During the often bleak months of January and February there is little to see in in our hedgerows. Even the last few remaining berries have been picked clean by hungry birds desperate for nourishment to produce energy and keep them warm.
But all is not so bleak and not everything is dormant and waiting for Spring to burst forth…because if you look closely most trees and shrubs are covered in lichen! Patchworks of crusty layers in grey/green and often orange/rusty deposits cover branches and twigs to create a beautiful colour tint on a cold day.
But with over 2000 different species in Britain, is lichen friend or foe?
Often it can look as if a plant is suffocating under the thick cover of lichen but not at all because lichen is an extraordinary living organism which exists in a rare mutually agreeable balanced relationship between… fungus and algae!!
I’ll try to explain – lichen are cells of algae and live happily in little strands of fungus which are attracted to trees, shrubs and indeed the minerals in stones and rocks – hence the plethora of lichen that grow on gravestones, rocks and walls. The fungus collects moisture and in return the algae (lichen) make food from the sun and air which then feeds the fungus!! So lichen exists on but doesn’t damage it’s host at all.
Lichen provide huge benefits to the environment, vitally, as little mini forests under which lots of creatures live and provide a vital food source for birds particularly in winter. However, lichen grow in exposed areas and rely heavily on moisture and nutrients in the air and thus can act as an indicator of air pollution. The crusty varieties tend to survive in more polluted areas and the common yellow/orange colour is a clear indicator of nitrogen rich air. Often high levels of sulphur dioxide (acid rain) prevents lichen from growing at all, but in coastal areas particularly in the north of Scotland where the air is very clean, rare bushy varieties lichen grow freely.
So next time you are in your garden or out walking stop and marvel at beautiful lichen!
Garden Gate Flowers