The field mushroom is the common edible mushroom — Agaricus campestris, the wild relative of the cultivated button mushroom. It fruits in pastures and lawns in late summer and autumn: a white-capped mushroom with pink-then-chocolate gills, a sturdy stem, and the familiar mushroomy smell. It is the mushroom of childhood foraging and of traditional country cooking — fried for breakfast, made into soup, pickled for winter. The caution is absolute: it has deadly lookalikes, notably the young destroying angel, and safe picking demands certainty about every specimen — spore print, gills, ring, and habitat all checked. The field mushroom’s cultivated cousin dominates the shops, but the wild original, gathered knowledgeably, remains one of the finest free foods of the countryside.