Ernie Janes / 'Red Veined' Sorrel (Rumex acetosa) in garden.

Jack Dykinga / Bracken ferns and Sorrel growing on a felled Redwood tree, Redwood National Park, Prairie Creek, California, USA. June 2017.

Jack Dykinga / Bracken ferns and Sorrel growing on a felled Redwood tree, Redwood National Park, Prairie Creek, California, USA. May 2017.

MYN / Dirk Funhoff / Common sorrel (Rumex acetosa), Büchelberg, Pfalz, Germany. May. Meetyourneighbours.net project

MYN / Dirk Funhoff / Common sorrel (Rumex acetosa), Lorsch, Hessen, Germany. June. Meetyourneighbours.net project

MYN / Dirk Funhoff / Common sorrel (Rumex acetosa), Lorsch, Hessen, Germany. June. Meetyourneighbours.net project

Ross Hoddinott / Harvest mouse (Micromys minutus) feeding on Sorrel (Rumex acetosa), Devon, England, UK. May. Captive

Philippe Clement / Common sorrel / garden sorrel (Rumex acetosa) in flower in meadow, Gran Paradiso National Park, Italy, June

Rod Williams / Common Sorrel (Rumex acetosa) Brockley Cemetery, Lewisham, London. May

Matthew Maran / Common sorrel (Rumex acetosa) flowers, Hampstead Heath, London, England, UK. May.

Matthew Maran / Wildflower field with Common sorrel (Rumex acetosa) and Pignut flowers (Conopodium majus) Hampstead Heath, London, England, UK. May 2015.

Nick Upton / Common sorrel (Rumex acetosa) flowering on slumping cliff at Widemouth Bay, Cornwall, UK, May.

Colin Varndell / Common sorrel (Rumex acetosa) Dorset, UK, June.

Nick Upton / Captive-reared Harvest mouse (Micromys minutus) just after release among seedheads of Common sorrel / Sour Dock (Rumex acetosa), a favoured food source, on a heathland reserve, Kilkhampton Common, Cor...

Nick Upton / Captive-reared Harvest mouse (Micromys minutus) just after release among seedheads of Common sorrel / Sour Dock (Rumex acetosa), a favoured food source, on a heathland reserve, Kilkhampton Common, Cor...

Nick Upton / Captive-reared Harvest mouse (Micromys minutus) being released onto a Bramble bush (Rubus plicatus) on a heathland reserve, Kilkhampton Common, Cornwall, UK, June. Model released.

Nick Upton / Captive-reared Harvest mouse (Micromys minutus) just after release among seedheads of Common sorrel / Sour Dock (Rumex acetosa), a favoured food source, on a heathland reserve, Kilkhampton Common, Cor...

Nick Upton / Captive-reared Harvest mouse (Micromys minutus) just after release among seedheads of Common sorrel / Sour Dock (Rumex acetosa), a favoured food source, on a heathland reserve, Kilkhampton Common, Cor...

Alex Hyde / Common Sorrel (Rumex acetosa) ripening fruits. Derbyshire, UK. June.

Philippe Clement / Common / garden sorrel (Rumex acetosa) in flower, Belgium, April.

Ross Hoddinott / Scarce chaser dragonfly (Libellula fulva) covered in dew, roosting on common sorrel (Rumex acetosa), Lower Tamar Lakes, Cornwall, UK. May.

Nick Upton / Common sorrel (Rumex acetosa) flowering, Kenfig National Nature Reserve, Glamorgan, Wales, UK, June.

Colin Varndell / Close-up of common sorrel (Rumex acetosa) in flower, Dorset, UK, June.

Ross Hoddinott / Small pearl-bordered fritillary (Boloria selene) roosting on common sorrel (Rumex acetosa), Marsland mouth, Devon, UK. May .

Ross Hoddinott / Dock bug (Coreus marginatus) on Common sorrel (Rumex acetosa). Lower Tamar Lakes, Cornwall, England, UK. June.

Nick Upton / Common sorrel (Rumex acetosa) flowering in a meadow among masses of Dandelions (Taraxacum sp.), Wiltshire, UK, May.

Ross Hoddinott / Marsh fritillary butterfly (Euphydrayas aurinia) on sorrel (Rumex acetosa), Dunsdon, Devon, UK. June