A logbook with examples of trees that have been equipped with sensors and computer programmes that translate data into social media updates.

Lisle, Illinois, United States


A tweet by @TweetTulipTree comparing the temperatures in November 2022 and 2021. Image source: @TweetTulipTree [screenshot]. Retrieved 21 November 2022, from https://twitter.com/TweetTulipTree

@TweetTulipTree is a tulip tree (Liriodendron tulipifera) that is part of the Tree Observatory Project at Morton Arboretum in Illinois. The social media account tweets about seasonal changes and phenological events in the tree's life cycle and interactions .

Liverpool, United Kingdom


Screenshot of tweets from the @bowiethebirch account, July 2022. Image source: @bowiethebirch Twitter [screenshot]. Retrieved 20 July 2022, from https://twitter.com/bowiethebirch

Inspired by @awitnesstree, @bowiethebirch is an urban birch tree in Liverpool fitted with soil and trunk sensors . Emerging from a partnership between The Mersey Forest and Nadina Galle, Bowie's data is translated into tweets that track his changing state as an urban tree. Read more about Bowie the Birch here.

Petersham, Massachusetts, United States


Image from live feed of the Witness Tree camera, 23 June 2022. Image source: Harvard Forest Witness Tree [live feed image]. Retrieved 23 June 2022, from https://harvardforest.fas.harvard.edu/witness-tree-social-media-project
Screenshot of tweets from the @awitnesstree account, May 2022. Image source: @awitnesstree Twitter [screenshot]. Retrieved 23 June 2022, from https://twitter.com/awitnesstree

The Harvard Forest Witness Tree (@awitnesstree) claims to be the oldest known living organism on social media. In 2018, Tim Rademacher installed sensors on and around a 110-year-old Northern Red Oak (Quercus rubra) in Harvard Forest, Petersham, Massachusetts, after being inspired by Lynda Mapes' book Witness Tree and scientists at TreeWatch.net. Rademacher used the Harvard Forest data archive to contextualise the sensor data with over 55 years of climate data. Technologies include: a dendrometer for measuring real-time tree growth; a sap flow sensor; a phenocam used to detect seasonal changes in leaf fall and colour over time; LiDAR to make 3-D images; and long-term weather data such as soil temperature, relative humidity, and wind speed. A computer programme then translates data from the tree into Twitter and Facebook updates.

On the Internet of Nature podcast with Nadina Galle, Rademacher discussed the scope for expanding A Witness Tree to other trees , not only to collect more environmental data, but also to explore the effectiveness of different environmental communication strategies. In 2022, there will be three additional witness trees in Cambridge, Lincoln, and Boston, Massachusetts. For more information, see the Witness Tree webpage here.

Stockholm, Sweden


Screenshot of three tweets from the @connectedtree account. Image source: @connectedtree Twitter [screenshot]. Retrieved 23 June 2022, from https://twitter.com/connectedtree

One of the first 'Twittering Trees ' is Swedish telecommunications company Ericsson's Connected Tree (@connectedtree). The tree, which first went on show at the 2010 Mobile World Congress in Barcelona, senses changes in the surrounding electromagnetic field and responds by tweeting. It also reacts to movement by playing music, speaking and turning on and off lights.

Connected Tree's account hasn't tweeted since January 2018, and the tree's current Twitter location is 'in Sweden on vacation'.

smart forests radio