Chaga, Inonotus obliquus (Ach. ex Pers.) Pilát is a conk living on birch trees throughout the northern hemisphere. It is considered a sterile conk, but does produce small fruiting bodies that appear after the tree has fallen down, for up to six years. It has been widely used in folk medicine in Russia, Poland and other Baltic countries for a wide variety of gastric problems, cancer, tuberculosis, as well as heart and liver concerns.

Did you hear the one about the fungus and the algae?
They took a “lichen” to each other.

Lichen comes from the Greek leiko to lick or lick up, a habit of the “plant” to lap its tongue all over the host. However, “lichen” may come from the Greek “leprous, wart or eruption,” as Dioscorides thought they resembled the skin of afflicted people, and used the Doctrine of Signatures as an attempted cure. The French scientist, Tournefort named them around 1700 AD.