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The edible species greatly outnumber the poisonous, although there is of course a considerable variation in their taste value, ranging from such epicurean delights as the Cep (Boletus edulis) or the Morels (Morchella species) to the equally edible but rather bland species which will form the bulk of a day's collecting.

It is only when you start to branch out into the more obscure species that mistakes are liable to happen, and mistakes in fungi co1lecting can have fatal results. Many collectors think they are safe if they stick to the true wood and field mushrooms, the various Agaricus species. By doing this they run the risk of collecting some of the not so edible 'doubles' that exist. If they had kept instead to the more exotic, but therefore more easily recognized, favourites - the boletes, parasols and morels - such mistakes would almost certainly not have taken place. The common Field Mushroom can be surprisingly difficult for the beginner to identify properly and victims of the Death Cap are on record as saying that they picked it because it looked like a mushroom. The rules mentioned in the last chapter are even more important when you intend to eat your finds. To collect the fungus intact and so reveal any telltale signs such as a volva is vital for accurate identification.

The golden rule is: if you are at all unsure of a mushroom's identity, don't eat it.

Most fungi are best eaten young, but do not collect 'buttons' which are too small to identify accurately - they may belong to another less edible species. Ideally you should at first stay with the five or six really well-known and delicious edible species: the Cep, Morel, Parasol, Shaggy Inkcap, Chanterelle and Black-Trumpet (Craterellus). These are alI very distinctive and even a beginner can soon recognize them very quickly. Once you are thoroughly acquainted with these, you may then wish to go on to try some of the many other popular edible species, such as the Beefsteak Fungus (Fistulina hepatica), the Oyster Fungus (Pleurotus ostreatus), the Blewits (Lepista nudum), Lactarius deliciosus, and the many edible species of bolete. It is a great advantage if your initial trips are with a mycological society or other experts who can identify these at first hand and show you their distinguishing features in the field.

When you have your fungus identified and ready for cooking, do make use of a good cook book. There are several specialist fungi books available, and they really are useful ; a mushroom cooked incorrectly can end up quite tasteless and you may never realize its full potential. If you are stilI dubious about collecting your own food but would like to try the more unusual kinds, you can often find canned or dried fungi in Italian, Chinese or Japanese food shops and these are, of course, quite safe!

Fungi are usually eaten as a vegetable rather than as a main dish, for their great virtue is complementing and bringing out the flavour of other foods. They are particularly good with meat, but they are also a valuable addition to stews, soups and omelettes, and as an ingredient in stuffings, sauces and hors d'oeuvres. Nutritionally the boletes in particular provide significant amounts of protein, and many species also contain useful vitamins (B, D and A), as well as various trace elements and minerals. It is known that people and animals have survived for extensive periods on fungi alone with no ill effects, sometimes even gaining in weight!

In preparing fungi it is important to examine them carefully, remove any dirt or insects, and cut away soft or rotten portions of the fruit-body. A slice down the centre of the fungus will reveal any insects or larvae within; unfortunately insect attack is fairly likely, especially in the more mature fruit-bodies. Do not wash them more than is absolutely necessary - usually a wipe with a cloth will suffice. Only peel the cap where the skin is very thick or has a glutinous surface; scales are usually left on as they normally vanish with cooking. Whether or not you eat the stem depends on the species and how tough it is; with tender species you will only need to cut off the base and remove any soil.

Do not eat too many fungi at once, particularly if you have never eaten that species before. Many people find even the best edible species rather indigestible and some unfortunates are allergic to all fungi and can become quite ill or develop a rash. So wait until you are sure of your body's tolerances.

The fervour and enthusiasm which many people have for eating fungi can seem quite amazing to those who do not indulge, and to accompany a group of devoted mycologists one might think that precious gems were at stake! Particularly where the Morel is concerned, competition is very strong, and in Europe, where the truffie commands a high price, a man with truffles on his land is a very wealthy man indeed.

Although it is to be hoped that encounters with poisonous fungi will not be in a meal, they are nevertheless a fascinating group of plants and anyone intending to eat fungi must become acquainted with them. The various toxins contained within the fungus vary in their chemical make-up and in their effects upon man, and because of this it is possible to group the poisonous species according to the toxins they contain.

Firstly comes the most complex and deadly of the toxins and hence the most infamous of the toadstools. These are the various Amanita species and in particular the Death Cap, Amarita phalloides, and the Destroying Angel, Amarita virosa. These two species, along with one or two close relatives, cause a high proportion of the really serious and often deadly poisonings each year. The toxins contained in the fruit-bodies of these fungi are unequalled for their complexity and their lethal qualities; recent research suggests the presence of up to eleven different, closely related poisonous chemicals belonging to two principal groups - the phallotoxins and the amatoxins, the two groups of poison differing in their effects and in the time they take to attack the body. One of the difficulties with treating Death Cap poisoning is that it usually takes six to fifteen hours, sometimes even longer, before the symptoms appear and by the time the symptoms are apparent it is too late to use a stomach pump as the poisons have already entered the bloodstream. The effects of the poisoning are long and painful, with severe gastric and abdominal pains accompanied by violent vomiting. lf treatment is not obtained death will occur within three to five days, and post-mortem examination normally reveals severe liver and kidney damage. The exact workings of the toxins are stilI not fully understood, although it is known that they are not filtered out of the body by the kidneys as are other harmful substances, and that they attack and break down the walls of the body cells as well as causing the gastric upsets. Until recently, in the absence of a completely successful antidote the only treatment was to attempt to counteract the symptoms as they occurred. In some recent cases, however, the use of the drug thioctic acid and of artificial kidney machines (blood dialysis units) has had notable success and it appears that we have at last found an effective treatment for Death Cap poisoning.

