Nick Upton / Close-up of a Meadow brown butterfly (Maniola jurtina) nectaring on a Greater knapweed flower (Centaurea scabiosa) in a chalk grassland meadow, Wiltshire, England, UK, June.

Nick Upton / Two Dark green fritillary butterflies (Argynnis aglaja) and a Narrow-bordered five-spot burnet moth (Zygaena lonicerae) nectaring on a Greater knapweed flower (Centaurea scabiosa) in a chalk grassland...

Nick Upton / Six-spot burnet moth (Zygaena filipendulae), Marbled white butterflies (Melanargia galathea) and a Dark green fritillary (Argynnis aglaja) nectaring on a clump of Greater knapweed flowers (Centaurea s...

Nick Upton / Marbled white butterflies (Melanargia galathea) nectaring on a clump of Greater knapweed flowers (Centaurea scabiosa) in a chalk grassland meadow, Wiltshire, England, UK, June.

Nick Upton / Marbled white butterflies (Melanargia galathea) nectaring on a clump of Greater knapweed flowers (Centaurea scabiosa) in a chalk grassland meadow, Wiltshire, England, UK, June.

Nick Upton / Close-up of a Dark green fritillary (Argynnis aglaja) nectaring on a Greater knapweed (Centaurea scabiosa) flower and flying off, Wiltshire, England, UK, July.

Sven Zacek / Cornflower (Centaurea cyanus) at sunset, with bokeh affect, Jogevamaa, Estonia, June.

Ann & Steve Toon / Cornfield annual summer wildflowers growing on one of the plant charity Landlife's National Wildflower Farms, St Helens, Merseyside, UK, June.

Ann & Steve Toon / Wildflowers, including poppies (Papaver rhoeas), corn marigold (Glebionis segetum), cornflowers (Centaurea cyanus) and corn chamomile (Anthemis arvensis), being grown for seed by Landlife, Fir Tree Fa...

Paul Harcourt Davies / Floral colour in fields on the Piano Grande from Poppies (Papaver rhoeas), Cornflowers (Centaurea), Mustard (Brassica) and Mayweed (Anthemis), Umbria, Italy, June

Paul Harcourt Davies,Paul Harcourt Davies / Cornflowers (Centaurea cyanus) and Mayweed (Anthemis) on the Piano Grande, Umbria, Italy, June 2010

Paul Harcourt Davies,Paul Harcourt Davies / Cornflowers (Centaurea cyanus) in fallow fields, near Sugano, Orvieto, Italy, June