Headfort House is among the 100 Most Endangered Sites - along with the Great Wall of China. Sometime in the coming week, a tree, standing in the corner of a romantic semi-walled garden, once part of a vast estate, will briefly flower. This floral display only lasts about three days and then the tree, Davidia involucrate, more commonly known as the Dove or Ghost tree, will revert for the rest of the summer to its more unassuming leafed self. In ways, it's a cautionary metaphor, a reminder of time's swift passage. The tree, of which three were planted in this garden, is part of a subtle, diverse collection of North American and Asian trees - including Ireland's only known Tetracentronaceae or Spur Leaf tree, a single species discovered in China in 1901 - which makes the gardens and parkland of Headfort House, Kells, Co Meath, among the finest in the country. The 100-room mansion, home since 1949 to Headfort School, is an austere, neoclassical building initially conceived as the great house of the neighbouring ancient monastic settlement of Kells or Ceanannus Mór. Headfort's massive granite frontage is plain and as intimidating as it is imposing. The severity of its exterior designed by George Semple is brilliantly countered by the lavish interior created by the Scottish master architect Robert Adam (1728-1792) who met the challenge of designing for a house that had already been built.

