Gary K. Smith / Common hawthorn (Crataegus laevigata) blossom on white background.

Sylvain Cordier / Fat dormouse (Myoxus glis) eating fruit of English hawthorn (Crataegus laevigata), Alsace, France

Matthew Maran / Hawthorn tree flowers (Crataegus laevigata) Hampstead Heath, London, England, UK. May.

Matthew Maran / Hawthorn tree leaves (Crataegus laevigata) Hampstead Heath, London, England, UK, March.

Will Watson / Midland hawthorn (Crataegus laevigata) in flower, Tiddesley Wood Nature Reserve, Worcestershire, England, UK, March.

Will Watson / Midland hawthorn (Crataegus laevigata) in flower, Tiddesley Wood Nature Reserve, Worcestershire, UK, March.

Ingo Bartussek / Whitethorn flowers {Crataegus oxyacantha} Germany

Ingo Bartussek / Whitethorn berries {Crataegus oxyacantha} Germany

Robert Thompson / Hawthorn (Crataegus laevigata) flowers, Brackagh Moss National Nature Reserve, County Armagh, Northern Ireland. May.

Dave Watts / Prickly box (Bursaria spinosa). Tasmania, Australia. December.

Nigel Cattlin / Hawthorn or May blossom (Crataegus monogyna) corymbs of white flowers with fresh green foliage, Berkshire, England, UK, May