The Official Chestnut Tree

Geneva has kept an unbroken written record of a chestnut tree's first spring leaf since 1818, one of the oldest continuous phenology datasets anywhere, third-oldest in the world by the canton's own claim. Every year the sautier, the secretary of Geneva's cantonal parliament, walks to a designated tree on the Promenade de la Treille, checks for the season's first open leaf, and reports the date to the press, a civic tradition treated with the same seriousness as a budget vote. The tree doing the job today is the fourth in the role. The first died young; the second lasted from 1905 to 1929; the third served for 86 years before a root fungus called armillaria killed it from the inside, its final recorded observation logged on 13 March 2015. Its replacement was chosen that September for one quality above all others: standing conveniently opposite Tour Baudet, the tower housing the cantonal government, so the sautier's walk stays short. This is the youngest tree on this list by a wide margin, but the record it now carries is the oldest thing about it, two centuries of Geneva watching the same small square for the first sign spring has actually arrived.