High pollution

Common orange lichen (Xanthoria parietina)

The common orange lichen (Xanthoria parietina) is one of the rare species of lichen that tolerates polluted air, so it can be found in populated areas on the walls of old buildings, concrete fence posts, stone monuments, and other surfaces, but it also thrives in forests on the trunks of deciduous trees. Lichen thallus is similar to a greenish-yellow or orange, scaly bark. The common orange lichen likes nitrogen-containing compounds and well-lit areas. There are usually many rounded fruiting bodies or apothecia on the surface of the thallus. The colour of the thallus is affected by the growing conditions – in shady areas it is not as bright as in well-lit areas.