The Plane of Viale Po

The thickest trunk on this page belongs to a street tree rather than to anything growing in a park or a palace garden. This London plane on Viale Po measures 5.40 metres round, on a tree 20 metres tall, and the city has nominated it, along with a short list of other exceptional specimens across Ferrara, for protection under the Emilia-Romagna region's safeguarding measures for flora of particular merit. London planes were planted along avenues across European cities from the 18th century onward for the same practical reasons that still apply on Viale Po: fast growth, tolerance of compacted soil and pollution, and a canopy wide enough to shade a whole street. What sets this one apart from the species doing the same job on a thousand other avenues is simply scale, a girth most street planes never come close to reaching before they are pruned back or replaced. No individual planting date survives for it, which is ordinary for a street tree rather than a garden specimen with its own record. The register measures it; nobody has dated it.