What is a lichen, how does it live, uses of lichen by man. Organic lichen indicator of clean air and healthy forests.

Of the 20,000 species that can be found in the world, 11,000 are present in France, which means that they can be observed everywhere, from the most arid deserts to coastal areas flooded by the tides.

This formidable symbiosis between a fungus and an algae makes lichen almost indestructible, except, for many species, to pollution caused by man.

Used in medicine for thousands of years, for food, in the manufacture of dyes, perfumes, and construction materials by birds, lichen is today at the heart of research into biofuels.

There are so many great stories to tell about this organism that has been on earth for over 600 million years.