Usnea

Usnea australis

The genus Usnea Lichen ( Usnea ) includes lichens, which grow mostly hanging from trees. Many species are known as old man's beard or Treebeard and are gray or greenish.

Features

Beard lichens are bush - up beard shaped shrub lichens with round, thread-like branches; they are gray to greenish yellow. The bearings are usually five to ten centimeters long and are only grown in one place. However, in mountainous areas with clean air they can achieve much greater lengths; in areas with higher air pollution they are shorter. Are located on the threads often hemispherical to pin-shaped outgrowths. You can break or wear sorediös isidia. After pulling the strands initially tear on only the cortex and medulla, so that the central white medulla is exposed. Apothecia are very rare in some species, but may be present regularly in some, with good progress.

Types (selection)

• Usually Treebeard (U. filipendula )
• Pitted barber's itch (U. hirta )
• U. barbata
• Disk Lichen (U. florida )
• U. longissima
• U. dasypoga.

Ecology

Beard lichen growing on coniferous and deciduous trees with sour bark. You prefer, rainy and cold layers of air areas.

Special

In some species, the antibiotic usnic acid was discovered, which is now produced synthetically. In the highlands of South America a gesteinsbewohnende type is used as a tea for coughs.

Similar genera

Among the shrub lichen Usnea are characterized by their filamentous (not ribbon-like ), greenish stock. The genus Bryoria has brown to gray yarns; also lacks the white central strand.