Rock tripe
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Image:Umbilicaria sp.jpg
Umbilicaria growing on a rock
Rock tripe is a lichen of the genus Umbilicaria that grows on rocks. It can be found throughout northern parts of North America such as New England and the Rocky Mountains. It is edible when properly prepared and has been used as a food source in extreme cases when other food sources were unavailable, such as by early American northern explorers. It is commonly used as foods in East Asia.
