Chaga – the black gold of Nordic forests
Clinker polypore or chaga is one of the most known medicinal fungi that mainly grows on birch trees but can also be found on alders. Therefore, it is also known as birch canker polypore, which in fact is a completely different mushroom (Piptoporus betulinus). The internationally known name “chaga” comes from “чага”, its name in Russian.
Clinker polypore (Inonotus obliquus) or chaga has been used in folk medicine for thousands of years already thanks to the beneficial effects it has on human health. The most common treatment is drinking infusions made from chaga. Today, you can find chaga as elixirs, extract and capsules to be consumed as food supplements.
Chaga is a powerful antioxidant that increases the organism’s resistance and prevents diseases. Various global studies have shown that chaga has health benefits in case of cancer, viruses, bacteria, diabetes and inflammation. Additionally, it supports and improves the microbiome balance in the gut, lowers blood sugar and cholesterol, slows down the organism’s ageing processes, strengthens the nervous system, relieves stress, anxiety, insomnia and even improves memory. Chaga contains large quantities of various B group vitamins, flavonoids, phenols, minerals and enzymes. Flavonoids have antioxidative and phenols antiseptic properties. In conclusion, using chaga improves removing toxic substances from the organism.
Growing chaga as a great investment
Nowadays, people’s knowledgeability about keeping themselves healthy and protecting their health has increased and therefore the demand for chaga has also increased. More and more forest owners try growing this mushroom on birch trees themselves. Growing medicinal fungi is becoming a natural part of the future of silviculture because growing mushrooms on trees help increase the value of those parts of the forest that aren’t valuable and earn income already in 5 years.
Chaga prefers to grow in areas with a cooler climate, such as North America, Russia, Siberia, Japan. In Europe, it is often found in Central and Northern Europe. Estonia is an ideal place for growing chaga because over a half of Estonia’s land territory is covered with a forest. Financially, it is the most reasonable to grow chaga in areas that have low fertility and/or are waterlogged where besides less valuable timber mushrooms can offer added value. 0.25-2 ha of forest is required for growing chaga. Grove forests, Sphagnum bogs and drained peatland forests are the most suitable.
It is very difficult for chaga to spread naturally because its spores usually only spread when the host organism, meaning the birch tree, dies. Therefore, wooden dowels that are colonised by the chaga mycelium are used, which are then planted in birch trees. Chaga dowels are planted when the diameter of the birch tree is at least 10 cm. The number of dowels per tree depends on the tree’s age and thickness, but usually 4-6 dowels are planted per tree. It is important not to damage the tree more than it is necessary for inserting the dowel. Increase the number of trees growing chaga rather than the number of dowels per tree. It is recommended to plant the dowels at the height of up to 2 metres, which enables the rest of the tree to be used as pulpwood or firewood after the chaga has been grown.
Birch trees produce a yield of chaga about three times every 5-7 years. Therefore, when you grow chaga, you need to take into account that you cannot cut this forest for 20 years.
The effect of growing chaga on the host tree and the forest
Currently, there is no information about growing chaga endangering the forest as a whole. This mushroom also spreads naturally – and for that to happen, wind and insects need to help as well and a new tree can become inoculated only through wounds on the tree’s bark.
It is known that chaga weakens the trees’ resistance and makes them more susceptible to pests and diseases. However, trees are weakened on a controlled territory, meaning where chaga is being grown, and the spreading of the fungus is complicated, needing the presence of suitable natural conditions, then the fragmentation of forests in Estonia (incl. species of trees of various ages in habitats) does not actually support it widely spreading. The mushroom is not a danger to seedlings or young stands because it prefers to inoculate primarily mature damaged trees. Forestry experts rather see that weakened or standing dead trees offer abundant (micro)habitats in nature, which even diversify the biota and contribute to the balance of the ecosystem.
Pick edible mushrooms and also mushrooms from trees from your forest
On living trees, chaga forms gnarly sponges with an indefinite shape, they have a black exterior and a rusty brown rubbery interior. The mushrooms can have a diameter from a few centimetres to half a metre.
Since chaga is a valuable resource, you need to follow environmentally friendly principles when you pick them. The best times for picking are autumn and spring when the trees don’t have any leaves. Chaga is collected from a living or recently cut tree because after the tree’s death, the chaga starts to disintegrate and its medicinal properties are lost. You should only pick chaga that has a proper size (leave the smaller ones to grow) and remove the mushroom carefully without damaging the host tree.
The chaga you picked needs to be cleaned carefully, cut into pieces of 5-6 cm, air-dried in a clean environment or in an oven at very low temperatures (max 50-60 ℃). The drying stage is very important so that there wouldn’t be any mould or rot (the humidity of the mushroom shouldn’t be over 14%). To store the chaga, keep it in a dry and dark place. This way, dried chaga can be stored for up to 3 years.
Interesting facts about chaga
Getting its name
The name of chaga in Estonian (must pässik=black ram) likely came from the fact that the black mushroom mass on the tree trunk is as hard as a black ram’s head. Chaga is also known as clinker polypore, black mass, cinder conk. “Chaga” comes from “чага”, its name in Russian.
The status of a herb
Chaga is a mushroom, yet it is classified as a herb. According to Chinese medicine, it is a tonic herb – it can be used in large quantities and for long periods of time. Chaga has been given the status of a miracle cure, which supposedly gives you the strength of a bear, the fertility of a hare, will cure you from cancer and will support the nervous system.