe margins and the surface of the thallus; not present on the upper cortex of the C. commixta. More definitively, in M. hepatizon the white medulla is K+ yellow while in C. commixta it is K-. Note that the algal layer will turn greeny yellow during the test.

We also found Parmeliopsis ambigua on a boulder. This is mainly on acid barked trees, but it was found here in 1979 and there are a few other saxicolous records for Cumbria, with some of these on headstones in graveyards. It is yellow grey with globose soralia testing yellow with K.  We wanted this to be Arctoparmelia incurva but that is KC+ pink and has different shaped lobes.

Schaereria cinereorufa was also present, with the uniseriate globose spores confirming it later.

In the turf, slightly surprisingly, was good old Bilimbia sabuletorum which we wouldn’t expect in an acid environment. However there is basic rock in the area.

Fifty metres closer to the actual summit there are two fenced exclosures, erected in 1954.  The 1979 BLS trip report says that these had taller vegetation inside, with Cetraria islandica and Cladonia arbuscula having increased their cover to form large cushions. The exclosures are still there with intact fences, but we saw neither of those species in a quick look, though we did see Cladonia ciliata.  The inside vegetation is indeed slightly taller, but not a lot, so the extremes of weather do stop dominant species even with no grazing or trampling. I don’t think the two lost species were present outside of the exclosures in 1979, presumably due to grazing or historic burning. But any chance of recolonisation now seems to have gone. Update: We did see Cetraria islandica on a later visit to nearby Great Dun Fell and Cross Fell.

There’s a similar old exclosure at Cow Green Reservoir (also in Moor House NNR) that we visited on 29/7/20. The growth there was similarly slightly higher inside, and had bushy C. islandica along with Common twayblade and Cloudberry.  So, it feels like the Little Dun Fell exclosures aren’t doing very well, even with grazers excluded.  A long term study of the Moor House vegetation plots, 2015 (3), says that “during the period that Moor House has been protected as a nature reserve the vegetation quality has declined in spite of reductions in grazing pressure.”  The study reports Little Dun Fell as having the highest numbers of sheep (at 5.8 per hectare average between 1954 -1998) but says that “overall, removal of sheep grazing had few positive effects and many negative ones”. It doesn’t reach any definitive conclusion as to what’s going on but speculates that “it is possible that this reflects a continuing late-twentieth century impact of  atmospheric pollution”. Increased temperatures from climate change won’t help. 

That report also says, “What is of particular concern are the reductions in the probability of occurrence of liverworts and lichens.”  “Biotic homogenisation has now been detected in Great Britain at the countrywide-scale (Smart et al. 2006) and within alpine communities (Britton et al. 2009 (4)), and it is possible that this reflects a continuing late-twentieth century impact of atmospheric pollution”. A paper from Mitchell in 2017 (6) echoes these findings: less specialist species are invading the highest refuges for alpine species of various taxa. The combination of warming and nutrient loads in most uplands is therefore reducing biodiversity.

It would be good to check out more of these Pennine tops to get a better overview of the situation, so, as usual, a repeat visit is required, ideally with less of a walk-in.  In particular it would be lovely to check the only English record of Umbilicaria hyperborea on Cross Fell, in the database for 1979 following its finding by Rod Corner in 1977 (2).

Re-finding existing records is great to build up your knowledge – and check the state of play on the ground. The distribution lichen maps for Cumbria are online here, and I can provide full records –  and the BLS records officer is happy to provide database snapshots for other parts of the country. It’s also good to visit new areas – and thinking about the geology and vegetation can suggest where to look.

Chris Cant

1. Coppins & Gilbert (1981). Field Meeting near Penrith. Lichenologist 13(2): p193
2. Corner (1978). Umbilicaria hyperborea discovered in England. Lichenologist 10: p134
3. Milligan, Rose & Marrs (2015). Winners and losers in a long-term study of vegetation change at Moor House NNR: Effects of sheep grazing and its removal on British upland vegetation.
   https://core.ac.uk/download/pdf/82709587.pdf
4. Britton et al (2009) Biological Conservation 142/8 p1728-1739
   Biodiversity gains and losses: Evidence for homogenisation of Scottish alpine vegetation
   https://www.sciencedirect.com/science/article/abs/pii/S0006320709001451
5. Britton et al (2016)
   Climate, pollution and grazing drive long-term change in moorland habitats
   https://onlinelibrary.wiley.com/doi/abs/10.1111/avsc.12260
6. Mitchell et al (2017). Biological Conservation 212 p327-336
   Forty years of change in Scottish grassland vegetation: Increased richness, decreased diversity and increased dominance
   https://www.sciencedirect.com/science/article/abs/pii/S0006320716310722

Many of the lichens you see up on the fells are hard to tell apart. But one that is easy to identify is Ophoparma ventosa, the blood spot lichen. Once you’ve seen it, you’ll remember it. And you might not even need a hand lens!

