Usnea – Old Man’s Beard
This lichen, and other members of the Usnea genus, can often be found growing on the branches of less than healthy trees in the Northeast. The algal component of these algae/fungi phenomena takes advantage of the lack of leaves on dying trees by using the available sunlight to photosynthesize. Usnea, also known as Old Man’s Beard, grows in little hair-like tufts and has a diagnostic pale yellow, elastic central cord. In addition to being an indicator of air pollution (its size is greatly decreased if there is pollution), Usnea has been used by herbalists as an immune system tonic for hundreds of years.
Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.