I never saw the ‘face’ at the time of taking this photograph. It wasn’t until I got it on the PC screen that it was there in profile with its pointed chin, blunted nose and dark staring eye. Apart from looking like a face it is Hammered Shield Lichen (Parmelia sulcata) growing on a rotting branch.
April 2018, local woodland margin, Staffordshire, England. © Pete Hillman
Golden Shield Lichen (Xanthoria parietina) is a lichen which is very hard to miss, such is its bright colour.
March 2017, local wood, Staffordshire. © Pete Hillman 2017. Camera used Nikon D7200 with Sigma 105mm macro lens.
Back from the weekly shop and there has been a break in the clouds. Barely packed away and I have my camera in hand. I love seeing how the rain enlivens and refreshes everything, it is just my thing 🙂 An odd title for this post I know, but this patch of green just off my front driveway measures around 4×2 inches (100x50mm). I am like a little kid again seeing things for the first time, wide-eyed and full of amazement at how wonderful and beautiful nature is, and I hope I never lose this feeling of wonderment and magic.
At worm’s eye view I can see at least four different species of moss, and maybe two species of lichen (please click the image for higher quality). All this within about 8 square inches, and growing on concrete. We pass by so much each day of our lives without always seeing what is write under our noses, and I am as guilty as many for this. It is so nice just to be able to stop the wheel of modern living even just for a few revolutions, or even just to slow it down a little, and focus our senses and minds on something that has been there all along, and to enjoy it!
Photograph of Hammered Shield Lichen (Parmelia sulcata) taken December 2016, local field margin, Staffordshire. © Pete Hillman 2016. Camera used Nikon D7200, with Sigma 105mm macro lens.
A fine powdery mustard yellow lichen. Apothecia yellow.
Found in nutrient rich areas such a bird perches, silica-rich rocks and calcareous rock, and brick, even trees. Widespread and very common.
Photographs of Common Goldspeck (Candelariella vitellina), taken March 2012 on local canal coping and driveway, Staffordshire. © Pete Hillman 2012. Camera used Panasonic Lumix DMC-FZ38.
A pale greyish to buffish cructose lichen, which is thin to cracked aerolate. Apothecia absent.
Found on silica-rich rock, especially outcrops that get wet and dry out fairly quickly. Locally common and widespread in the north and west.
Photographs of Pertusaria aspergilla, taken March 2012 on local Bunter Sandstone outcrop, Staffordshire. © Pete Hillman 2012. Camera used Panasonic Lumix DMC-FZ38.
A blue-grey to silvery foliose lichen, becoming bronze-tinged as it ages. The lobes have conspicuous white pseudocyphellae which form a fine network. Thallus 4 to 20cm in diameter.
Found on the branches and trunks of trees, only occasionally on rocks. Widespread and common.
Photograph of Hammered Shield Lichen (Parmelia sulcata), taken February 2012 on dead deciduous wood, local wood, Staffordshire. © Pete Hillman 2012. Camera used Panasonic Lumix DMC-FZ38.
Branching out, it forms an encrusting, irregular patch, which is smooth and blue-grey or green-grey to yellowish-green on the upper surface. The tips tend to curl up revealing brown to black undersides. The thallus lobes are tube-like, semi-erect structures which grow from the outer edges and are covered in sordia (reproductive structures). Thallus 6 to 8cm broad.
It grows in a wide range of habitats, and found on twigs and branches, but also on rocks and walls. It can be an indicator of older forest growth. Common and widespread throughout the British Isles.
Photographs of Tube Lichen (Hypogymnia physodes), taken March 2012 on dead deciduous wood, local wood, Staffordshire. © Pete Hillman 2012. Camera used Panasonic Lumix DMC-FZ38
This is a vibrant green lichen when wet, but dull when dry. The podetia (stalk-like growths) are narrow and curved, and tapering to a point or a tiny cup. These can grow up to a height of 3cm.
Found on mossy, decaying tree stumps. Common and widespread throughout.
Photographs of Common Powderhorn (Cladonia coniocraea), taken April 2012 on rotting tree stump, local wood, Staffordshire. © Pete Hillman 2012. Camera used Panasonic Lumix DMC-FZ38.
The bottom image looks a little like a world map of some alien planet rolled out flat, yet this shows Rhizocarpon reductum growing amongst other species of lichen atop an old canal bridge coping stone.
A cructose lichen which is light to dark grey in colour, aereolate forming patches on the substrate. The discs are black with variable flat to pronounced convex surfaces.
