The Oak of Libocka Gate, Hvezda

Prague's own conservation register cannot decide what this tree is. It has been listed since 2002 as a pedunculate oak, Quercus robur, but a 2015 update to the same register filed its data under Quercus petraea, the sessile oak, and the leaf photographs the register itself attaches are petiolate: stalked at the base, the sessile oak's diagnostic feature, not the pedunculate's near-stalkless leaf. Oak makes up 57 percent of the trees in the Hvezda reserve, nearly all of it pedunculate, and if the register's own photographs are read correctly, this crooked, gnarled specimen is the reserve's only individually registered sessile oak among them. Whichever species it is, it has grown steadily since a formal survey first measured it in 2001, when its trunk read 345 centimetres round. By 2009 that had reached 352, and by 2013, 356, the figure the register still carries today. Assessors call its health excellent apart from a few dry branches and note it is actively maintained, which for an eighteen-metre tree with a sixteen-metre crown standing beside the reserve's busiest path is not surprising. Nobody has cored it, so 175 years is an estimate rather than a count, and the register put it near 165 in 2016. It has been protected since October 2002 and stands right of the main path from the Libocka gate toward the star-shaped Hvezda summer palace, past a stand of registered horse chestnuts and just before the reserve's playground.