The Usnea lichens are usually found on trees and shrubs, but you can also see them on wooden posts and railings. They like to grow where they can get lots of sunlight.
The growth form shown by these species is known in "lichen language" as fruiticose , ie it is bushy. In the Usneas, the stems are round and pendulous (hang downwards).
The Usneas are often referred to as "Old Man's Beard"