According to Wikipedia:
A mushroom is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground on soil or on its food sourceAs far as I could determine from another place in Wikipedia, the mushroom I found were of the type
Birch Bracket (Piptoporus betulinus - also known as Razor Strop) is one of the most common polyporous bracket fungi and, as the name suggests, grows almost exclusively on Birch trees. The brackets burst out from the bark of the tree, and these fruiting bodies can last for more than a year. Technically, it is an edible mushroom, with a strong, pleasant "mushroomy" odour but a bitter taste. It is said to have medicinal properties, and the velvety cut surface of the fruiting body were used as a strop for finishing the finest of edges on razors. Dried specimens have also been used as tinder, and this fungus was carried by "Ötzi the Iceman" - the 5,000 year old mummy found in the Tyrol.We seem to be in good historic company here. And it is also evident from the pictures here that this particular mushroom is very fond of birches.
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