Found on silica-rich rocks and old man-made structures. Common and widespread.
Photographs of Rhizocarpon reductum, taken March 2012 on old canal coping stone, Staffordshire. © Pete Hillman 2012. Camera used Panasonic Lumix DMC-FZ38.
This is an off-white or bluish-grey cracked, crustose lichen. Apothecia are rare, but when seen they are tiny with dark steeply convex discs and narrow rims. One or two are found on the areoles.
Often found on rocks where seabirds perch in the splash zone, very rarely on exposed rocks inland. Common and widespread on rocky coasts.
Photographs of Aspicilia leprosescens, taken April 2012, Llandudno, Wales. © Pete Hillman 2012. Camera used Nikon Coolpix P500.
A chalky-white lichen with cracked-aerolate crust with a well-defined margin, which can give it the appearance of a bird dropping. The thallus varies in colour from the above to blue-grey. Apothecia with black discs.
Found on hard limestone often forming large circular patches. Some growths maybe 800 years old. Also found on urban substrates like on concrete and brick walls. Common and widespread.
Photographs of Aspicilia calcarea, taken August 2012, Bournemouth sea wall, Dorset. © Pete Hillman 2012. Camera used Nikon Coolpix P500.
Large -bodied foliose lichen which is pale green, green-yellow to green-grey in colour. It turns grey in shaded areas. It has a rough, corrugated appearance. It has conspicuous course soralia (structure bearing powdery reproductive cells), which mainly inhabits the centre of the thallus (body of the lichen). Apothecia are rare. Thallus 5 to 20cm in diameter.
Found on many substrates, including broadleaved trees, silca-rich rocks, town monuments, fences and roofs. A common and widespread species, although scarcer in central and northern Scotland.
Photographs of Common Greenshield Lichen (Flavoparmelia caperata), taken February 2012 on old Willow, local field, Staffordshire. © Pete Hillman 2012. Camera used Panasonic Lumix DMC-FZ38.
Also called ‘Hooded Rosette Lichen’, it is a grey-green foliose lichen with tiny helmet-like protrusions. It is a good nitrogen indicator. Thallus 2cm in diameter.
Found on tree bark, rocks, stonework and concrete. Common and widespread throughout.
Photograph of Rosette Lichen (Physcia adscendens), taken February 2012 on old Willow, local field, Staffordshire. © Pete Hillman 2012. Camera used Panasonic Lumix DMC-FZ38.
Looking somewhat like dried and caked mud, this lichen can grow up to several cm wide and has shades of olive-green and light brown to dark brown. The thallus is cracked-areolate. Black perthecia (fruiting bodies) are not immersed in the lichen body but sit conical or hemispherical on the areoles.
It occurs on limestone, mortar, concrete, calcareous sandstones, often where there is nutrient enrichment. Widespread and common.
Photograph of Verrucaria macrostoma, taken March 2012 on old canal coping stone, Staffordshire. © Pete Hillman 2012. Camera used Panasonic Lumix DMC-FZ38.
Also called ‘Black Tar Lichen’, it is often confused with oil because of its sooty black nature. It has a regular, almost rectangular areolate pattern. The reproductive bodies are tiny black spots.
It occurs on many types of seashore rock, and is often found above the barnacle zone. It can tolerate sea spray and periodic immersion. Widespread and common on rocky shores around the British Isles.
Photograph of Tar Lichen (Verrucaria maura), taken April 2013, on boulder, Llandudno, Wales. © Pete Hillman 2013. Camera used Nikon Coolpix P500.
The body of this lichens forms yellow to orange neat circles on the substrate, with a pale area inside the outer edge. The centre is often missing, as it often falls out as the lichen matures. Apothecia are common, the discs are a deeper orange with pale margins, packed tightly in the centre of the thallus. Thallus up to 12cm in diameter.
Found on hard calcareous rocks, especially in nutrient rich areas. Also found on walls, old headstones and statues. Common and widespread, especially in the south and east.
Photographs of Caloplaca flavescens, taken June 2012 on stone walls, Bournemouth, Dorset. © Pete Hillman 2012. Camera used Nikon Coolpix P500.
Also called ‘Black-eyed Lichen’, it is a crustose, warty lichen, pale grey in colour with distinctive disc-like black fruiting bodies, each with a raised, pale grey rim. Thallus 10cm in diameter. Fruiting body 3mm wide.
Found well-lit coastal rocks in the splash zone, on seabird perches such as cliffs, and stone walls inland. Rarely found on trees. Common and widespread throughout the British Isles.
