Tread carefully this summer: our plants are in peril

ANOTHER LIFE:THE WESTERN HILLS had to wait for rain before blackened slopes, from Donegal to Connemara to Kerry, began to turn green again after an unprecedented, reckless scorching of the earth. Coillte alone counted 350 fires this spring, costing many millions in burned conifer plantations. The cost to nature was only to be guessed at in calcined hares, lizards and frogs, and charred or starved nestlings of hen harriers, stonechats, wrens, thrushes, pipits, larks.

The fires went on for many weeks past the legal cut-off date of March 1st. How many were purposeful, how many the madnesss of young vandals after the pub, we shall never know. Environmental groups have blamed a change in the single-payments scheme that ties payment to farmers to “utilisable areas” of land. Scrubby hectares dotted with gorse don’t qualify, and fire may have seemed the way to start reclaiming them.

There are laws that limit “traditional” burning, but gardaí find them unenforceable (“Me, sergeant? Sure, I was up there trying to put it out!”) Fire brigades, never so hard pressed as this year, worry only about harm to people and property.

Given the scenarios of global warming, the future of the peaty western uplands is gloomy enough, as bog vegetation changes and high slopes of blanket peat dry out, crack open and slip off the rock. In my own landscape, a great landslide on the mountain across Killary Harbour from Leenane refuses to green over. In the heart of Connacht’s sheep country, the scar evokes the last wave of human folly – decades of subsidised overgrazing of fragile peatland slopes.

Remedial farm plans have taken some effect, but most of the heather has vanished for good, and with it many of the botanically famous rarities of Ireland's mountain plant life. Some typical damage was spelled out this spring in the UK science journal Field Bryology, under the heartfelt heading: "The tragedy of the Twelve Bens of Connemara: is there a future for Adelanthus lindenbergianus?" As little plants most people don't know exist, the liverworts tend to get stuck with only scientific names, "Lindenberg's featherwort" is at least a little easier to say, but what is so special about it? Like the mosses, liverworts were some of the earliest land plants of the planet, branching off the vegetable evolutionary tree below the ferns and then the plants with flowers. Many of them seek out out the shade of heather and other dwarf shrubs among the rocky scree of rain-soaked oceanic mountains. There they form a mat, often a striking mix of colours, that helps weld the stones together.

Lindenberg’s featherwort is one of the larger liverworts, raising tufts of tiny overlapping leaves up to 10cm high. It was first described by a German botanist in South Africa and grows also in tropical Africa and south and north America. But in Europe it has been found only on mountains in Donegal, Mayo, Galway and Kerry and on the western Scottish island of Islay. How it got to Europe (probably wind-borne spores) has been a mystery fascinating modern botanists, among them David Long of Edinburgh’s Royal Botanic Gardens. Family links to Cleggan, in Connemara, have brought him to the Twelve Bens since the 1980s.

When the featherwort was first found there, in 1961, it grew abundantly with other liverworts on steep slopes some 550m high and covered with ankle-deep heather. Dr Long, too, found it easily in 1984. In 1994, at the peak of overgrazing, a botany group found "devastation – a few broken fragments of heather [and] small and sorry pieces of A. lindenbergianus." Since then Dr Long has searched the Bens repeatedly without success, but in 2007 he found and photographed a small clump in steep, rocky terrain: "This could be," he writes, "literally the last survivor in the Bens."

Another UK bryophyte specialist, David Holyoak, believes it is already too late for the liverwort heath to recover, “unless destocking were to be followed by reintroductions”. Dr Holyoak has been working with Neil Lockhart, the bryophyte specialist at the National Parks and Wildlife Service, on a Red Data list of Ireland’s endangered species.

When the overgrazing was at last acknowledged, all the western mountain commonages were mapped for damage and the numbers of sheep they could bear (unfortunately, as David Long observes, Connemara’s sheep like to graze on the highest slopes). Conservation now depends on the farm plan scheme that has followed the Rural Environment Protection Scheme – this, of course, as long as the money holds up. In some visionary future, as botanists would wish, Connemara National Park may need to cover the Twelve Bens as a whole. In the meantime this summer’s high walkers may care to watch where they’re treading.

Eye on Nature

I saw a mallard hen with her seven chicks ­ a few days old — on the canal under Wolfe Tone Bridge in Galway. Six of the chicks had the same brown colouring as the mother, but one was bright yellow.

Liam O’Donovan, Galway

It is not unusual for a yellow chick to appear in a mallard clutch as the result of a recessive gene lurking in the genetic pool.

My marigolds were attacked by slugs, so I put down slug pellets and next day was glad to see the tell-tale silver trails indicating that the blue pellets had done their job. However, I noticed that all the pellets had disappeared. Could birds have eaten them?

Ted Greene, Drogheda, Co Louth

It is safer to net the area in which slug pellets are spread, to prevent birds taking the bait or eating the poisoned slugs.

On the last weekend in June, on the Aran island of Inis Mór, I awoke at about 5am and listened to a cuckoo outside my bedroom window for about 10 minutes.

Martin Coffey, Tallaght, Dublin

It was very late for a cuckoo to be calling, as the breeding season was over and the cuckoos leave in July.

Michael Viney welcomes observations at Thallabawn, Carrowniskey PO, Westport, Co Mayo, and viney@anu.ie. Please include a postal address.