While the benefits of urban forests (UFs) are well-researched, less is known about how to steer collective action for conserving and strengthening this resource, and particularly the role of local government. We address this knowledge gap through a study of urban forest governance in Scotland, United Kingdom. Applying a mixed-methods approach including semi-structured interviews, document analysis and surveys, covering 26 out of the total of 32 Scottish local authorities (LAs), we show that UF management by Scottish LAs is largely reactive. This can be explained by limited funding and knowledge of the resource, poor knowledge of the scale and state of the UF, fragmented management structures, and the tendency to perceive trees as a liability as opposed to an asset. However, some LAs successfully resist this trend through city officials acting as frontrunners within their organisations. They do so by championing activities such as investing in tools for socioeconomic valuation of the UF, pursuing grant funding, breaking down silos through organisational reorganisation, preparing city-level trees and woodland strategies, cross-sectoral partnership working and community engagement. Fundamental change, however, relies on the combination of these activities and therefore requires a whole-organisation commitment to UF sustainability across different domains relevant to predicting UF outcomes.