Photograph of Black Shields (Tephromela atra), taken June 2012 on sea wall, Llandudno, Wales. © Pete Hillman 2012. Camera used Nikon Coolpix P500
A leprose lichen which ranges from bright green to yellow-green to sulphur yellow in colour. Generally powder thin, but can be thicker in places which cracks. Apothecia rare.
Found in sheltered, dry places on sandstone rock overhangs, dry-stone walls and on man-made stone or brick. Rarely found on bark. Common and widespread throughout Britain.
Photographs of Sulphur Dust Lichen (Psilolechia lucida), taken February 2012 on local Bunter Sandstone outcrop, Staffordshire. © Pete Hillman 2012. Camera used Panasonic Lumix DMC-FZ38.
The body of this blue-grey to greenish lichen is thin and powdery and lacking any lobes or medulla and is composed of tiny granules.
Found in shaded places, on acid rocks, walls, posts, and tree trunks. A widespread and very common species.
Photograph of Dust Lichen (Lepraria incana), taken February 2012 on old Willow, local river, Staffordshire. © Pete Hillman 2012. Camera used Panasonic Lumix DMC-FZ38.
A thick, cructose lichen, cracked-areolate, greenish to grey-yellow in colour. Apothecia initially immersed but eventually emerge, with discs that vary in colour and shape, but mostly greenish or blackish.
Found on nutrient-rich siliceous rocks and walls. It is also parasitic on Tephromela and Lecanora species. Common and widespread.
Photograph of Lecanora sulphurea, taken March 2012 on old canal coping stone, Staffordshire. © Pete Hillman 2012. Camera used Panasonic Lumix DMC-FZ38.
A cructose thallus which is grey-white to pale-grey-green in colour surrounded by a black prothallus. Small apothecia, convex or concave black discs.
An early colonist found on smooth-barked trees. Common and widespread.
Photographs of Lecidella elaeochroma taken February 2014, nature reserve, Staffordshire. © Pete Hillman 2014. Camera used Nikon Coolpix P500.
This foliose lichen comprises of divided, flattened but curled, antler-like branches. Strap-like lobes can vary in colour from greenish-grey above to yellow-grey on the upper surface, whilst it is white below. Green blotches may sometimes be seen on the end of the lobes. Apothecia very rare. Thallus 7 to 10cm long, 1 to 5cm tall.
Found mainly on the branches of oaks and other deciduous trees in sunny areas. Rarely found on conifers. Found in parkland, on wayside trees, and in hedgerows. Widespread and generally common.
Photograph of Oakmoss (Evernia prunastri), taken January 2012, on deciduous wood, local wood, Staffordshire. © Pete Hillman 2012. Camera used Panasonic Lumix DMC-FZ38.
Next time you are out on your travels in the country, or even in the park, garden or city, take a closer look at the trees, shrubs, rocks, walls and paving, and you will see it is alive with a matt or a spot of lichen, which comes in many different forms and colours. So what is lichen? Well, it is usually two organisms living in perfect harmony. One is a mycobiont, the fungal partner of the relationship, and the other is a photobiont, the photosynthetic partner which contains chlorophyll, which can be a green alga or a cyanobactarium.
The names we give lichens is with reference to the fungal partner as every lichen has a unique fungus. The combination of this unique symbiont arrangement between fungus and algae and/or cyanobacteria form the distinct body of the lichen called the thallus. Yet some lichenologists believe that the fungus is actually a parasite, and biologically changes and use the alga or cyanobacterium to obtain nutrients it cannot source elsewhere to sustain itself. Either way, this relationship, symbiont or parasitic, has enabled both parties to survive in many diverse habitats, the fungi gaining essential carbohydrates from the alga or cyanobacterium, and in return the alga or cyanobacterium is protected by the fungus by helping to keep it moist and from solar damage. To complicate matters, and what can be somewhat of an enigma, the same fungal element maybe present within the alga or cyanobaterium, and may take on completely different forms of lichen which are called photomorphs. Also, some lichens have both algae and cyanobacteria, and also may change these around using other photobionts during the different stages of the lichen’s life cycle.
The lichen body is normally made up of mostly fungi, the photobiont is usually only about 20% or less. The different forms of lichen range from foliose, which are leafy forms, crustose, which are powdery or crust-like structures, fruiticose, are like tiny shrubs or tufted vegetation, and squamulose, which are like scales or plates. Within the body the lichen produces fruting bodies which aid in reproduction. Like other non-licenised fungi, these structures contain spores which are released into the environment.
