Fergus Gill / 2020VISION / Chequered skipper (Carterocephalus palaemon) nectaring on a thistle (Cirsium), Glasdrum Wood National Nature Reserve, near Oban, Argyll, Scotland, UK, June.

Terry Whittaker / 2020VISION / Marsh Thistle (Cirsium palustre) flowering on managed grazing land, Wicken Fen, Cambridgeshire, UK, June

Ernie Janes / Silhouette against the sun of floating seeds attached to Scottish spear thistle (Cirsium vulgare), UK. August

B&S Draker / Three Black-chinned Hummingbird (Archilochus alexandri) females feeding on Texas thistle (Cirsium texanum). Sinton, Corpus Christi, Coastal Bend, Texas, USA, May.

Wild Wonders of Europe / Hermans / Melancholy thistle (Cirsium heterophyllum) flowers, Cliffs of Moher, County Clare, Republic of Ireland, June 2009

Ross Hoddinott / Marsh fritillary {Euphydryas aurinia} butterfly resting on Meadow thistle flower {Cirsium helenoides} Dunsdon, Devon, UK. June

Wild Wonders of Europe / Wothe / Flowering meadow with Thistles (Cirsium rivulare) and Buttercups (Ranunculus acris) Poloniny National Park, Western Carpathians, Eastern Slovakia, Europe, June 2009

Wild Wonders of Europe / Wothe / Flowering meadow with Thistles (Cirsium rivulare) Poloniny National Park, Western Carpathians, Eastern Slovakia, Europe, June 2009

Wild Wonders of Europe / Wothe / Flowering meadow with Thistles (Cirsium rivulare) and Buttercups (Ranunculus acris) Poloniny National Park, Western Carpathians, Eastern Slovakia, Europe, June 2009

Wild Wonders of Europe / Wothe / Goldfinch (Carduelis carduelis) on flowering thistle (Cirsium rivulare) Poloniny National Park, East Slowakia, Europe, June 2008

Kim Taylor / Black-tipped Soldier Beetle {Rhagonycha fulva} taking off from Creeping Thistle {Cirsium arvense} Surrey, England.

Nick Upton / Stemless thistle (Cirsium acaule) flowering on south facing slope of a chalk grassland meadow, Wiltshire, UK, August.

Nick Upton / Stemless thistle (Cirsium acaule) flowering on south facing slope of a chalk grassland meadow, Wiltshire, UK, August.

Nick Upton / A Marsh fly / Snail-killing fly (Dichetophora finlandica), nationally scarce in the UK, standing on a Woolly thistle leaf (Cirsium eriophorum), chalk grassland meadow, Wiltshire, UK, June.

Nick Upton / Sunfly (Helophilus pendulus) feeding on Woolly thistle flower (Cirsium eriophorum), chalk grassland meadow, Wiltshire, UK, August.

Fergus Gill / 2020VISION / Chequered skipper (Carterocephalus palaemon) nectaring on a thistle (Cirsium), Glasdrum Wood National Nature Reserve, near Oban, Argyll, Scotland, UK, June.

Fergus Gill / 2020VISION / Chequered skipper (Carterocephalus palaemon) nectaring on a thistle (Cirsium), Glasdrum Wood National Nature Reserve, near Oban, Argyll, Scotland, UK, June.

Wild Wonders of Europe / Widstrand / Tuberous thistle (Cirsium tuberosum) North Velebit National Park, Velebit Nature Park, Rewilding Europe area, Velebit mountains, Croatia

Fabrice Cahez / Woolly Thistle (Cirsium eriophorum) Lozere, France, July.

Alex Hyde / Mountain Clouded Yellow Butterfly (Colias phicomone) on Tuberous Thistle (Cirsium tuberosum), against white background. Nordtirol, Tirol, Austian Alps, Austria, August.

MYN / Marko Masterl / Woolly thistle (Cirsium eriophorum) in flower, Kocevje, Slovenia, meetyourneighbours.net project

MYN / Marko Masterl / Marbled white butterfly (Melanargia galathea) and camouflaged Southern green stink bug (Nezara viridula) on thistle flower (Cirsium), Kovevje, Slovenia, August, meetyourneighbours.net project

MYN / Marko Masterl / Spear thistle (Cirsium vulgare) in flower, Kocevje, Slovenia, August, meetyourneighbours.net project

MYN / Brady Beck / Sandhill thistle (Cirsium repandum) Scotland County, North Carolina, USA, May, meetyourneighboursproject.net

