Some years, the flowering of all the blackthorns is synchronised. Blackthorn hedges briefly look, from a distance, like they are covered in some kind of white foam.
In other years, like this one, the process is more spread out. Some sections of hedges like the one in the Barley Field will be fully out, while other sections have buds which are just developing.
These pictures are all from that hedge in the Barley Field, and cover just over one week in April.