The birch polypore is a common bracket fungus and, as the name suggests, grows almost exclusively on birch trees. The brackets burst out from the bark of the tree, and these fruit bodies can last for more than a year. Technically, it is an edible mushroom, with a strong, pleasant "mushroomy" odor but a bitter taste. It has long been known that the Birch Polypore has medicinal uses, it has been used as a tonic for the immune system, as an antiseptic to clean wounds and promote healing, a plaster that is microporus, antifungal and antiseptic and probably by stone age man to get rid of parasitic worms.
 
Maine Wild Strain cloned from the mushroom pictured above