Luckily such deadly poisons are rare within the fungus world and only a few other toadstooIs are known to contain them. Two which have caused some poisonings are Galerina autumnalis and the closely related species Galerina marginata (unicolor). These two rather small brown mushrooms are thankfully not very common and are usually passed over by collectors as being too smaII to eat. But they can be mistaken for edible species, in particular Galerina (=Pholiota) mutabilis which is commonly eaten; both species have a ring on the stem, and are rather similar in generaI appearance.

Although the majority of the species of Amanita seem to be more or less poisonous, not all of them contain the same poisons as the Death Cap, and two particularly welI-known species have a different sort of poison altogether. These are the Fly Agaric, Amanita muscaria, and the Panther Cap, Amanita pantherina, which are but two of a whole range of fungi containing the poison muscarine. This poison is also widely distributed in the genera Inocybe and Clitocybe, some of which are even more potent than the two amanitas. The effects of muscarine poisoning are not usually fataI except when it has been taken in very Iarge doses; the normaI reaction to eating one or two of these fungi is a reduced heart rate, giddiness and blurred vision, sweating and difficulty in breathing, as well as stomach cramps and vomiting. The poisoning is further complicated in the Fly Agaric by the presence of another type of drug, this time an hallucinogen, musrazone. Hallucinogenic drugs of one sort or other are curiously quite frequent in fungi, and the genera Psilocybe and Panaeolus both contain chemicals that effect the brain in a very similar fashion to the now famous drug L.S.D. The fungus Psilocybe semilanceata, a very common grassland species was recently [ed. note: in the 1960s or 1970s] the subject of a court case where a man was charged with being in possession of a dangerous drug. He was found not guilty, the judge deciding that being in possession of a drug and being in possession of a mushroom, albeit containing a drug, were two different things! Needless to say the use of any of these fungi for their hallucinogenic properties is highly dangerous, as most of them also contain the poison muscarine, along with other suspect chemicals.

A rather strange reaction is caused by the species Coprinus atramentarius, but what is even stranger is that the reaction only occurs after alcohol has been drunk with the meal. When this reaction was first reported it was realized that it was very similar to that of a drug used in treating alcoholics, Antabuse, which causes an unpleasant reaction every time the patient has a drink. The exact identity of the chemical in the fungus had long eluded scientists and the exact conditions necessary for poisoning to take place were uncertain, but Swedish researchers have recently isolated the chemical, which they calI coprine, and it seems likely that the reaction only takes pIace if the fungus is cooked. The symptoms, although not serious, are distressing and involve an intense flushing of the face and neck, together with an increased pulse rate and a feeling of great heat. These symptoms usually fade quite rapidly, although they may return if more alcohol is drunk.

One of the most remarkable toxins is surely that contained within the False Morel, Gyromitra esculenta. From its species name you might infer that this is a very choice edible species and indeed it is widely eaten in Europe. However, cases have occurred, some of them fatal, of poisoning caused by this very same fungus. The answer to this strangely variable reaction, which has puzzled mycologists for some time, lies in the fact that it contains rocket fuel! Impossible as it may seem, Gyromitra esculenta naturally produces a chemical called monomethylhydrazine which is manufactured by man as a rocket fuel. This chemical compound has a boiling point of about 87°C, so that if the fungus is first boiled in water at 100°C the poison will be evaporated out of the tissues. However if the temperature is not high enough or the fungus is not cooked long enough then enough poison can remain to cause serious harm.

Finally, there are a number of species which can cause severe gastric upsets, although not usually anything more serious. These include many of the Russula and Lactarius species (although these are usually rendered harmless after cooking), and various species of Tricholoma, Boletus and even Agaricus. The latter may seem surprising when you consider that Agaricus hortensis, the cultivated mushroom, provides us with our principle fungus food. One Agaricus species in particular seems to cause trouble - Agaricus anthodermus, the Yellow-stainer. As its name implies, this fungus stains vivid yellow, particularly when the flesh is broken at the base of the stem, and although many people can eat this species quite safely others are made very ill indeed. The yellow stains and rather flattened, slightly scaly cap are usually quite easily detected and separate this species from the common Field Mushroom, Agaricus campestris.

As well as the danger from these different types of poisoning, you must also remember that like other vegetables the fungi are susceptible to decay and to avoid the risk of food poisoning they should only be used when they are fresh. Avoid any fungi that have been caught by frost, for species which are otherwise quite edible can suddenly prove dangerous. If alI these warnings of poisoning sound alarming, remember that the truly poisonous species are very much in the minority and that with common sense and strict identification you can enjoy some of Nature's most subtle flavours, not only good food but free food!

Source:

"To eat or not to eat", Geoffrey Kirby, Mushrooms and Toadstools, Chartwell Books Inc./Mandarin Publishers Ltd. (Hong Kong, 1977), p. 81-83.
Photo (top): Andre Mohovičić & Daniel Načinović, Istria, terra magica, Otokar Kersovani, Laurana (Zagreb, 1994).