Branching out new routes to valuing urban treescapes

A climate emergency has been declared by 74% of UK local authorities. As they respond to this via increased tree planting targets for carbon sequestration, it is imperative that they also realise the multiple public benefits - health and wellbeing, green infrastructure, social amenity, the green economy - that treescapes can provide. Local authorities need a vision of future societal needs and the forms of future treescapes that might meet them; we will deliver the evidence and decision making processes to realise such a vision.
Most studies on the biophysical and amenity aspects of urban treescapes neglect wider social and cultural values that cannot easily be quantified. Consequently, the symbolic, heritage, spiritual and social and cultural (S&C) values of treescapes are not meaningfully accounted for. This problem is becoming increasingly acute, as protests arise around individual trees (Sheffield street trees) or woods (proposed sale of the public forest estate), exacerbated by pressure from business and housing development. 'Branching Out' will evaluate the S&C values of urban trees across three cities, and develop new ways of mapping, predicting and communicating those values to support robust, evidence-based decision making and management.
The three selected focus cities purposefully have different planning histories, supporting subsequent widespread adoption of our novel approach. York (historical) and Cardiff (post-industrial) are county towns, while Milton Keynes is a post-1960s new town. Each city has particular, yet not uncommon, challenges relating to their treescapes, has declared a climate emergency, and expects trees to play a role in mitigation and adaptation. Our central tenet comprises three broad approaches: 1) co-production, using deliberative methods with citizens and stakeholders, to develop a holistic value framework; 2) storytelling, creating narrative accounts of meaning and value of the past, present and future; 3) mapping, to link biophysical features and S&C values. Our approach will map both values that are generalisable and those that are particular and highly situated.
Our mapping approaches encompass the past, present and future, using historical sources to map the impact of past values on current treescape form and function. We will use our established tree citizen science platform, Treezilla, to collect biophysical data from new Urban Tree Observatories. Remote sensing will characterise tree condition and canopy properties, and scale the biophysical data across the focal cities. This project will address local authorities' need for high-resolution mapping of tree characteristics, resulting in Europe's largest, most robust urban tree dataset, accompanied by descriptors of S&C value that can be used to recreate such datasets across other urban areas using freely available satellite data. The tools we co-create will provide local authorities with useable evidence for decision making to predict the impacts of developments or changes on S&C value, and enable them to calculate more accurately the impacts of changes on ecosystem services. Such multidimensional mapping can reveal inequalities in current and future provision of benefits as treescapes change through time, providing a better understanding of how and where those inequalities can be addressed.
A series of design workshops will experiment with ways of mapping S&C values in relation to the remote-sensed biophysical characteristics of our urban treescapes, producing techniques and tools for sensing and mapping values. Using these tools as provocations, we will speculate on possible futures for our urban treescapes, built around an appreciation and understanding of S&C values. Through these methods this project will embed S&C values in planning and decision-making for urban trees at local and national scales, thereby meeting society's and planning needs now and in the future.