Ireland's oceanic and temperate climate acts as a wonderful host to over 1,165 species of lichen. This is a richer biodiversity than that of flowering plants or the mosses, liverworts and ferns of Ireland. A concise introduction to lichen biology and ecology, this guide features: * lichen terminology explained using line drawings and photographs; * descriptions of over 250 Irish species with colour photographs; * a guide to chemical tests, fieldwork and how to keep a herbarium; * a vice-county distribution map for every described species.