Yews of the world

IT WAS for sombre days in January that I planted Taxus baccata aurea, the prostrate golden yew, just inside the gate. In spring, sure enough, it shines like a gilded starfish, but now, when we could do with a splash of colour, it has tarnished to a slightly brassy shade of green.

But I forgive it. To have any sort of yew on our demesne rings all kinds of cultural bells. I grew up in Sussex, a county of ancient, flint-walled churches, each with a yew or two inside the lych-gate (at one of them, indeed, a tunnel of yew was the lych-gate). At least 500 churchyards in England and Wales, says Richard Mabey in his new Flora Britannica, have yew trees as old as the church itself, if not a good deal older.

In Ireland, too, the association of yews and graveyards is just as striking, if not quite so resonant with ancient, even druidic, associations. Recently, rounding up the final shots for some programmes on herbal medicine and needing a yew tree of some character, it made sense to tour parish graveyards in Co Galway until we found one, at Moycullen. The herbal angle, as it happened, is quite modern: the toxic alkaloid in yew seems effective against ovarian cancer.

The distinctive form of the Moycullen tree, as of most yews planted in Irish graveyards and gardens, goes back some 250 years to two famous seedlings brought down by George Willis from a crag on the Fermanagh side of Cuilcagh in about 1740.

Their branches were stiff and erect - the fastigiate habit handed on, through cuttings, to the "Irish yew" of today. Their branches, in Mabey's image, "all sweep evenly upwards, as if they had been bound into a bundle". One of the seedlings, planted in the Florence Court demesne and still growing there today, became the mother-tree of Taxus hibernica. This ornamental cultivar was planted widely, a dark and sombre spire, like that of the Italian cypress.

To call it simply Taxus hibernica, as many botanists did, would have made it a separate species. "Modern opinion," says Charles Nelson in his Trees of Ireland, "is that this strange tree is a chance mutation that retains certain juvenile characteristics." So it became merely a form: jastigiata.

It has now been cloned by the million (all by cuttings and grafts: the seeds do not pass on the upright genes) in temperate gardens around the world. "No other mutation of tree," says Thomas Pakenham, in his much-praised new book, Meetings with Remarkable Trees, "has achieved this feat of multiplication".

NOT far from Florence Court in Fermanagh, beside a ruined castle on the shores of Lough Erne, is the tangle of sprawling, mossy boughs which has appeared in a number of books as "the great yew of Crom". Even in the 1730s, when the spreading boughs were propped up on pillars, it was referred to as a single tree. Now, Thomas Pakenham has discovered closely-huddled "twins", male and female, planted some time in the 1600s.

Yews can, indeed, be "ancient", but their growth slows down in old age, and after four or five centuries they begin to lose their heartwood. In a giant, hollow tree, there is only the shell of outer rings to count. Richard Mabey quotes some expert speculation that puts three churchyard yews in Wales at more than 4,500 years old - about the age of the "Neolithic" pine trunks excavated from the Mayo bogs.

A tall yew growing in the cloister at Muckross Abbey, Killarney, is sometimes claimed to be more than 1,000 years old. This, says Charles Nelson bluntly, is "ridiculous": the tree stands exactly in the centre of the courtyard and was obviously planted there as an ornament after the building was finished in the 15th century.

Muckross does, however, have the only natural yew woods in Ireland, 25 hectares of it, growing on limestone pavement on the shores of the Killarney lakes. The soil is too shallow and limey for oak, so the yew has formed its own canopy, closing out 90 per cent of the light from the forest floor. Only mosses can flourish in the still, humid air trapped beneath the foliage, and the atmosphere, in Nelson's words, is "gloomy, solemn and quiet as a cathedral".

Yew flourishes on limestone, and, given any chance to spread could be the climax tree of much of the Burren (clothed today where at all, with hazel scrub).

In 1984 Prof W. A. Watts of Trinity College published a study which traced the vegetational history of the Burren since the Ice Age. The pollen record shows yews as a vigorous opportunist, making rapid headway when elm or pine ran into trouble. Its own decline resulted from pressure on the Burren landscape from the first farmers and their livestock.

Yew is more vulnerable than any other tree to browsing of its seedlings and bark by deer, goats and sheep (cattle, on the other hand, can find yew foliage poisonous).

At Killarney, browsing by sika deer has been preventing the yews from reproducing themselves. In the Burren, the problem is mostly feral goats. Without them, wrote Prof Watts: "It is quite conceivable that yew woodland is the potential natural vegetation of much of the Burren.

In his book on the Burren, Charles Nelson describes the extraordinary shapes of the yews of these bare limestone hills: "Some have been plastered by the wind against cliffs, and then on their landward side they are trimmed by goats as neatly as any gardener intent on topiary." He reports with distaste how the animals "rancid stench lingers beside the Mullach Mor trees".

It is difficult to think of the Burren becoming any more extraordinary a landscape than it is today. Yet to picture it under a yew forest, carpeted with mosses, writhing with mahogany-red boughs, wind shrieking through the gloom, is to conjure a film-set for Lord of the Rings.