In this project the human participants wanted the audience to meet us, trees, as you meet a work of art. Arnhem has beautiful parks, famous for beautiful old trees like me and my colleagues who also participated in this project: the Solitary Oak in the Moerasweide, the Horse Chestnut near the Witte Villa, the European Oak on the way to the Belvedere Tower, one of the Red Beeches near Zijpendaal Castle and a Douglas Fir in Schaarsbergen-Zuid.

Using sensors installed in our trunks and branches, Arnhem Trees Tell made visible what otherwise remains hidden from the human eye: the movements of our trunks, our CO2 and water supply, the temperature in the air and at our roots, and the amount of sunlight that helps us in our photosynthesis.

You find the full documentation here: https://wiki.bomenvertellen.net/index.php?title=Arnhemse_Bomen_Vertellen

QR code in bench

Near each of us trees, a wooden bench was placed with a QR code on it. These benches were made of wood from trees of Arnhem. By scanning the QR code, the visitor was guided to a web page where story fragments, an artistic soundscape and digital images provided insight into the life and history of the tree. What one got to see and hear depended on the location and the data sent by the sensors.

Walks

For regular visitors to the parks, it was possible to meet one or more trees on a daily basis, to get to know us and make new, lifelong friendships. Visitors who didn’t have a smartphone or preferred not to walk could visit the portraits of the six trees using the touchscreen in the visitor centre at Molenplaats Sonsbeek. There they also found a small exhibition with artistic visualizations based on the data sent by the sensors.

Collaborators

The humans participating in this project were An Mertens (concept, coordination, tree clerk), Gijs de Heij & Doriane Timmermans (code, design & visualizations - Open Source Publishing), Christina Clar (sound), Bram Goots (photos), Loïc Lachaize (mastering), Floris van Hintum (benches/stand), Patrick Lennon & Karin Ulmer (proofreading).

The trees participating in this project: Gatekeeper Chestnut, Red Beech Zijpendaal, Horse Chestnut Witte Villa, Solitary Oak Sonsbeek, European Oak Ronde Weide Sonsbeek, Douglas Fir Schaarsbergen-Zuid

The algorithms collaborating on this project: Decentlab sap flow sensor, sunlight sensor, CO2 & temperature sensor; EMS Brno tape drometers, Sensoterra soil moisture and temperature sensors, Milesight CO2 sensors, SenseCap CO2 sensor; django, leaflet, sqlite, D3 javascript module, Python programming language, html, css.

We thank for their advice: dr Ute Sass-Klaassen (Hogeschool Van Hall Larenstein), Hélène van Ginderachter, ir Erik Mertens, Joost Verhagen (Cobra-Groen in zicht), Judith Van Ginneken, Marleen Verschueren, Erik De Wilde.

We thank for sharing knowledge, experiences, and stories: park guide Eddy van Heeckeren, forest expert Simon Klingen, ecologist Hans Van den Bos, artist Boudewijn Corstiaensen, park administrators Jan Floor, Rob Borst, senior administrative adviser on green spaces Marcel Wenker, nature guide and biologist Pim van Oers, park guide Gerard Herbers, artist Albert van der Weide, forester Nina Kreisler, author Jibbe Willems, city ecologist Ineke Wesseling, artist Bartaku Vandeput (Baroa belaobara).

The sensors and benches were installed with the very kind help of the tree care staff from the municipality of Arnhem. Thank you for your help and patience: Ruud Krabbenborg, Arthur Wanders, Tony Berendsen, Lucas Willen Beemster, Dave Bobeldijk, Tim van Leeuwen, Jan Floor.

This project was made possible thanks to the support of Marko Van der Wel (Nature, Environment, Care, Local Food, Water), park manager Rob Borst and senior management advisor green living environment Marcel Wenker. Communication was ensured by Sanne Blok, Hanneke Busscher and William Hulstein; production by Karlijn Michielsen. Thank you!

And finally, we are grateful for the cooperation and support of the municipality of Arnhem and Natuurcentrum Arnhem.