Lichens

Lichens, the usually gray-green scaly growths found on many trees and on other substances do not harm the trees. They are a symbiotic, (mutually beneficial), combination of an algae and a fungi and the only thing they need a tree for is support. All of their needs are met from the air or the photosynthetic processes of the algae. 

Many people who see lichens on a tree are alarmed and think that the lichen is killing the tree. If a tree is dead or dying and covered with lichen it is only a coincidence, the lichen is not the cause. Lichens may grow on anything that is standing still, including rocks and metal. Lichens help break rock down into soil, as they creep into tiny crevices in the surface and expand them.

There are many species of lichens, the color and form may vary from the common gray - green lacy growths found on trees.  Lichens only grow where the air is not heavily polluted so if you have an abundance of lichens in your area be happy.

Lichens are eaten by many mammals including caribou, deer, antelope, moose and flying squirrels. Over 50 species of North American birds use lichens for food, nest building, or other uses.  Hummingbirds often stick lichens on their mud nests to disguise them.  Many species of insects, amphibians and reptiles use lichens as food, hunting grounds and homes. Lichens are a valuable and interesting part of natural systems and should be protected.