Nick Upton / Dark green fritillary butterfly (Argynnis aglaja) resting on Pannonic thistle leaf (Cirsium pannonicum), Julian Alps, Slovenia, July

Nick Upton / Pannonic thistle (Cirsium pannonica) clump flowering in a traditional hay meadow at 1200m, Julian Alps, Slovenia, July

MYN / Niall Benvie / Melancholy thistle (Cirsium helenioides / Cirsium heterophyllum) in flower, Scotland, UK, June

Laurie Campbell / Spear thistle (Cirsium vulgare) flowering, Isle of Skye, Scotland, July

Nick Upton / Parasite fly / Tachinid fly (Prosena siberita) with distinctive long proboscis, resting on Woolly thistle leaf (Cirsium eriophorum), chalk grassland meadow, Wiltshire, UK, July.

Nick Upton / Female Meadow grasshopper (Chorthippus parallelus) resting on Woolly thistle leaf (Cirsium eriophorum), chalk grassland meadow, Wiltshire, UK, July.

Nick Upton / Marsh fly / Snail-killing fly (Limnia unguicornis) on Woolly thistle leaf (Cirsium eriophorum), chalk grassland meadow, Wiltshire, UK, July.

Alex Hyde / Woolly thistle (Cirsium eriophorum) in alpine meadow, Nordtirol, Austrian Alps, Austria, August.

Nick Upton / Woolly Thistle (Cirsium eriophorum) flowers hanging down over chalk grassland meadow. Wiltshire, UK, August.

Nick Upton / Woolly Thistle (Cirsium eriophorum) flowerhead. Wiltshire, UK, August.

Nick Upton / Woolly Thistle (Cirsium eriophorum) plant with large spiky flowerbud. Wiltshire, UK, July.

Colin Varndell / Seed head of Woolly thistle (Cirsium eriophorum) flower, Dorset, UK, September

MYN / Marko Masterl / Yellow thistle (Cirsium genus) close up of flowering heads, Slovenia, Europe, July. meetyourneighbours.net project

LYNN M. STONE / Great spangled fritillary butterfly (Speyeria cybele) and Bumble bees (Bombus) feeding on Bull / Spear thistle (Cirsium vulgare) flower, Durham, Connecticut, USA, August

Ernie Janes / Melancholy thistles (Cirsium helenioides) flowering, Norfolk, UK, May

Guy Edwardes / 2020VISION / Woolly / Spear thistle (Cirsium vulgare) close-up of flower showing unopened flowerhead, Parsonage Down, Wiltshire, UK, June

Guy Edwardes / 2020VISION / Woolly / Spear thistle (Cirsium vulgare) close-up of flower showing unopened flowerhead, Parsonage Down, Wiltshire, UK, June

Guy Edwardes / 2020VISION / Woolly / Spear thistle (Cirsium vulgare) close-up of flower showing unopened flowerhead, Parsonage Down, Wiltshire, UK, June

Guy Edwardes / 2020VISION / Woolly / Spear thistle (Cirsium vulgare) close-up of flower showing unopened flowerhead, Parsonage Down, Wiltshire, UK, June

Terry Whittaker / 2020VISION / Marsh Thistle (Cirsium palustre) flowering on managed grazing land, Wicken Fen, Cambridgeshire, UK, June

Terry Whittaker / 2020VISION / Marsh Thistle (Cirsium palustre) flowering on managed grazing land, Wicken Fen, Cambridgeshire, UK, June

Terry Whittaker / 2020VISION / Marsh Thistle (Cirsium palustre) flowering on managed grazing land, Wicken Fen, Cambridgeshire, UK, June

Ernie Janes / Silhouette against the sun of floating seeds attached to Scottish spear thistle (Cirsium vulgare), UK. August

Ernie Janes / Melancholy Thistle (Cirsium helenioides) and Buttercups (Ranunculus sp) flowering in meadow, UK

Andy Sands / Melancholy thistles (Cirsium helenioides) growing on roadside verge, Upper Teesdale, Co. Durham, England, UK, June 2009

Andy Sands / Melancholy thistle (Cirsium helenioides) close up of flower, Upper Teesdale, Co. Durham, England, UK, June

Rolf Nussbaumer / Pipevine Swallowtail butterfly (Battus philenor) feeding on flowering Texas thistle (Cirsium texanum) Fennessey Ranch, Refugio, Coastal Bend, Texas Coast, USA

Rolf Nussbaumer / Blue-throated Hummingbird (Lampornis clemenciae)feeding on flowering Texas thistle (Cirsium texanum) Chisos Basin, Chisos Mountains, Big Bend National Park, Chihuahuan Desert, West Texas, USA

Stephen Dalton / Spear thistle (Cirsium vulgare) flower, UK

Russell Cooper / Flower of the Spear Thistle (Cirsium vulgare) UK.

