Lichen is a special association between a fungus and an alga.
The fungus forms the main body of the lichen, providing an upper surface that protects the alga underneath, while the alga manufactures food using the energy of sunlight (photosynthesis). Each lichen has its own distinct species of fungus, but all lichens share just a small number of algae species; in most cases this is a green alga.
These are amazing small plant like structures found on a range of surfaces ranging from rocks and boulders to gravestones and the bark of trees. They are renowned indicators of air quality, superb sources of dyes and can even tell us about the acidity or alkalinity of the habitat in which they are found.
Lichen Identification Courses
Find out about bursaries for natural history courses including lichen identification courses.
Lichen Identification Resources
FSC Churchyard lichens Identification Guide will help you identify over 50 of the commonest lichens found in churchyards in Britain. The lichens are grouped according to growth form. Text on the reverse side includes guide simple illustrated lichen identification keys
FSC Lichens of heaths and moors identification guide will help you identify 62 of the commonest lichens from dry sandy heaths to wet peaty moorland.