Nick Upton / Garden chair well covered with extensive growths of lichen, including filamentous forms (Usnea sp.), (Evernia prunastri) and Foliose (Flavoparmelia caperata), Cornwall, UK, August.

Nigel Cattlin / Traveller's joy (Clematis vitalba) flowering in hedgerow, Berkshire, England, UK. August.

Bruno D'Amicis / Detail of centuries-old Beech tree (Fagus sylvatica) covered in lichens and mosses. Val Cervara old-growth beech forest. Europe's oldest beech forest. Abruzzo, Lazio and Molise National Park / Par...

Staffan Widstrand / Wild Wonders of China / Temperate cloud forest with Usnea lichens hanging from trees, near the glacier lake at Mount Bawu Bameng, Meili Snow Mountain National park, Yunnan, China. October 2017.

Staffan Widstrand / Wild Wonders of China / Lichen covered (Usnea longissima) and lichen hanging from the trees in temperate cloud forest, in the Meili Snow Mountain National park, Yunnan China. October

Staffan Widstrand / Wild Wonders of China / Lichen (Usnea Longissima) covered trees in temperate cloud forest, in the Meili Snow Mountain National park, Yunnan China. October

Staffan Widstrand / Wild Wonders of China / Lichen covered (Usnea Longissima) and lichen hanging from the trees in temperate cloud forest, in the Meili Snow Mountain National park, Yunnan China. October

Staffan Widstrand / Wild Wonders of China / Lichen (Usnea Longissima) covered trees in temperate cloud forest, in the Meili Snow Mountain National park, Yunnan China. October 2017.

Staffan Widstrand / Wild Wonders of China / Temperate cloud forest with Lichen (Usnea longissima) near the glacier lake at Mount Bawu Bameng, in the Meili Snow Mountain National park, Yunnan China. October 2017.

Staffan Widstrand / Wild Wonders of China / Temperate cloud forest with lichen (Usnea longissima) hanging from tree, near the glacier lake at Mount Bawu Bameng, in the Meili Snow Mountain National park, Yunnan, China. October.

Staffan Widstrand / Wild Wonders of China / Wild Wonders of China. team holding up their flag in the lichen-covered (Usnea longissima) temperate cloud forest, in the Meili Snow Mountain National park, Yunnan China. October

Staffan Widstrand / Wild Wonders of China / Lichen (Usnea longissima) and other plants on tree trunk in cloud forest , near the glacier lake at Mount Bawu Bameng, Meili Snow Mountain National park, Yunnan China. October.

Staffan Widstrand / Wild Wonders of China / Lichen (Usnea longissima) hanging from a tree. Temperate cloud forest sceneries, near the glacier lake at Mount Bawu Bameng, in the Meili Snow Mountain National park, Yunnan, China. October 2017.

Ashley Cooper / Sadhu or Hindu holy man in Kathmandu, Nepal. Sadhus are men who have renounced all material attachments to concentrate on their spirituality. January 2013.

Felis Images / Sikkim spruce (Picea spinulosa) branches with male (purple) and female (orange) cones covered in Usnea lichen. Lava, Bhutan.

Felis Images / Sikkim spruce (Picea spinulosa) branches with male (purple) and female (orange) cones covered in Usnea lichen. Lava, Bhutan.

Ernie Janes / Oldmans beard (Clematis vitalba) seedheads silhouetted at sunset, Norfolk, England, UK. January.

Colin Varndell / Traveller's joy (Clematis vitalba) flower. Portland, Dorset, England, UK. July.

Colin Varndell / Traveller's joy (Clematis vitalba) Dorset, UK, October.

Adrian Davies / Lichen (Usnea florida) Snowdonia, North Wales, October.

Adrian Davies / Lichen (Usnea florida) Snowdonia, North Wales, October.

Adrian Davies / Lichen (Usnea florida) Snowdonia, North Wales, October.

Ingo Arndt / Primary or old growth rainforest with dead tree covered with Beard lichen (Usnea) Arfak Mountains, West Papua, Indonesia.

Fabrice Cahez / Traveller's joy (Clematis vitalba), Vosges, France, September.

Nick Upton / Old man's beard, the seedheads of Wild clematis (Clematis vitalba) in a hedgerow, Wiltshire, UK, September.

Solvin Zankl / Lichen (Usnea dasypoga) on English oak tree (Quercus robur) near Norra Kvill National Park, Rumskulla socken, Smaland, Sweden, August.

Solvin Zankl / Lichens (Usnea filipendula, Evernia prunasti, Bryoria fuscescens, Hypogymnia physodes and Parmelia sulcata) on English oak tree (Quercus robur) near Norra Kvill National Park, Smaland, Sweden, August.

