Q: What links harbour buoys, the seats of Windsor chairs, wheel hubs, water pipes, the bottom boards of a lugger, coffins? A: They are all best made of common elm, Ulmus procera, because they all exploit elm’s resistance to splitting and tolerance of saturation with water. Thus if the key structure of a buoy is a ring of elm, it can ride the knocks without splintering and it will remain immune to fungal attack as long as it is not left to dry out at low tide. Or again, the oldest water pipes in the world are made of elm. …