Hypogymnia physodes. Photo by Ralph Pope.

There are approximately 3,600 species of lichens in North America and those are just the ones we know about! New discoveries are being made every year. Lichens are found all across North America and all over the world. They are found in a vast diversity of habitats and climates, from the Sonoran desert on the Coronado National Forest, to the alpine tundra of Alaskan mountains on the Chugach National Forest, and in the tropical rainforests of the El Yunque National Forest in Puerto Rico.

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.

Welcome to the world of lichens on our national forests and grasslands!

Sclerotia veratri, a cup fungusWhat are lichens?
Learn to recognize lichens

Alectoria sarmentosa, witch's hair, on Douglas-fir treesWhat Lichens Are Not
Know the difference between lichens and other plants

lichen-draped tree on the western coast of the United StatesWhy are lichens important?
Reasons why lichens are important

Xanthomendoza mendozaeLichen Biology
Learn about lichen structure, growth forms, and reproduction

Letharia vulpina, wolf lichen, on tree barkLichen Habitat
What are lichens' growth requirements?

lichenologist using a hand-lens to identify a lichenIdentification
Find out about collecting and identifying lichens

adult hummingbird with its young on a nest made of lichenDid You Know?
Fun facts about lichens and their use

Cladonia cervicornisPhoto Gallery
Explore the forms and variety of lichens

Map of the United StatesLichen Viewing Areas
Lichens can be found on our national forests and grasslands

Peltigera collinaLichen Glossary
Find definitions of lichen-related terms