Lichens are very resilient organisms, and they live in extreme habitats other species could simply not tolerate or survive in. They can also survive on our industrial waste pollutants, and can be good biometers for the environment. As important elements within the ecosystem, lichens provide a good food source for invertebrates and vertebrates. Yet some lichens don’t survive the chemical attack of toxins we humans release into the environment, finding it difficult or impossible to exist, and even if they do they can carry these toxins with them through the food chain. So next time you are out and about, take a look around and spare a thought for these most beautiful, enigmatic, and important treasures of our world, and consider that these were amongst the very first living things to emerge from the primordial soup and which allowed others to colonise the land.
Please note that lichen identification is not easy through visuals alone, and to definitively identify some of the similar species specifically would need a microscope and chemical testing. I have identified the species gathered here mainly via morphology and the substrate they were found on, and the environmental conditions. On some tricky species I have spent many hours studying various reference material to ensure the most accurate identification, but please be aware that errors still may creep in, and if so please let me know via my contact page.
Also called ‘Yellow Scales’, this is a bright striking foliose lichen, which is golden-yellow to orange, and is green where shaded from the sun. The disc like structures are more orange with a pale margin. Thallus up to 8cm across.
Found mainly growing on sun exposed bark, but also rocks and walls, roofs, paving, and other man-made structures where nutrient enrichment via bird droppings is found. It is particularly common in coastal areas where the multitudes of seabirds provides the nutrients which it requires. Common and widespread throughout the British Isles.
This organism is made up of a single-celled green algae which feeds the fungi in return for moisture retention in times of drought, and also for acting as a sun block from UV radiation with its yellow pigmentation. Xanthoria parietina is particularly resilient to pollutants such as nitrogen and ammonia, and actively thrives on them, which makes it an excellent biomonitor for measuring levels of toxic elements in any given environment.
Photograph of Golden Shield Lichen (Xanthoria parietina), taken February 2012, growing on willow and oak, Staffordshire. © Pete Hillman 2012. Camera used Panasonic Lumix DMC-FZ38.
This lichen has a blue-grey foliose thallus with flat creeping lobes, and distinct dark grey to brown or black discs in the centre.
Found on trees and shrubs in open areas. Widespread and locally common.
Photograph of Physcia aipolia, taken March 2012, local canal, Staffordshire. © Pete Hillman 2012. Camera used Panasonic Lumix DMC-FZ38.
This is a bushy fruticose, pendulous grey-green to yellow-green lichen, with a blackened base and annular rings or cracks. The branches are cylindrical and tapered. The side branches are not tapered where they meet the trunk as they are in some species. The trunk and branches are covered in patches of soredia or isidia, whilst apothicia are rare.
Rarely found on rocks, but found the on the trunks and in particular the branches of trees where light is able to filter through. Very pollutant resistant. A common and widespread species.
Photograph of Usnea subfloridana, taken December 2012, local canal, Staffordshire. © Pete Hillman 2012. Camera used Nikon Coolpix P500.
It’s like looking into an alien world, but it our world, and the world of lichen. This trumpet lichen grows on the bough of an old willow by my local river, and it is a bit like looking in on an alien landscape. This is a tiny grey-green cup-shaped lichen. Closer inspection reveals a rough, granulated appearance. This lichen is composed of a fungus and an algae which form a symbiotic relationship, where both life forms benefit each other. The trumpet-shaped podetia (cup-like structure) holds the apothecium (reproductive structure) and helps aid in spreading the lichen’s spores when raindrops splash down inside them. Podetia 6 to 30mm tall, 2 to 6mm diameter cups.
Found on soil and rotting wood. Common and widespread.
Looking closer at the image below the lichen can just about be seen growing amongst the thick mat of moss on this large willow branch.
Photograph of Trumpet Lichen (Cladonia fimbriata) taken February 2012, by local river, Staffordshire. © Pete Hillman 2012. Camera used Panasonic Lumix DMC-FZ38.
This is one of several species of ‘pixie-cup’ lichen. The podetia (cups) have a tendency to take on a brownish colour. The basal squamules (leaf-like structures) can be large, especially in older specimens, which may form a carpet of rosettes commonly tinged with pink. It can grow up to 1.5cm tall, and the cups 1cm in diameter.
Found on soil, rocks and mortar, on base-rich substrates. Locally common and widespread throughout Britain.
Photographs taken February 2014, nature reserve, Staffordshire.
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