A lesson in lichen

One of my most asked questions is about lichen




Lichen are not plants neither are they animals.  They are a unique organism that is a combination of fungi and algae. Lichen are one of the oldest land dwelling life forms. They have adapted to live everywhere on earth from the arctic to the desert. Lichen are a combination of life forms which are mutually beneficial. The fungus has captured  the algae and protects it while the fungus receives nutrition from the algae.
Many cultures rely on lichen for food or medicine and other species like caribou eat it in winter as their main source of food.  Flying squirrels and hummingbirds use it for nesting material. A form of desert dwelling lichen was actually the Manna in the desert from the bible.  It is a variety that lays flat on rocks and sand but in the morning when the dew gets on it it puffs up and can appear to come out of nowhere.

The lichen we see mostly here in the northeast grows like shaggy beards on the branches of our trees. So many people ask me how to get rid of them.  Don’t! is the answer I give. Lichen do not damage the surface they are attached to nor do they take nutrition from them  They get nutrition from the algae and from particles in the air and water vapor. They are indicators of the quality of the environment. Where there is air pollution here aren’t any lichen.  They have been wiped out from many places due to poor air quality so if you see them that is a good sign for the area.  The Clean Air Act has done so much for improved air quality so that some places without lichen are not polluted any longer but it can take them hundreds of years to reestablish so we may not ever see them back in those areas in out lifetime.

So, my best advice is live and let live.  If you can get a magnifying lens and examine them up close I think you will get a greater appreciation of this unique life form


March 9th, 2017

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