Lichens don’t receive much attention in the macro world in comparison to flowers and insects. This is a pity because many are indeed photogenic, and the diversity among species in terms of colour and structure is amazing. They are a fascinating group of organisms and a familiar part of our landscape that for the most part largely go unnoticed.
These colourful organisms are at their best during the winter months when the trees are devoid of leaves and the moisture level in the air is higher. Many species have a colourful vibrancy to them at this time of the year, particularly after rain. Lichens are the result of a successful partnership between a fungus, an alga, a cyanobacterium, or both, existing together in a symbiotic relationship. The fungus provides the structure or the thallus as it is known and the alga, or cyanobacterium through photosynthesis provides the essential nutrients. This is a highly successful partnership that stems back millions of years. Many lichens are also sensitive to pollution and are important biomonitors, of the health of our environment. They grow in some of the most unlikely places and manage to survive in the most inhospitable places on earth.
The larger eye-catching species form patchworks of colour on rocks and decorate the trunks and branches of trees and gravestones. They also have many other applications and are used in medicines, perfumes and as dyes to colour wool and other fabrics. They are also an important food source for snails and slugs and many insects including the larvae of some moths. There are over 1700 species of lichen described in the British Isles and probably many more awaiting identification and discovery.
PHOTO 2 Ochrolechia parella Pertusaria pertusa & porpidia crustulata.
The ideal habitats
Most people are more aware of lichens in a coastal environment. The vibrant orange and yellow colours of the Caloplaca’s and Xanthoria’s are some of the most common species seen on weathered rocks. This a good place to begin your explorations. Old native woodlands also contain a large number of species, but a little more diligent searching of the trunks and branches of trees is required to find some of the most interesting species.
Some lichens form patterns and mosaics on certain trees such as Holly and Hazel. Heaths and bogs are good habitats for Cladonia species, which resemble redheaded matches and deer antlers. Old churchyards are also excellent habitats for crustose species; these are lichens that spread and embed themselves into the rock and cannot be removed from the surface.
Many lichens thrive on various types of gravestones and monuments forming patterns. The most productive are those, which are well-weathered and have been neglected for many years. If you plan a photographic trip to a churchyard choose a day with no rain as many of the species that inhabit rocks are better photographed in dry conditions. This applies to upland mountainous areas as well.
Lichens make great subjects for photography, especially during the winter months when the diversity of subjects is at its lowest. Below are just some of the species from my lichen library which contain around 4,000 images of these bizarre organisms.