Lichens

Lichens are not one organism, but are a symbiotic association between a fungus and an algae and/or cyanobacteria. They appear as one organism, as they are so interwoven. Lichens are a fungus and one or more partners called photobionts. The fungi need an external source of food and so build a structure for the photobionts, who produce simple sugars via photosynthesis. This really amazed me when I found this out. They really have got it all worked out. I had no idea. Everyday I am finding out some new interesting fact about the world around me. Forest bathing really is expanding my mind.

The CountrysideInfo website explains how there are over 1,700 species of lichen in Britain, and over 18,000 worldwide. This to me is a staggering amount, as I have only seen a few varieties. This is probably because I have only just started forest bathing, though, and have not really been taking much notice of the outside world as I dashed on by. The website also states how some found are thought to be 9,000 years old!

Lichen can be used as an indicator for air pollution, as different varieties tolerate pollution better than others. If there is a lot of sulphur dioxide in the air then there will be no lichen, but there may be green algae present. Leafy lichen prefers clean air. You could check out the lichen growth in your area to see how polluted it is.

Countryside Info lichen information link