All the trees of The Hague are registered in a computer programme: their name, age, diameter of the trunk, etc. Recently these dates have become available, free of charge, via an app for Iphone and Ipad.
This news-item and many more one can read on the site: Den Haag – Nieuwsbrief “Bomen voor de Toekomst”. This newsletter comes out four times a year, at the changing of the season. Subscription is free.
13 October 2013, FH