Alan Watson / Heart-shaped patch of lungwort (Lobaria virens) on the moss-covered trunk of Oak tree (Quercus petraea) and Holly trees (Ilex aquifolium) temperate forest, Tomies Wood, Killarney National Park, County...

Alan Watson / Heart-shaped patch of lungwort (Lobaria virens) on the moss-covered trunk of Oak tree (Quercus petraea) and Holly trees (Ilex aquifolium) temperate forest, Tomies Wood, Killarney National Park, County...

Adrian Davies / Tree lungwort (Lobariella pseudocrenulata) amongst moss on tree trunk. Savegre Valley, Costa Rica.

Adrian Davies / Tree lungwort (Lobariella pseudocrenulata) with apothecia fruiting bodies. Savegre Valley, Costa Rica.

Niall Benvie / Tree lungwort (Lobaria pulmonaria) Crinan Wood, Crinan, Argyll, Scotland, UK, July.

Staffan Widstrand / Wild Wonders of China / Tree lungwort (Lobaria pulmonaria) growing on tree in humid montane mixed forest, Laba He National Nature Reserve, Sichuan, China

Nick Upton / Tree lungwort / Lung lichen (Lobaria pulmonaria) growing on a treetrunk in ancient Atlantic woodland, Knapdale Forest, Argyll, Scotland, UK, May.

Chris Mattison / Foliose lichen (Lobaria scrobiculata) on birch bark. Sensitive to pollution. Drumnadrochit, Inverness, Scotland

Cyril Ruoso / Tree lungwort (Lobaria pulmonaria) lichen in ancient forest,, Alberes Mountains. Massane reserve, Pyrenees, France, November.

Nick Upton / Tree lungwort / Lung lichen (Lobaria pulmonaria) patch growing on a tree trunk in montane Laurel forest, Anaga Mountains, Tenerife, May.

Alex Hyde / Tree Lungwort (Lobaria pulmonaria) lichen close up, Kyle of Lochalsh, Scotland. March.

Alex Hyde / Tree lungwort (Lobaria pulmonaria) lichen growing on a mature beech tree. Kyle of Lochalsh, Scotland. March.

Alex Hyde / Tree lungwort (Lobaria pulmonaria) lichen growing on a mature beech tree. Kyle of Lochalsh, Scotland. March.

Alex Hyde / Tree lungwort (Lobaria pulmonaria) lichen. Kyle of Lochalsh, Scotland. March.

Alex Hyde / Tree lungwort (Lobaria pulmonaria) lichen growing on a mature beech tree. Kyle of Lochalsh, Scotland. March.

Alex Hyde / Tree lungwort (Lobaria pulmonaria) lichen growing on a mature beech tree. Kyle of Lochalsh, Scotland. March.

Robert Thompson / Tree lungwort (Lobaria pulmonaria) Tomies Wood, Killarney National Park, County Kerry, Ireland, November

Alex Hyde / Tree lungwort lichen (Lobaria pulmonaria) Inverness-shire. Scotland, UK.

Adrian Davies / Tree Lungwort (Lobaria pulmonaria) growing on oak bark. Red parts are spore releasing bodies. The Trossachs, Scotland, February.

Adrian Davies / Tree Lungwort (Lobaria pulmonaria) growing on oak bark. Red parts are spore releasing bodies. The Trossachs, Scotland, February.

Adrian Davies / Tree Lungwort (Lobaria pulmonaria) growing on oak bark. Red parts are spore releasing bodies. The Trossachs, Scotland, February.

Adrian Davies / Tree Lungwort (Lobaria pulmonaria) growing on oak bark. The Trossachs, Scotland, February.

Adrian Davies / Tree Lungwort (Lobaria pulmonaria) growing on oak bark. The Trossachs, Scotland, February.

Adrian Davies / Dog Lichen (Peltigera sp) and Tree Lungwort (Lobaria pulmonaria) growing on oak bark. The Trossachs, Scotland, February.

Adrian Davies / Dog Lichen (Peltigera sp) and Tree Lungwort (Lobaria pulmonaria) growing on oak bark. The Trossachs, Scotland, February.

Alan Watson / Insect amongst apothecia of Lungwort (Lobaria virens), on Oak tree (Quercus petraea) temperate forest, Tomies Wood, Killarney National Park, County Kerry, Republic of Ireland, Europe

Alan Watson / Toadstool growing amongst apothecia of Lungwort (Lobaria virens), on Oak tree (Quercus petraea) temperate orest, Tomies Wood, Killarney National Park, County Kerry, Republic of Ireland, Europe

Alan Watson / Lungwort (Lobaria virens) with apothecia visible, on an Oak tree (Quercus petraea), temperate forest, Tomies Wood, Killarney National Park, County Kerry, Republic of Ireland, Europe

Alan Watson / Lungwort (Lobaria virens) on Oak tree (Quercus petraea) temperate forest, Tomies Wood, Killarney National Park, County Kerry, Republic of Ireland, Europe

Alan Watson / Lungwort (Lobaria virens) on Oak tree (Quercus petraea) temperate forest, Tomies Wood, Killarney National Park, County Kerry, Republic of Ireland, Europe

Alan Watson / Pored lungwort (Lobaria scrobiculata) growing amongst moss on Oak tree (Quercus petraea) temperate forest, Tomies Wood, Killarney National Park, County Kerry, Republic of Ireland, Europe

Alan Watson / Lungwort (Lobaria virens) on a yew tree (Taxus baccata) in temperate forest, Killarney National Park, County Kerry, Republic of Ireland, Europe

Alan Watson / Tree lungwort (Lobaria pulmonaria) growing on a log in inland temperate rainforest, Goat Range Provincial Park, British Columbia, Canada.

Robert Thompson / Tree lungwort (Lobaria pulmonaria) and moss on bark, Glen Wood, County Fermanagh, Northern Ireland, UK, February

Robert Thompson / Tree lungwort {Lobaria pulmonaria} Florencecourt, County Fermanagh, Northern Ireland, UK, February

Ross Hoddinott / Tree lungwort {Lobaria pulmonaria} Lanhydrock woodland, Cornwall, UK. October

Jerry Monkman / Lichens, Tree lungwort {Lobaria pulmonaria} (green) and {Anzia colpodes} on a maple tree, Acadia National Park, Maine, USA

Duncan Mcewan / Lichen {Lobaria laetivirens} with apothecia on tree bark Scotland, UK Inverness-shire

Duncan Mcewan / Tree lungwort {Lobaria pulmonaria}, on Hazel, Inverness-shire

Niall Benvie / Tree lungwort on Hazel. (Lobaria pulmonaria) Scotland. Epiphytic lichen.

Niall Benvie / Tree Lungwort {Lobaria pulmonaria} on bare wood Scotland UK

Niall Benvie / Tree lungwort {Lobaria pulmonaria} fallen from oak into leaf litter. Scotland, UK Glen

Duncan Mcewan / Pored lungwort lichen {Lobaria scrobiculata} on tree bark Scotland UK Inverness-shire

Robin Chittenden / Green lungwort (Lobaria pulmonaria) Craig, Plocton, Highland, Scotland, England, December