The black “beard” you see hanging from the branches of this birch has got really nothing to do with Treebeard – the ent – from Tolkien’s “Lord of The Rings”. It is called “treskjegg” in Norwegian – directly translated: “Treebeard”. It is actually one of extremely many species of Lichen (pronounced “lai-kenn”. Lichens are actually a symbiotic organism that consists of fungi and algae. The fungi provides proteines, salts and shelter. The sheltering structures contains, in addition to the fungus cells, algae-cells. The algae has chlorophyll and thus it produces sugar which it feeds to the fungus. A tiny ecological system in it self.
My friend Gunnar has studied lichens for a long time for The University of Tromsoe. Lichens are very sensitive to the environment and mapping lichens in a specific area, species, how much there is of the various species etc., is a very precise indicator of environmental changes; climate, acidity and pollutants. Any change in these paramaeteres can quite quickly be registered in the compositions of lichens, and thus has become a very interesting field in Biology and Ecology.