Chaga Mushroom is parasitic on birch and other trees.

The sterile conk is irregularly formed and has the appearance of burnt charcoal.

It is not the fruiting body of the fungus, but a sclerotia or mass of mycelium, mostly black because of the presence of massive amounts of melanin.

The fertile fruiting body can be found very rarely as a resupinate (crustose) fungus on or near the clinker, usually appearing after the host tree is dead.

I. obliquus is found most commonly in the circumboreal region of the Northern Hemisphere. 

It is distributed in birch forests in Russia, Canada, Korea, Japan, Eastern and Northern Europe, Alaska, the northern areas of the contiguous United States, and in the North Carolina mountains.

Generally found growing on Birch trees, it has also been found on Alder, Beech, Oak and Poplar.

Chaga is traditionally grated into a fine powder and used to brew a beverage resembling coffee or tea.