What is the oldest tree in Geneva?

Geneva's tree age claims split into two honest categories: a handful backed by documentary evidence, and a majority inferred from girth and planting-era estate records. The plane trees are the rare first case, cross-checked against the canton's own 1728 cadastral survey rather than estimated from trunk measurements, which is why this entry names them ahead of Parc Beaulieu's cedars even though both plantings sit in the same rough era. The Beaulieu cedars have the better-known story, seeds gifted in 1735 from the same Bernard de Jussieu shipment that produced Paris's own celebrated Cedar of Jussieu, but their 1735 date describes when saplings were planted, not when the seed itself was gathered, so a small margin of uncertainty sits underneath the widely repeated figure. Parc de la Grange's cedar, grown from Beaulieu seed a generation later, and Parc Barton's sequoia grove, planted from 1858, are both younger by a wide enough margin that the ranking among Geneva's oldest three rests on the plane trees and the cedars, not on any of the newer estate plantings.