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

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