The thallus of Evernia prunastri appears fruticose, though is technically foliose due to the differing of the upper and lower surfaces in color, the upper being green-yellow and the lower whitish. The texture of the erect to drooping E. prunstri is very soft and pliable. The thallus measures 7 to 13cm in length and branches dichotomously each year, allowing the age of the lichen to be determined by counting the number of continuous branch points. Reproduction is achieved asexually via soredia, sexual apothecia have not been observed.
The typical substrate of E. prunastri includes the wood or bark of hardwood trees and shrubs, sometimes of conifers, in the shade or sun.
Occurance of E. prunastri is common west of the Cascade Mountain Range and spradic on the eastern side extending into western Montana. West of the Cascades, E. prunastri is found in savannas and urban or agricultural areas. The occurance becomes less common in lower mountain forests. East of the Cascades, only riparian forests and shrubby areas are inhabited by E. prunastri. The distribution is restricted to the west coast of North American and is common throughout Europe.
In Europe, E. prunastri is commercially important for use in perfumes as a fixative. At one point in history, thousands of tons of E. prunastri were collected per year in order to supply the cosmetic industried of Slavic republics. The abundance of E. prunastri has never been high enough in North American for use in the cosmetic industry. At the present time, the lichen thallus is shipped from Macedonia to France for commercial use. In Egypt, it is used as an additive in bread.
Brodo, I.M., S.D. Sharnoff and S. Sharnoff (2001) Lichens of North America. Yale University Press, New Haven, Connecticut.
McCune, B. and L. Geiser (2009) Macrolichens of the Pacific Northwest. Oregon State University Press, Corvallis, Oregon.