Lichens are valuable indicators of air quality (more pollution, fewer lichens) and they are also food, nest material, and shelter for birds, insects, and other wildlife. I knew that much, but until I started photographing them I had no idea how many they were, and how many trees and rocks are covered with a "bodysuit" of lichens.
http://pics.livejournal.com/e_moon60/gallery/00051ked
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