Solvin Zankl / Lichen (Usnea dasypoga) on English oak tree (Quercus robur) near Norra Kvill National Park in Rumskulla socken, Smaland, Sweden

Eric Baccega / Head portrait of old Afar man, with beard dyed with henna, Ahmed Ela village, Danakil depression, Afar region. Ethiopia, March 2015.

Eric Baccega / Head portrait of old Afar man, with beard dyed with henna, Ahmed Ela village, Danakil depression, Afar region. Ethiopia, March 2015.

Eric Baccega / Head portrait of old Afar man, with beard dyed with henna, Ahmed Ela village, Danakil depression, Afar region. Ethiopia, March 2015.

Nick Upton / Traveller's joy / Old man's beard (Clematis vitalba) flowers, Wiltshire, UK, July.

Dong Lei / Forest with trees covered in Old man's beard (Usnea) and Rhododendron flowers (Rhododendron sp) Lijiang Laojunshan National Park, Yunnan Province, China. April.

Fabrice Cahez / Frost on Old Man's Beard seedheads (Clematis vitalba) in winter, Vosges, France

Axel Gebauer / Coal tit (Parus ater) on branch with Old man's beard lichen (Usnea) Djuga, Kavkazsky Zapovednik, west Caucasus Mountains, Adygea, Russia, March.

David Tipling / Siberian Tit (Parus cinctus) on Old man's beard lichen, Finland, March.

Loic Poidevin / Old man's beard lichen (Usnea longissima), Khutzeymateen Grizzly Bear Sanctuary, British Columbia, Canada, June.

Dr. Axel Gebauer / Beard lichen (Usnea), Gonggai Shan Nature Reserve, Kangding / Dartsedo, Tibet, China, August.

XI ZHINONG / Old Man's beard lichen (Usnea longissima) food of Yunnan snub-nosed monkey (Rhinopithecus bieti), Baimaxueshan Nature reserve, Yunnan, China, November

Nick Upton / Garden chair well covered with extensive growths of lichens including Oakmoss (Evernia prunastri) filmanetous forms (Usnea esperantiana and other Usnea spp) and a foliose lichen (Flavoparmelia caperat...

Ernie Janes / Old mans Beard (Clematis vitalba) seedheads at sunset, Norfolk, November

Alex Hyde / Old man's beard Lichen (Usnea sp) growing on tree trunk in coniferous woodland in Aosta Valley, Monte Rosa Massif, Pennine Alps, Italy. July.

Alex Hyde / Bearded Lichen (Usnea sp.) growing on a Scots Pine (Pinus sylvestris). Fasnakyle Forest, Glen Affric, Caledonian Forest Reserve, Scotland, November.

Rolf Nussbaumer / Blue mud dauber wasp (Chalybion californicum) adult in flight among Old man's beard (Clematis drummondii) flowers, Dinero, Lake Corpus Christi, South Texas, USA.

Nature Production / Beard Moss (Usnea longissima) covering trees, Mt. Nyukasa, Nagano, Japan, September

Nick Upton / Old man's beard, the seedheads of Wild Clematis (Clematis vitalba) in an autumn hedgerow. Wiltshire, UK, October.

Nick Upton / Old man's beard, the seedheads of Wild Clematis (Clematis vitalba) against blue sky. Wiltshire, UK, October.

Nick Upton / Old man's beard, the seedheads of Wild Clematis (Clematis vitalba) close up view against blue sky. Wiltshire, UK, October.

Nick Upton / Old man's beard, the seedheads of Wild Clematis (Clematis vitalba) in an autumn hedgerow. Wiltshire, UK, October.

Nick Upton / Old man's beard, the seedheads of Wild Clematis (Clematis vitalba) in an autumn hedgerow. Wiltshire, UK, October.

Florian Möllers / Old Man's beard clematis (Clematis vitalba) flowers, Berlin, Germany, September

Adrian Davies / Traveller's Joy / Old Man's Beard (Clematis vitalba) growing in hedgerow, UK, August

Adrian Davies / Beard Lichen (Usnea subfloridana) a good indicator of clean air, UK

Robert Thompson / Old man's beard lichen {Usnea cornuta} Killary Bay Little, County Mayo, Republic of Ireland, February

Robert Thompson / Old man's beard lichen {Usnea cornuta} Crom Estate, County Fermanagh, Northern Ireland, UK, March

Angelo Gandolfi / Chamois (Rupicapra rupicapra) feeding on Old Man's Beard lichens (Usnea sp) during a harsh winter, Abruzzo National Park, Italy.

Angelo Gandolfi / Chamois (Rupicapra rupicapra), watched by another, feeding on Old Man's Beard lichens (Usnea sp) during a harsh winter, Gran Paradiso NP, Alps, Italy.

