The European Hop-hornbeam of Villa Serra

This is the only tree on this list whose age somebody actually wrote down. Italy's national monumental tree register has no age column, anywhere, for any entry, which is why nearly every date on this page is reasoned back from a trunk measurement. Liguria runs its own regional register and that one does carry the field, and for this hop-hornbeam it reads approximately 160 to 170 years. It is a modest tree to be the best documented of the set. Ostrya carpinifolia is a small, unshowy relative of the birches that rarely makes a specimen tree at all, and park competition has drawn this one up to somewhere between 22 and 32 metres, depending on which register you believe. The two agree on the 256 centimetre trunk and disagree on the height, so both figures stand here rather than one. In late summer it makes the fruit that named it, hanging clusters of papery pale bladders that look like hops on a vine, each holding a single seed. Ligurian woodsmen cut this species for tool handles, cartwheel spokes and vine stakes, because the wood is heavy, hard and will not split. It stands with three larger trees inside sixty metres at Villa Serra, in Comago, in the comune of Sant'Olcese, up the Polcevera valley from the city.