The Lorentz Monument Oak

Hendrik Lorentz got his monument in 1931. The oak beside it had been standing for well over a century by then. Arnhem's national register of monumental trees puts this pedunculate oak's planting somewhere between 1750 and 1800, which makes it around 250 years old and, by the register's own reckoning, possibly one of the oldest trees in Park Sonsbeek. What the register admires is its shape. It calls this one of the most beautifully formed and image-defining trees in the park, and explains why in a single line: the oak has had open room around it from the start, so the crown went sideways instead of straining upward through neighbours for light. Storms have taken pieces out of it over the years without leaving lasting damage. The monument it now shares a lawn with is L.O. Wenckebach's 1931 memorial to Hendrik Lorentz, the Arnhem-born physicist, and it makes this oak the easiest tree in the park to give directions to. The ground under both was private for most of the tree's life. The Van Heeckeren family bought the estate in 1821 and had J.D. Zocher jr lay it out in the English landscape style; Arnhem bought the whole thing in 1899 and has kept it open and free since. Only the register has written this tree down, and it records no girth. If you have measured it, tell us.