Identifying Edible and Poisonous Wild Mushrooms. There are roughly 15,000 types of wild fungi in the UK. Our guide aims to help you identify the best to eat and the most important ones not to pick. Never rely on one source for mushroom identification, and never eat anything unless you are 100 sure it is edible.. - Guide to British fungi: where to find and how to identify. Oyster mushroom. Chicken of the Woods. Giant puffball. Penny bun/porcini. Chanterelle.gy inkcap. Jelly ear. Fly agaric..Unfortunately there are no golden rules when it comes to identifying unfamiliar mushrooms, edible or otherwise. Deadly poisonous toadstools can share the .