The Black Birch Mushroom – Chaga
A strange and unattractive growth, dark bluish-brown, almost black, cracked and fissured, 40–50 cm in diameter, irregular in shape and not at all like a mushroom, sometimes weighing as much as 5 kg or more. It grows on living birches, more rarely on alders, rowans or other trees. Without an axe or a woodcutter's knife you cannot break it off or pull it off, only crumble its surface. Only in very rare cases does one manage to break off a larger or smaller part of it, a fragment. This fungus was noticed and described by mycologists almost 200 years ago.
More growths of various origins grow on trees, and this fungus is often confused with them. Most people know it: it is the black birch mushroom, the clinker polypore (Inonotus obliquus (Pers.) Pilat), also called "Chaga".
It is believed to cure all diseases. The spreading, woody, lumpy fungus is perennial, and its appearance is considerably influenced by sun, rain and wind. Nature gave "chagas" healing properties, thereby setting them apart from other polypores. This intricate part of the fungus consists of uneven, cross-striped layers and, most importantly, does not form or produce spores. It is a sterile form of the clinker polypore. In Lithuania only a few sites of the non-sterile form of the clinker polypore are known, but "chaga" (the sterile form) is quite common and can be found in many birch groves. So when going into the forest to look for the miraculous "chaga", you may make a mistake and cut off some other bracket fungus – these are often on the stalls at the market. On the other hand, it is possible to find genuine "chaga" at the market, but it may be old and worthless. "Chaga" is not such a miraculous fungus, although it is more valuable than other bracket fungi.
The first to take an interest in the biochemical and medicinal properties of this fungus was Prof. Dragendorff of the University of Tartu as early as 1864. He found nothing special and did not study the fungus further. There were no more thorough studies in other countries either. Only 100 years later, in 1964, did the medical institute of St Petersburg (then Leningrad) resume research on this fungus and take an interest in its medicinal properties. The institute established that this bracket fungus is extraordinary: it contains many biologically active substances – as much as 19 percent potassium and sodium, 2.45 percent magnesium oxide, 1.88 percent calcium oxide, and many pigments containing phenolic, oxyphenol-aldehyde, organic acid and other substances.
Apparently these substances are properly balanced and calm the central nervous system, improve metabolism and strengthen the immune system. Many began to regard this fungus as miraculous, but neither science nor practice has yet confirmed any extraordinary powers. Despite all the doubts, preparations such as befungin and bin-chaga have appeared. The ground fungus is recommended for treating certain diseases of the digestive tract, but when the disease is advanced, especially an oncological one, "chaga" is powerless, although for some patients it brings relief and even prolongs life. The black birch mushroom is used not only in medicine: attempts have been made to use it to improve fodder so that it stimulates the growth of livestock, especially piglets.
Only the fungus growing on birches is used for medicines and fodder. "Chagas" growing on alders, rowans, hornbeams and at the bases of old birches are not used. These fungi can be gathered all year round, but they are most valuable in winter and spring. At that time they contain the most biologically active substances. One can look for "chagas" in the forest even on the coldest winter day. For drying, the fungus is cut into 4x5 cm pieces. It cannot tolerate temperatures above 60 °C, so it is dried at a temperature no higher than 50 °C. Its active substances are retained for only 3–4 months, so it is not advisable to buy these fungi at the market, since it is unknown when they were gathered, at what temperature they were dried and on which trees they grew, and sometimes something other than this fungus is sold altogether. Dried and crushed "chaga" is kept in airtight containers in a dry place, protected from moisture and mould.
An infusion of this fungus, which contains a large amount of active substances, is used to treat chronic gastritis, gastric and duodenal ulcers and haemorrhoids; the infusion activates liver enzyme activity. Before using "chaga", even prophylactically as a tea, it is essential to consult a doctor.
Recently, ways are being sought to propagate this fungus artificially, since its natural resources in nature are small. In addition, sanitary felling in birch forests further reduces the stocks of "chaga", while the search for it is increasing.