ONE by one, the old rushy fields of cut-away bog along the road to Louisburgh are being reclaimed for grazing. Shell-sand stirred in to the shallow peat makes tilth for the greenest of rye-grass meadows.
You have to be a nut about biodiversity to regret this loss of habitat for snipe, dragonfly, bog asphodel, royal fern. half-a-dozen species of rush and sedge. Globally, the "oceanic" blanket bogs. fringing the sea, are down to their last to million hectares but these Mayo lands are just shreds and remnants, long past saving. The more grass we can grow for sheep in degraded corners of the lowlands, the less they will flay the vegetation off the hills: this, at least, is the theory.
Propped up in the middle of the latest raked patch beyond the church is a massive root of bog-deal, spiky and dynamic as a sculpture of Shiva, the god with all the arms. These relics of the old post-glacial pines, excavated everywhere the cut-away-bog is reclaimed, are dragged off into heaps, or make barricades along ditches. When the wind has bleached their old red bones, they are dry enough to saw up and burn.
Nothing dug up around Killeen church can quite match the drama and beauty of the great trunk of bog-deal displayed at the heart of the pyramid at Ceide Fields in north Mayo. That soaring, archetypal form, rich as mahogany, does as much to summon up Neolithic Ireland as any number of stones in the ground.
But we too, have evocative little monuments to the ancient forest of Pin its sylvestris. a lake where the roots intertwine like silver starfish; a beach where a grove of blackened, wave-worn stumps sticks up through the sand from the peat of a long-submerged shoreline.
"Scots pine", it's called today, because the ancient Caledonian pinewoods of Scotland are the tree's last wild refuge in these islands. But Ireland, too, had great woods of P sylvestris right up to medieval times and its disappearance was, as Robert Lloyd Praeger said, "the most notable event in the history of Irish trees". In the plans for new woodlands to mark the Millennium. the oak seems to be the automatic choice. But Scots pine will not only thrive in soils the oak dislikes: it is beautiful and individual (no two trees are ever the same) and its ruddy bark and soft, grey-green foliage are just as much at home in the Irish landscape.
After the Ice Age, it was the first tall canopy tree to arrive in many parts of the island, especially on poorer soils in the west. Starting in the south-west about 9,000 years ago, it made substantial woods on both the granite of Connemara and the limestone of the Burren and took almost another 1,000 years to reach Donegal. Pine woodland was more open even than oak forest and among its birds were the capercaillie big as a turkey - and great spotted wood-peckers, eagles and buzzards.
The tree's extinction in Ireland is still deeply mysterious and the survival of "bog deal" has only confused the popular picture of what happened. Pine stumps found in blanket bog suggest that the bog spread out to envelop the trees and kill them. In fact, most of these trees were growing on the bog in a period of warmer or drier climate.
In the Connemara National Park, for example, pine stumps resting directly on mineral ground are rarely found, whereas many have two metres of peat beneath them. In raised, bogs in Kildare and Offaly, several generations of pines grew on the bog surface for at least five centuries, dated by radiocarbon to between 4,000 and 3,500 years ago. Then as climate swung back, the bogs grew up again to asphyxiate the trees.
The pine became extinct at very different times in different places - about 3,300 years ago in Donegal and Mayo, much later in the south and east. The last Irish woodlands of the native species were on well-drained margins, of raised bogs, like that at Clonsast, near Portarlington, where pine pollen was still sifting down at 300 A.D. or later.
Even today, there are little woods of Scots pines in out-of-the-way places that look as if they just might be descended from native stock. On Clonfinane Bog in Co Tipperary, not far west of Birr, a dozen old trees tower above the hummocks of moss and heather and half-a-dozen others lie where they have fallen. A team of botanists from UCD reconstructed the wood's history from peat and pollen profiles.
They found a gap in the pine pollen record between 240 B.C. and the 17th century (when the new plantings on the big estates - from Scottish seed - were becoming mature). The oldest living pine was dated from the beginning of the wood just over a century ago. The seed, in all likelihood, had blown in from other pines planted near the bog.
TODAY, such invasions continue spontaneously. In their new book, The Bogs of ft& land, John Feehan and Grace O'Donovan show Scots pine crowding in at the margin of Boora Bog in Co Offaly, where Bord na Mona is, helping projects to rehabilitate some 2,000 hectares of cut-away peat. The invading pine is a sign of things to come, suggests John Feehan, as global warming begins to dry the bogs.
For Coillte, Scots pine is high on the list of desirable commercial species. it has, a whole seed orchard devoted to finding the strains which will grow fast and straight in plantations. But, at places like Boora, nature herself is deciding which provenances of seed will re-establish P sylvestris in the wild.
In the Scottish Highlands, projects are under way to restore the ancient Caledonian pine woods by nursing the natural regeneration of seedlings. The Boora example suggests what may be possible within plans for new parkland areas in the vast cut-away boglands of the Midlands.