Christensen, S. N. 2018. Lichens of Picea abies forests in Greece. – Herzogia 31: 219–230.
Twenty-six epiphytic and 12 epigeic species are reported from oroboreal Picea abies forests in the Rodopi Mountains, northern Greece. All species except Usnea intermedia also occur in the boreal zone of northern Europe and most inhabit a broad range of climatic zones. Conservation aspects of the forests are briefly discussed. Six taxa, Bryoria nadvornikiana, Cladonia subulata, Fellhanera subtilis, Peltigera hymenina, Ramalina obtusata and R. thrausta, are new to Greece, and two, Usnea intermedia and U. subfloridana, are new to Macedonia.