Wilde's book is an accessible primer to foraging in the UK, spanning the technical aspects of plant identification to ways of using foraged plants in everyday life—turning conkers into soap and sage into hair dyes are only some of FREE FOOD's intriguing tips. Wilde's enthusiasm for this subject is infectious, as are the way her descriptions bring her often obscure ingredients to life (the spicy seaweed pepper dulse, when incorrectly prepared, will apparently leave your house "smelling of tear gas at an XR rally"), and the book helpfully comes with diagrams and informational tables for foragers to refer to.
However, I'll also note that the book has a rather odd textual detail that slipped through editing: a sentence about the antimicrobial properties of birch ("A Finnish fisherman [...] back to port") is repeated in its entirety on pages 181 and 272.