For a few days every summer the river Oise colors white with river water-crowfoot (Ranunculus fluitans) flowers. This plant's long stems grow almost completely submerged, but the flowers break the surface so insects can pollinate them. Thiérache, France. Canon EOS 5D Mark II, EF 16-35mm f/2.8L II USM, 1/200 sec at f/16, ISO 400.
