Amid the future-facing early 21st century enthusiasm for urban greening initiatives, this paper takes a more-than-human historical view, asking what we can learn from this approach to past urban greening efforts. Archived local government files from the City of Nedlands and City of Fremantle in the Perth metropolitan area document a large-scale experiment in urban greening from the 1920s to 1970s. They reveal both the historically contingent reasons for the age and species composition of the current urban forest in those areas, and the diversity of human residents’ emotional responses to ‘their’ street trees – from love to loathing, and collaboration to conflict. Tracing the lively growth of the urban forest in these two areas over time also suggests a detectable shift in relations as urban forests mature: the files are initially dominated by human residents’ requests for trees and offers of care, but over time there are increasing requests for maintenance or even removal, as older, larger trees are perceived as as hazards for traffic and cover for loiterers, or as messy pests that block light and views. The maintenance of the forest through pruning then becomes a source of lively debate. A more-than-human history of these urban forests stories them as co-constituted through local government policy, human residents’ specific attitudes, broader cultural and technological factors, and the life cycle and particular features of the urban forests themselves.