Keys to better planning and integrating urban tree planting initiatives

Urban tree planting initiatives have been blooming worldwide to help tackle climate change and nurture healthy living environments for people and biodiversity. Many initiatives are characterized by ambitious targets based on the number of trees planted but are not defined by clear objectives, which hampers the success of these initiatives in achieving the desired benefits. Growing an urban forest is a long-term endeavour that requires sustained commitment and support by urban communities to fully realize the provision and even distribution of multiple benefits. In this perspective article, we discuss the characteristics of tree planting initiatives and argue they should be better connected to urban forest management objectives. We propose seven principles that can help improve the success of tree planting initiatives by ensuring that the right types of trees are planted where they are needed most and where they will have the greatest impact. These principles include: (1) connecting initiatives with long-term management, including defining desired benefits, objectives, targets, and indicators; (2) facilitating community engagement on tree planting and maintenance; (3) focusing on tree canopy cover targets rather than on the number of trees planted; (4) focusing on post-planting care and encouraging retention of existing trees; (5) monitoring tree losses and gains to determine whether the specified targets are being met; (6) increasing species diversity, through careful species selection, as well as age and size diversity to enhance urban forest resilience; and (7) addressing the inequitable distribution of tree canopy, specifically where low tree cover overlaps with socioeconomic needs.