Wonderful world of lichens

WE see them almost everywhere we look, every day, but don’t give them a second glance.

They are part of natural life around us, so much so that we just take them completely for granted.

They thrive on walls, trees, gateposts, roofs, rocks and stones and are often best demonstrated on headstones which have taken the brunt of the elements over many years in graveyards. Anything in the outdoors that appears old has them in abundance. In fact, they make things look old.

We’re talking about lichens — plants without roots that come in a huge variety of colours, often in varied shades of brown, black, green, yellow and grey. Ireland is home to 1,165 recorded species, quite extraordinary for a country of its size, considering that the whole of North America has 3,600 species.

Lichenologists are not the kind of people you’ll meet in every public house or on every street corner.

As they say in Irish, “an rud is anamh is iontach” (what’s rare is wonderful) and that, perhaps, makes the handful of lichenologists we have in Ireland stand out. One such person is Paul Whelan, a graduate of both UCD and TCD, who runs several websites relating to the natural world. Not only that, he has written a 154-page book, Lichens of Ireland, which includes a visual guide to 250 lichens, explains how to look for them and how to collect specimens. Many have technical Latin names, such as Fuscopannaria sampaiana which can be seen on hazel trees in Killarney.

West Cork, Kerry, Connemara and north Mayo offer ideal conditions for lichens because of their hyper-oceanic climate. High humidity and rainfall, mild winters and summers, persistent cloud and frequent fog ensure lichens flourish. The same lichens can be found in parts of North America and Scotland which have a similar climate.

They have been used as medicines, poisons and dyes, or in the manufacture of dolls. Even today, according to Mr Whelan, they are used in perfumes, acting as a fixative to ensure the slow release of scent, which can be moss-like. Some have also been used to cure whooping cough.

Dyes can be abstracted from lichens and used to colour wool. During the 19th century, they became economically valuable and a large cottage industry grew up around their dyes. Lichens also act as a source of nitrogen for many plants and are often the first living forms to inhabit bare rocks.

Birds use them as nesting material and they can be in the food chain of snails, slugs, insects and deer. They can absorb heavy metals from their environment and help both air and water quality.

Mr Whelan says that more than 20% of Ireland’s lichens, many of international importance, can be found in Killarney National Park. Regular soft rain and mists enable them to thrive on limestone rocks and trees in what is generally believed to be the country’s last ancient woodland.

The more exposed landscape of the Burren, in Co Clare, also provides a range of habitat for different lichens on more hostile open limestone. Skellig Michael, off the south Kerry coast, has 128 species of maritime lichens, some extremely rare.

Now to an entirely different plant — ragwort (buachallan bui) which can poison animals and which can be seen in yellow profusion in fields and on roadsides.

Kerry councillor Michael Gleeson has called for a comprehensive programme to eradicate ragwort, saying its continued proliferation, in breach of the Noxious Weeds Act, is a health hazard to animals. In 2008, he said, the National Roads Authority allocated a sum of money to Kerry County Council, in addition to the normal road maintenance grant, for the control of ragwort. However, this allocation was suspended indefinitely in 2009 and he called for its restoration.

Mr Gleeson said it was shameful that local authorities all over the country disregarded the law by allowing ragwort to thrive unchecked along roadsides. “It is even more of a disgrace that the National Roads Authority allows the weed to proliferate along the dual carriageways, especially on the one from Naas to Dublin. “To have the state directly itself, and indirectly through local authorities, blatantly ignoring the law is shameful and grossly hypocritical.”

* Lichens of Ireland — an illustrated introduction by Paul Whelan; The Collins Press, €19.99.