Butterfly blizzard

Summer 2009 saw an estimated 11 million painted lady butterflies surge north to Britain from the Mediterranean. In her bestseller Wilding, Isabella Tree describes how swathes of creeping thistles at her rewilded Knepp estate in Sussex (turn to page 67) disappeared amid a vast ‘butterfly blizzard’. Numbers of this large, migratory species usually peak between May and July – keep an eye on thistle, knapweed, ragwort and red valerian – and mass invasions occur roughly once a decade, so one is overdue.

FIND OUT MORE Visit ukbutterflies. co.uk and butterfly-conservation.org