Scientific and participatory observatory of urban tree health – OSCAR

Trees play an essential role in the functioning of urban socio-ecosystems, providing vital ecosystem services for city dwellers. The diversity, size and distribution of trees in urban spaces reflect the socio-cultural dynamics of cities. Urban trees are vulnerable to environmental stresses and, as such, are sentinels of global change (heat, drought, soil artificialisation, erosion of biodiversity, introduction of species) as much as they represent a management lever for adapting cities to climate change. Understanding the factors that make urban trees vulnerable to biotic and abiotic stresses is essential if we are to manage the urban forest and sustainably drive the ecosystem services provided by trees to city dwellers. As the majority of urban trees are privately owned, urban forest management initiatives need to be a joint effort between municipal services and private individuals. This implies that all stakeholders share the same knowledge of the matter, the different management options and their consequences. It is therefore essential that scientific knowledge about turban tree health is accessible, understood and shared between the great diversity of stakeholders and citizen. OSCAR - the Scientific and Citizen Observatory of Urban Trees Hetalth - has this threefold ambition: (1) to co-construct scientific knowledge through the sponsorship of sentinel trees, (2) to encourage the dissemination of this knowledge in various forms so that (3) it can be appropriated by individuals and managers of green spaces and urban forests.