Lichens can survive quite happily in outer space, have been about for millions of years and are sensitive indicators of air pollution. They add amazing colour and texture to our surroundings from the limbs of ancient oaks and high mountain rocks to the mortar in our walls and churchyard gravestones. They provide a home to insects and nesting material for birds. Some lichens smell like fish while others are used to help make perfume! The characteristic orange of Harris Tweed was traditionally produced by a dye extracted from rock dwelling lichens.
Amazing Scottish Diversity
Scotland has an amazing diversity of lichens, with just over 1500 species. Clean air, diverse habitats, relatively cool summers and mild winters all contribute to this diversity and abundance. Scotland is important for lichens on a European and even global scale.
Each type of lichen is a successful partnership between two species, a fungus and an alga (or blue-green alga). The fungus provides a protective home for the alga and in return, the alga produces food for the fungus from sunshine, water and air.
Protecting our lichens
Some species of lichen are common and widespread but others are rare and run the risk of decline or extinction if we do not manage our environment properly. Some of the greatest threats are loss of undisturbed habitats through land-use change, too much or too little woodland grazing, and the swamping out of many important woodland species by the incredibly invasive non-native bush, Rhododendron ponticum. Areas that are of particular importance for lichens are protected by a series of international site designations and national site designations. Some species are protected by law.
Lichens grow very slowly, some less than a millimetre per year, and can take many years to establish in new locations. This is fine for species that live in remote and undisturbed places, but can be a problem for some species that share their habitats with us.
How you can help lichens
- Look after old trees - lichens love them! Keep them free from ivy and other shade and plant similar native trees nearby to provide future habitat for lichens.
- If you own or manage land, find out where the important areas for lichens are and consider them in your management plans (see links on this page).
- Get involved in recording groups to learn about these species and help increase our understanding about where they are found.
- Take care not to let Rhododendron ponticum and other invasive plants spread from your garden into nearby woodland.
- Lichens take a long time to colonise new places. If you need to repair a stone wall, try to re-use the original stone with the lichens intact. If you replace fence posts, leave the old, untreated posts in place as a valuable lichen habitat.
Last updated on Wednesday 29th June 2016 at 15:08 PM. Click here to comment on this page