Never Mind the Burdocks, a Year of Foraging in the British Isles: Spring Edition - March to May: Spring edition/March-May by Emma Gunn (Paperback, 2015)
Absolutely brilliant book recommended to me by a friend. I can't wait for the summer edition to come out too, then I will have the full set!
Has detailed pictures, descriptions, some recipes, and general interesting information, really ace!