Mushrooms

What are mushrooms and toadstools?

‘Venomous and muthering’, ‘evil ferment’, ‘poysononous damp weeds’. Few people of the past had a good word to say about fungi and, until the early eighteenth century, no one had the faintest idea what these ‘earthie excrescences’ actually were, though this did not stop people making something up. Fitting uncomfortably into the more familiar world of plants and animals, these mysterious agents of putrescence, decay and sometimes death have always been treated with great suspicion. But, practical people as they had to be, the ancients sensibly classified the fungi into two important groups: the ‘esculenti’ and the ‘perniciosi’. This attitude, shared by this present book, was neatly expressed in the sixteenth-century Grete Herball, where we find the best known of all fungal quotations:

‘Fungi ben mussheroms; there be two manners of them, one maner is deedley and slayeth them that eateth them and be called tode stoles, and the other doeth not.’

These pretty words go most of the way to answering the question I am asked most often after ‘Can I eat it?’ – ‘What is the difference between a mushroom and a toadstool?’ I thinkg that the simplest differentiation is this:

‘A toadstool has a cap and a stem and you can’t eat it, a mushroom has a cap and a stem and you can.’ Slayeth and doeth not.

Much has been written about the derivation and meaning of the words ‘mushroom’ and ‘toadstool’ and little agreed upon. ‘Mushroom is from the Old French ‘mousseron’, itself derived from ‘mousse’, which means ‘moss’ and is probably a reference to the soft texture of most fungi. The word ‘toadstool’ is very likely no more than it seems; the ‘toad’ part reflecting a perception of that animal’s poisonous nature and the ‘stool’ a simple reference to shape. ‘Toadstool’ has sometimes, as above, been rendered as ‘tode stole’ with ‘tode’ being the German word for death. Whichever derivation one accepts, it is clear that ‘toadstool’ is a pejorative term, while ‘mushroom’ is not. There is a narrower definition that is very useful, though it can contradict the first one:

‘A mushroom is a member of the genus Agaricus.’

The genus Agaricus includes A. bisporus, A. campestris, A. arvensis and A. silvicola, the Cultivated, Field, Horse and Wood Mushroom respectively, so you can see some sense of it. Indeed, the term ‘the true mushrooms’ is often used for Agaricus species. The contradiction exists because there is also A. xanthodermus, the Yellow Stainer, which is poisonous. A pity, really. One last word on etymology: the word ‘fungus’ is derived from ‘spoggos,’ which is Greek for sponge. By this time, most of my enquirers have regretted their question.

While there will always be more to learn, the essential nature of fungi has now been firmly established. Their inexplicable ability to appear suddenly in the same spot year after year, without apparent roots and sometimes in those mysterious rings, is now all explained. Mushrooms and toadstools – and most of the many other fungal forms one sees in the woods and fields –  are not organisms. They are organs. The bulk of the organism is underground (or within some other sub-stratum, such as wood) and takes the form of microscopically thing (about a tenth of the diameter of a human hair) fibres called hyphae. These form a largely invisible, but nevertheless huge, cotton wool-like mass called mycelium. Our mushrooms and toadstools are, quite simply, the reproductive organs, the fruit bodies, or this larger organism; their sole purpose is to produce can disperse spores. Billions of them.

So now we understand that mushrooms and toadstools grow quickly because all of their raw materials are ready and waiting in the mycelium, and they grow in the same place year after year because that is where the actual organism is situated. Mushrooms and toadstools do have the equivalent of roots, but they are usually too thin to see and they sometimes form rings because the mycelium from which they spring grows outwards from a central point and dies off in the middle. No lightning, no dragons, no pixies.

Early writers were correct in their assessment that fungi fitted poorly into the world of plants and animals. Fungi are neither. They inhabit their own great kingdom – Kingdom Fungi – which now sits alongside the other great kingdoms – Plantae, Animilia, and two or three more.

Organisms belong to their particular kingdom simply because their parents did,  and not because they have certain characteristics (in the same way dolphins still wouldn’t be fish even if they looked twice as fishy as they do). Nevertheless, fungi do have certain properties which, taken together, distinguish them from members of the other kingdoms. Their cells are, in fact, the hyphae mentioned above and, unlike most plant and animal cells, need many nuclei scattered along their length to control the various cell functions. The cell walls are made not from cellulose as in plants, or proteins as in animals, but of chitin, a material more familiar as the crunchy bit of cockroaches. Their most important property viewed form an ecological viewpoint is an inability, shared with all animals and a very few plants, to make their own food. They either externally digest organic matter and absorb the resulting simple, soluble soup through their cell walls, or are provided for by plants with which they have formed a symbiotic relationship.

As with plants and animals, fungi are divided into family groups. Of the major divisions of the fungi there are two that interest the mushroom hunter – the Ascomycota and the Basidiomycota. The former contains species as diverse as Truffles and Morels; the latter contains most of the rest of the species in this book. They are sometimes more approachably called the ‘spore shooters’ and the ‘spore droppers’. These names are references to the hugely complex microscopic mechanisms by which the spores are formed and released.

I do hope that some of the excitement and wonder of mycology rubs off on you as you search for your supper.