It’s a crusty, cracked and rough (sometimes warty) splodge on the rocks with big (up to about 3mm!), flat, red fruiting bodies (apothecia to give them their proper name) that stand out from quite a distance. They look like blood spots: sometimes dried blood, sometimes a bit fresher.  Young fruits can have a paler margin.

Funnily enough, there are two different types of Ophioparma ventosa, which can be found next to each other if you’re lucky. One has a grey coloured thallus (main body of the lichen) with a bit of a pinky tinge, the other is a yellowy-grey. The difference is that the yellow one contains Usnic acid (which gives it the colour). 

If you’re in any doubt about whether it’s Ophioparma, you can put some K (caustic soda) on it: the thallus goes a yellow-orange colour, the apothecia a purplish-blue.

You’ll find it on rough-grained acid rocks (boulders, outcrops, cliffs and walls) across Cumbria: British Lichen Society records show it from the Duddon Valley; near Beetham; towards Tan Hill and in Bowness on Solway as well as on the Lake District Fells, where it’s most common. But, at the time of looking, there were only 68 records across the county.

The distribution seems really patchy. Sometimes you see loads of it: on a recent day up one side of Red Screes it seemed to be on almost every rock. But then a few days later, on the other side of Red Screes, I didn’t find any at all. The difference is probably to do with rock type.

If you look at Ophioparma ventosa very carefully through a hand lens, you’ll maybe see some black blobs on the surface as well. Now sometimes these are the lichen’s pycnidia, from where asexual spores are released. But they might also be a lichenicolous fungus called Muellerella ventosicola. This has recently been seen for the first time in England (Devon) and was then found almost immediately in Cumbria. I haven’t yet found it myself, but I’ve started looking at the black dots just a bit more closely!

We’d like to know more about where Ophioparma ventosa is in Cumbria. Next time you see some, take a photo on your phone, grab a grid reference for it (https://gridreferencefinder.com/) …and then let us know! Together we can track the blood spots!

There are many lichen habitats in Cumbria, some literally on your doorstep. However, if you want a walk then there’s potentially lots to see while out on the fells and scars of the Lake District and the Pennines. The species I’m showing here don’t need a hand lens to see. With your eye in, you can spot them en route. If you have time and a sunny day or flask, then do take a breather and stop to have a closer look. If you are more adventurous, do visit ghylls, crags and the spoil heaps outside old mine-workings – but do take care.

Most lichen species have a preference for either acid or basic geology with some only found high up on montane heaths. Just as we look at geological maps to see what lichens are around, geologists have been known to look at the lichens to determine the rock type!

Limestone scars and pavements

Limestone is a basic (alkaline) rock which forms outcrops called scars – and flat pavements of clints (stones) and grykes (the gaps between). Limestone pavements can be great for specialised plants. In the past stone may have been robbed out but many areas are now protected.

Many of the limestone specialist lichens are crusts which can be hard to identify. On our local patch, Knipe Scar, there’s lots of Squamarina cartilaginea with green squamules .  If you look carefully you might see Solorina saccata on the vertical sides of the clints. It’s easy to see why this species has a common name of Chocolate chip lichen. On our local patch, Knipe Scar, I’ve taken photos six months apart; you can see the brown fruit less developed in one area in the inset photo.

On the short turf beside the pavement, you might find Peltigera leucophlebia or ‘fleb’ as we’ve come to call it, usually with green lobes with small black warts on. There is a similar green lichen P. britannica but this is rarer and not on basic rock; we have re-found this species at a couple of sites in the Lakes.

Fell lichens

The geology of Cumbria can be pretty complicated, but most of the fells are acidic /siliceous / volcanic rock. There are still plenty of places with basic flushes, so you might find Peltigera leucophlebia for example amongst the crags. And vice-versa, you can find erratic siliceous boulders on limestone.

If you look on the rocks around you, you will often see Stereocaulon vesuvianum, looking a bit like a mini-eruption from Mount Vesuvius, or map lichen Rhizocarpon geographicum usually looking yellow/green with black borders between the ‘countries’. Another common species is Parmelia saxatilis. Some species found on trees are also on montane rocks as well as heather, eg Platismatia glauca and Hypogymnia physodes.

On some rocks you might find Lasallia pustulata which is one of the species called ‘rock tripe’ which I’m told is edible – I’ve never tried it but it does look a bit like a poppadom! This is whitish-grey when dry but is green when wet, which got me very perplexed once.

Ophioparma ventosa, blood-spot lichen, is fairly common on acid rock, with the main thallus either yellow-ish or pale pink. The red fruit are lecanorine, which means the pale thallus forms the exciple margin of the apothecium, providing a jam-tart-in-pastry look.

Another genus you might find is Sphaerophorus with species S. fragilis and S. globosus found in Cumbria, both with a coral like appearance, occasionally found with black eyed stalk fruit, but often grazed by slugs!

As you get a bit higher, on rocks you might see various Umbilicaria species such as Umbilicaria cylindrica. If fertile these have amazing gyrose fruit ie with spiral patterns. U. cylindrica is usually gray with prongs on the margins. The rarer U. polyrrhiza is a lovely pale chocolate brown with a mass of black rhizines underneath. In Langdale there is the main site in the UK of nationally rare Umbilicaria crustulosa.

