title: Umbilicaria esculenta
text: # Umbilicaria esculenta
  
  Umbilicaria esculenta, the rock tripe, is a lichen of the genus Umbilicaria that grows on rocks.
  
  ## Morphology
  
  Two different types of polysaccharides are known to be the structural components, both a heteroglycan from the fungus and a glucan from the alga. U. esculenta lichens have a thallus attached to the substrate with a central holdfast. The thallus is also heteromerous (parts that are different in quality and number) and fully corticated (has a cortex and bark). Many of the Umbilicaria species are characterized by a veined or rugose thalline surface.
  
  ## Ecology
  
  Umbilicaria esculenta is a saxicolous lichen; it grows on rocks and is known widely as the "rock tripe". It is usually found on at high altitude in East Asia.
  
  ## Human uses
  
  Lichens have a history in folk foods. U. esculenta is considered a delicacy where it is eaten in dishes, soups, or in salads. It has been used as starvation food by Native Americans and early settlers.
  
  ## Gallery
  
  * Iwatake gathering at Kumano in Kishū, by Hiroshige II
  * Korean pan-fried Umbilicaria esculenta
  