physcia caesia, known colloquially as blue-gray rosette lichen and powder-back lichen, is a species of foliose lichenized fungus

soil frost leaf flower nature rock plant grass asphalt freezing water sand wildlife branch geology physcia caesia colloquially blue-gray rosette lichen powder-back species foliose lichenized fungus abstract amazing ascomycota background beautiful woman black blurry close closeup colorful detail environment family focus forest gray grey lens lichens macro moss mycology natural colors old orange organism outdoor pattern pollution rough stone texture tromso white fungus lichen