Wild Wonders of Europe / Benvie / Traveller's joy / Old man's beard (Clematis vitalba) in flower with fly on one of the petals, Fliess, Naturpark Kaunergrat, Tirol, Austria, July 2008

Kim Taylor / Wild clematis / Old man's beard (Clematis vitalba) seed heads, Surrey, England

Stephen Belcher / Silver Beech (Nothofagus menziesii) with Old Man's Beard (Clematis vitalba) growing on the branches, Fiordland National Park, New Zealand

Wild Wonders of Europe / Widstrand / Lichen {Usnea filipendula} on a Spruce (Picea abies) Oulanka, Finland, September 2008

Wild Wonders of Europe / Widstrand / Lichen {Usnea filipendula} on a Spruce (Picea abies) Oulanka, Finland, September 2008

Wild Wonders of Europe / Widstrand / Lichen {Usnea filipendula} on a Spruce (Picea abies) Oulanka, Finland, September 2008

Wild Wonders of Europe / Widstrand / Lichen {Usnea filipendula} on a Spruce (Picea abies) Oulanka, Finland, September 2008

Ross Hoddinott / Lichen {Usnea ceratina} and {Parmelia sulcata} Devon, UK. October

Gary K. Smith / Old man's beard / Travellers joy {Clematis vitalba} growing in hedgerow showing seed-head plumes and flowers, Norfolk, UK, September

Gary K. Smith / Old man's beard / Travellers joy {Clematis vitalba} growing in hedgerow showing seed-head plumes and flowers, Norfolk, UK, September

Flip de Nooyer / Old man's beard lichen {Usnea sp} growing on pine tree, Netherlands

Duncan Mcewan / Lichen {Usnea sp} and {Parmelia sp} on birch bark {Betula sp} Scotland, UK Inverness-shire

Duncan Mcewan / Lichen {Usnea sp} on bark of Birch tree {Betula sp} Scotland, UK Inverness-shire

Duncan Mcewan / Lichen {Usnea sp} on bark of Birch tree {Betula sp} Scotland, UK Inverness-shire

RHONDA KLEVANSKY / Alastair MacEwen filming Old man's beard on trees Nahuelbuta, for BBC series Andes to Amazon

Adrian Davies / Old man's beard (Traveller's joy) seeds {Clematis vitalba} Southern England, UK

Gertrud & Helmut Denzau / Saddhu, religious wise man, with long beard and facial paint markings, India

Philippe Clement / Old Man's Beard {Usnea longissima} hanging from the branches of Western red cedar {Thuja plicata}, Glacier NP, Montana, USA

Niall Benvie / Old man's beard lichen on tree trunk {Usnea sp} Highlands, Scotland, UK

Pascal Tordeux / Old Man's Beard, (Clematis vitalba) in flower. Picardy, France, July.

John Waters / Traveller's Joy / Old Man's Beard {Clematis vitalba} in flower, Dorset, UK

Jim Brandenburg / Elderly man laughing, Harbin, China

David Tipling / Downy birch trees (Betula pubescens) festooned with Old Mans beard lichens (Usnea sp.), Glen Affric, Scottish Highlands, UK. May.

David Tipling / Downy birch trees (Betula pubescens) festooned with Old Mans beard lichens (Usnea sp.), Glen Affric, Scottish Highlands, UK. May.

Paul Harcourt Davies / Old man's beard (Clematis vitalba) leaf changing colour in Autumn, Podere Montecucco, Orvieto, Umbria, Italy. October.

Will Watson / Grey sallow (Salix cinerea) branches covered by Beard lichen (Usnea sp.), Lochan, Darnaway Estate, Highlands, Scotland, UK. May.

Robert Thompson / Beard lichen (Usnea cornuta) growing on a tree branch, Ards Forest Park, County Donegal, Republic of Ireland. October.

Paul Harcourt Davies / Old man's beard (Clematis vitalba) seed head, Umbria, Italy. September.

Nick Upton / Old man's beard, the seedheads of Wild clematis (Clematis vitalba) in a hedgerow, Wiltshire, UK, September.

Nick Upton / Old man's beard, the seedheads of Wild clematis (Clematis vitalba) and Hawthorn (Crataegus monogyna) berries in a hedgerow, Wiltshire, UK, September.

Dave Watts / Southern clematis (Clematis aristata). Tasmania, Australia. November.

Niall Benvie / Wild clematis (Clematis vitalba) Larochemillay, France, September.

Niall Benvie / Wild clematis (Clematis vitalba) against white background, Burgundy, France, July.

Linda Pitkin / Traveller's-joy (Clematis vitalba) on bank of River Thames. Hampton Court, Richmond Upon Thames, England, UK. July.

Linda Pitkin / Traveller's-joy (Clematis vitalba), flowers and seed heads, Desborough Island, Surrey, England.

Ernie Janes / Old man's beard flowers (Clematis vitalba) Thornham Dunes, Norfolk, England, UK, August. August