Russell Cooper / Common Carder bumblebee (Bombus pascuorum) feeding on nectar from a Spear Thistle (Cirsium vulgare) UK.

Wild Wonders of Europe / Wothe / Flowering meadow with Thistles (Cirsium rivulare) and Buttercups (Ranunculus acris) Poloniny National Park, Western Carpathians, Eastern Slovakia, Europe, June 2009

Wild Wonders of Europe / Wothe / Flowering meadow with Thistles (Cirsium rivulare) and Buttercups (Ranunculus acris) Poloniny National Park, Western Carpathians, Slovakia, Europe, May 2009

Wild Wonders of Europe / Wothe / Flowering meadow with Thistles (Cirsium rivulare) Poloniny National Park, Western Carpathians, Eastern Slovakia, Europe, June 2009

Wild Wonders of Europe / Wothe / Thistles (Cirsium rivulare) flowering in a meadow, Poloniny National Park, East Slovakia, Europe, June 2008

Nick Garbutt / Melancholy thistle (Cirsium heterophyllum) Isle of Mull, Scotland, UK.

Michael & Patricia Fogden / Magnificent Hummingbird (Eugenes fulgens) male perched on flower of Giant Thistle (Cirsium subcoriaceum), Cerro de la Muerte, Costa Rica

Jose B. Ruiz / Spiniest thistle {Cirsium spinosissimum} flowering in the pyrenees, Huesca, Spain

Bjorn Forsberg / Creeping thistle {Cirsium arvense}, blackfly and other flying insects, Sweden

Gary K. Smith / Melancholy Thistles {Cirsium helenioides} growing in damp meadowland, Norfolk, UK, June

PREMAPHOTOS / Thistle ermine moth (Ethmia terminella) on woolly thistle (Cirsium eriophorum) UK

Thomas Lazar / American Goldfinch (Carduelis tristis) collecting thistle down from Canada Thistle (Cirsium arvense) for nests, USA

Thomas Lazar / American Goldfinch (Carduelis tristis) collecting thistle down from Canada Thistle (Cirsium arvense) for nests, USA

Nature Production / Old World Yellow Swallowtail butterfly {Papilio machaon hippocrates} male sucking nectar from Thistle {Cirsium oligophyllum} Saitama, Japan

Geoff Simpson / Melancholy thistle (Cirsium helenioides) UK

Bjorn Forsberg / Brimstone butterfly {Gonepteryx rhamni} on thistle {Cirsium arvense} Sweden

Ross Hoddinott / Meadow thistle (Cirsium dissectum) Devon, UK.

Colin Varndell / Woolly thistle flower {Cirsium eriophorum} UK.

Niall Benvie / Spear thistle {Cirsium vulgare} cflowering, Scotland, UK.

Georgette Douwma / Common Carder-bee {Bombus pascuorum} on Spear Thistle, {Cirsium vulgare} UK.

Philippe Clement / Spear thistle flower {Cirsium vulgare} Belgium

Geoff Simpson / Melancholy thistle in flower {Cirsium helenioides} Derbyshire, UK.

Duncan Mcewan / Portrait of a Melancholy thistle {Cirsium helenioides} UK

Philippe Clement / Spear thistle flower {Cirsium vulgare} Belgium

Ross Hoddinott / Spear thistle flower {Cirsium vulgare} Cornwall, UK

Niall Benvie / Spear thistle {Cirsium vulgare} flower head, Glen Muick, Deeside, Scotland, UK

Russell Cooper / Spear thistle {Cirsium vulgare} flower , UK

Duncan Mcewan / Spear thistle {Cirsium vulgare} flowering, Isle of Mull, Scotland

Geoff Simpson / Spear thistle {Cirsium vulgare} flowering, UK

Duncan Mcewan / Spear thistle flower buds {Cirsium vulgare} Scotland, UK

Pascal Tordeux / Woolly Thistle (Cirsium eriophorum) in flower. Queyras, south east of France.

Pascal Tordeux / Thistle (Cirsium arvense). French Alps, July.

Pascal Tordeux / Woolly Thistle (Cirsium eriophorum) flower with beetles feeding. South east France, June.

Pascal Tordeux / Lanceolate Thistle (Cirsium lanceolatum). French Alps, July.

Jan Vermeer / Common Thistle (Cirsium vulgare) backlit with buds and flower, Europe, introduced into North America where it is considered an invasive weed