Also higher up, but usually quite small, is the lovely Cornicularia normoerica.

Montane heath lichens

The tops of the Lake District fells and some parts of the Pennines have harsh conditions that resemble the arctic. Here, the heather and grass don’t grow very tall as they are lashed by the wind and rain. Where you see the nets of Cladonia portentosa and tubes of Cladonia uncialis you are in the right sort of area. Sometimes these species can be found lower down, alongside Cetraria aculeata.

This ‘wind-clipped heath’ on the fell tops is a precious habitat so if you find it, don’t trample around too much.  Species that do well in more northerly latitudes can be found here, such as Thamnolia vermicularis, Cetraria islandica and Ochrolechia frigida. Our map for Thamnolia shows the sort of places you can look, but new sites are still being found in the Northern fells. Recently I found a loose fragment of C. islandica on the top of High Street in the eastern fells, possibly pulled up by a corvid. This would be a new site – but exploring at the time and on a subsequent visit, we couldn’t find where it came from.

Text and photos by Chris Cant

• 56,980 lichen records from 1805 to January 2020
• Some are rare and internationally important
• Join the Cumbria Lichen and Bryophyte Group

• Lichens are long-lived and important indicators of biological continuity.
• Lichens grow on live bark, dead wood, soil and rock. Habitats include woods, dunes, parkland, becks, gates, dry-stone walls, fences, gravestones, mine spoil and pavements.
• Lichens need water and light to photosynthesise – eg look on sunny, south-facing aspects for Lobaria pulmonaria.
• Cumbria has a varied geology with ecological niches to accommodate almost all lichens, eg some lichens prefer base-rich rocks such as limestone and can be found in basic flushes on hills.
• The Lake District has important remnant Atlantic woodlands, also known as temperate rainforests, which are found in western Britain due to the oceanic climate eg in Borrowdale and Ullswater valleys.
• Tree bark pH indicates likely species: ash and elm are more basic; oak, birch and pine are more acidic.
• The fells are an important montane habitat in the Lake District and Pennines, with many inaccessible ghylls and crags, an under-recorded habitat.
• Lichens are sensitive to changes in their surrounding environment. In Cumbria, over time, composition and diversity has been impacted by air pollution (acidification/nutrient enrichment), habitat loss, invasive species (native/non-native) and unfavourable woodland management.

Data from British Lichen Society, Natural England, British Geological Society, Ordnance Survey and others – thanks. Maps made using QGIS.

First published in the British Lichen Society Bulletin.

Caz Walker and I ‘discovered’ lichens last year. First, Caz volunteered to be trained up as a lichenologist in the New Generation Botanist scheme, part of the Plantlife ‘Looking Out for the Small Things’ project which was particularly looking at the Atlantic woodlands of the Lake District and Cumbria. Then I was drawn in to this exciting (small) world, opening my eyes to new features of places I thought I knew, and helping us find places to explore that we’d by-passed before.

We live on the edge of the Lake District within easy reach of Haweswater – the area includes quite a lot of geology, ie different rock types, with Umbilicaria and Massalongia carnosa amongst others to be found on the fells. Beside Haweswater are the old-ish woods at Naddle Forest and Mirkside which seem to be the easternmost remaining patches of temperate rainforest with species such as Lobaria pulmonaria and Bunodophoron melanocarpum.

However our local patch is Knipe Scar, common land north-west of Shap, a heavily grazed limestone fell with areas of limestone pavement. Looking up the NBN Atlas, Caz found that the only lichen records were six figure grid references for Peltigera leucophlebia, recorded by local lichenologist David Clarke. Eventually we spotted some and, once we got our eye in, found quite a few more patches in short grass in thin soil over rock.

On 15^th June 2019, Caz found a patch of P. leucophlebia that was fertile, which we understand is rare in the UK and probably a first for Cumbria. On the following day, further patches were found close by, starting at NY5414118479 ie in the southern section, next to Shapbeck Quarry. David Clarke visited and confirmed the sighting a few days later.  To our knowledge, no other fertile colonies have been seen elsewhere this year to date.

P. leucophlebia is green with dark wart-like cephalodia on its upper surface, and distinct veins and dark rhizines on the underside, paler towards the margin.  The first fertile instance had a few apothecia; subsequent patches had multiple fertile lobes. When fertile, P. leucophlebia has red-brown apothecia on the upper surface of tongue-like lobe-ends. In the examples found, the lobes were strongly recurved, revealing characteristic green corticate patches on their undersides and concealing the apothecia. The apothecia themselves were round to oblong with smooth to crenulated margins.

We’ve been recording lichen sightings and even managed to submit some spreadsheets. The ‘coincidence map’ of records for Cumbria shows that it is mostly blank space ie no records for most monads – a lot of work to do!  Hopefully our records will literally get lichens on the map and encourage others to find what’s there. Chris Cant