The Kossaka Square Ash

Plac Kossaka today is better known for parked cars and a kebab stand than for its trees, which is what makes the ash at number 4 easy to miss. It measures 321 centimetres around, entered onto Krakow's natural monument register in 1997, and stands a few streets from the city's other protected ash on ul. Straszewskiego, itself 375 centimetres and estimated at 150 to 220 years old by the same method. Scaling this tree's girth against that already-published estimate, using the same borrowed growth factor (European ash has none of its own published, so the figure comes from green ash, its closest documented relative), puts the Kossaka tree at roughly 130 to 190 years. Narrower trunk, younger tree, same square kilometre of the city. European ash is one of the commonest species in Poland, which is exactly why a trunk this thick stands out. The species has also had a hard three decades: a fungal dieback moving west since the 1990s has thinned ash populations across the continent, killing young and old trees indiscriminately. A veteran ash surviving that, on a square used mostly for parking, is a small piece of luck rather than a guarantee. Free and open to the street at any hour.