Lichen

Lichens are extraordinary but often overlooked group of plants. They are of growing importance to the environmentalist as they are a good indicator of air pollution. This is useful, as if they are seen to be making a come back in an area it is likely that the air quality is improving.

Lichens are flowerless plants that have an unusual physiology. Lichen are a consequence of a combination of a green algae and a fungus. This symbiotic relationship is beneficial to both organisms. The algae provide oxygen and carbohydrates to the fungus. The fungus brings into the relationship; water, mineral salts and through its hyphea a method of attachment.

Lichens are hardy organisms (except with Air Pollution). In tough environments they are often the first to settle. They have the ability to thrive on bare rock even under extreme climatic conditions. Under such conditions they are often the prominent life forms as in these instances benefit from minimal competition from green plants.

Lichens themselves are an important stage in the colonising of other plants. In harsh regions such as bare rock faces, they are the only life form that can exist. When the lichen die they disintegrate, their remains falling into crevices and form the base of a primitive soil, providing a foothold for other plants.

Examples of Lichen

Uses

Man has used lichens for centuries as food and medicine. They were once used to provide dyes for woollen goods. However many of their dyeing uses have been superseded by synthetic dyes

Locating

In Cornish towns they can be seen everywhere, on roofs, walls and trees. These beautiful compact plants come in a variety of colours. However they are relatively small and merge in well to their background, so one might walk pass these plants many times and still not notice them. The best places to find lichens include, on trees, the supralittoral fringe of rocky beaches and in the tranquil settings of old grave yards.

Lichens in The Supralittoral Fringe