Fuscoporia obliqua
Which they say grows on Silver Birch.  Maybe they mean that they studied the mushroom that was found on white birch. The experts are using the old name for Inonotus obliquus here.  I think they are not keeping up with the changes in the scientific names or these articles were written before the name change.  Another example where there is an advantage of using the Russian common name Chaga.  It is generally known that this mycelium conk has similar medical properties whether it is found on White, Yellow or Black Birch.  In the first article it states that this mushroom grows in Asia.  It grows anywhere there is a winter.  It has been reported in Russia, Scandinavia, Alaska, Canada and the USA.  It is common here in Massachusetts.  Also in the first article it states that it grows on top of Silver Birch.  This could be a translation error since it does not grow on top of the tree.  It is found growing from the surface of the main trunk anywhere from ground level up.
Fuscoporia obliqua, as a traditional herbal medicine

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