Ferraraで最も古い樹木はどれですか。
Ferrara's oldest individually dated trees are the gray poplar in the garden of Palazzo dei Diamanti and the bagolaro (Mediterranean hackberry) of Parco Massari, both put at about 150 years by the city's own museum records. The Biblioteca Ariostea's ginkgo is first documented from 1890, which sets a firm minimum age without confirming exactly how much older it might be, since it began life as part of the university's old botanical garden before that record starts.
Italy's national monumental tree register gives girth, height and location for every entry here but no age field, so the dates on this page come from Ferrara's own civic museum, MuseoFerrara, which has researched several of the city's protected trees individually and published a page for each. The gray poplar at Palazzo dei Diamanti and the bagolaro at Parco Massari both carry a museum estimate of about 150 years, tied to the buildings and gardens they stand in rather than to a planting record. The Ariostea ginkgo is different: its first written record dates to 1890, when it already stood in the University of Ferrara's old botanical garden, once housed in the same Palazzo Paradiso courtyard the library now occupies, so its documented age is at least that of the record and very possibly more, since nothing says how old it already was in 1890. The second ginkgo, in Parco Massari, and the plane on Viale Po carry no individual age estimate at all, only their register measurements, so none is claimed for them here rather than guessed at.