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Lichens

Lichen of different colors growing on the surfact of a rock.
Pleopsidium flavum. (Photo by Larry St. Clair)

Lichens are interesting organisms. They are diverse, adaptable, functional, and little understood. They play an important role in our natural ecosystems and can let us know when those ecosystems are in trouble. Lichens are beautiful, especially when you view a lichen-drenched Douglas-fir or a colorful crust-covered cliff, and up close when viewed under a hand-lens or microscope.

 

  • About Lichens

    Hypogymnia physodes lichen covering a thin tree branch.

    Learn to recognize lichens, the difference between lichens and other plants, and why lichens are important.

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  • Lichen Biology

    A closeup of acarospora-badiofusca lichen.

    Learn about lichen structure, growth forms, and reproduction

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  • Lichen Habitat

    A light green lichen growing on rough and pitted wood.

    What are lichens' growth requirements?

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  • Identification

    A person outside in what appears to be a high desert, holding a loop to his eye and looking closely at the surface of a small stone.

    Find out about collecting and identifying lichens.

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  • Did You Know?

    A hummingbird resting on a nest made from lichen while baby chicks wait to be fed.

    Fun facts about lichens and their use

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  • Photo Gallery

    A closeup of a batch of tall Cladonia Cervicorni lichen.

    Explore the forms and variety of lichens

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