What is the oldest tree in Brzoza?
Brzoza has three protected trees and no documented age for any of them: the Gniewko Oak, measured at 375 to 415 centimetres round, and two limes at 380 and 320 centimetres, all made nature monuments together in 2014. The girths suggest centuries-old growth, but nobody has dated them.
All three trees stand within about fifteen metres of each other on one plot in section 178n of the Rudak forestry district, part of the Gniewkowo state forest district roughly ten kilometres north of Toruń. The Wielka Nieszawka municipal council made them nature monuments together in a single resolution, XLIII/207/2014, passed 7 October 2014 and gazetted later that month. The oak, named Dąb Gniewko, is given a girth of 375 centimetres by the forest district's own conservation page and 415 centimetres by Wikidata, plus a height of 26 metres in the second source; the two figures agree on species, place and designation date, so read the trunk as somewhere between them. The two limes, named Lipa Bolka and Lipa Brata Alberta after Brother Albert Chmielowski, measure 380 and 320 centimetres and rest on the forest district's page alone, which is why both are flagged. Nobody has dated any of the three. The setting is working state forest rather than a park, open to walk on under Poland's general right of access, with no gate and no ticket.
One of Brzoza's trees also appears in The Autumn Harvest, a themed collection spanning several cities.