Lichens of our ancient Welsh woodlands

With over 70 National Nature Reserves in Wales, we are all only a few miles away from a special place to discover nature.

Our colleagues working to look after the National Nature Reserves (NNR) have got together to write a blog, bringing you the latest news and goings on from a different site each month.

This month's blog is from Coedydd Aber Reserve Manager Huw Green...

Just before Christmas whilst out in the woodland at Coedydd Aber National Nature Reserve, (located midway between Bangor and Llanfairfechan) I had an early Christmas present when I discovered a new species not previously recorded for the site.

The new find was a lichen by the name of Lobaria virens, a species which is considered endangered in Wales and is one that Britain has an international responsibility to conserve (Woods and Coppins (2003)). 

Lobaria virens belongs to a community of lichen species known as the Lobarion, which are Ancient Woodland indicators associated with the Atlantic woodlands of the western coast of Britain. These woodlands receive so much rain some of them are considered temperate rainforests, containing trees and rocks adorned with the vibrant colours and interesting structures of a diverse array of lichen species.

Before I ramble on about lichens I should explain what they are.

Lichens are an association between two completely different organisms, a fungus and an alga or cyanobacteria. The fungus provides the structure (a safe home if you like) for the alga or cyano bacteria to live in. And the algae or cyanobacteria produce the food through photosynthesis for both to benefit from.

Why are our Welsh rainforests such good homes for lichens?Loberia pulmonaria on Oak tree in Coedydd Aber

Our mild winters and high levels of rainfall throughout the year, created by the influence of the Gulf Stream, create the perfect conditions for a diverse ecosystem within which woodland lichens can thrive. Many of the species are largely confined to these humid woodland habitats and is the reason why many species are rare or threatened.

Our landscape has undergone many changes in the past with large areas of our native woodlands having been clear felled over time. The presence of these special groups of lichens is an indication that pockets of woodlands have avoided being cleared completely, and have retained these beautiful and very special organisms.

Our temperate rainforests have a magical feel, with trees covered in lichens and mosses giving you the feeling you are walking through a truly ancient woodland.

Managing a woodland for Lichens

The lichen assemblage at Coedydd Aber is so important that it strongly influences the way we manage the woodland.

A great deal of care and planning is needed to get the grazing pressure and patterns correct to create the ideal conditions for the lichens and woodland at the same time. 

We work closely with the staff at the Bangor University Henfaes Research Centre, who graze the woodland at Coedydd Aber NNR with a flock of welsh mountain sheep. We have also recently been working with the organisation Plantlife, who have been extremely helpful in helping determine the current condition of the lichen populations at Coedydd Aber.

Lichens are notoriously difficult to identify taking many years to become a competent field Lichenologist, able to identify the numerous different species.

Dave Lamacraft (IPA Lower Plants Champion (England and Wales) has recently been carrying out survey work to determine how the lichens at Coedydd Aber are doing. Thankfully its good news with many of the scarcer species doing well and colonising new areas since the site was last surveyed.

Woodland expansion

The native woodland in Coedydd Aber is expanding!Coedydd Aber Woodland

The nearby conifer plantation which shares a boundary fence with the nature reserve is currently being clear felled.

Due to difficulties of extracting timber from the site, areas being clear felled will not be re planted with conifer species but will be restored to native broadleaf woodland.

A 30 Hectare area in the middle of the plantation is already on its way with established 10 year old native trees growing strong. With this, the native woodland at Aber could potentially be expanded by more than 1 square kilometre!

This would be a huge gain for the wildlife of the area and a massive boost to biodiversity.

So the next time you visit Coedydd Aber (or other native woodlands in wales), take a minute to notice the lichens that cover the trees, with their many different forms and colours. Also take a glance up at the plantation and imagine an established native woodland clothing the valley side.

Visiting Coedydd AberTemperate Rainforest coedydd Aber

Visitors are welcome, and one of the main attractions is the spectacular waterfall. The path goes from the entrance at Bont Newydd to the foot of the Rhaeadr Fawr waterfall, and there are a few picnic sites along the way

There are also many features of historic and archaeological interest, including an Iron Age hill fort and the remains of several round houses.

More information about visiting Coedydd Aber can be found on our website.