The bristlecone pine trees of America are the oldest living things in the world, some 5,000 years old, but Britain is home to some respectably old trees as well. One of the oldest is the yew in Llangernyw churchyard, whose great age was only identified in the late 1990s and promptly put at risk by the church authorities' desire to make their church yard look neat and tidy by hiding untidy things behind hedges and - er - in trees.