Organized tree planting initiatives are underway in cities across the world in order to expand tree canopy cover, combat environmental threats, and create more livable places for urban residents. Trees along and near city streets provide a number of services for residents; however, evidence from environmental design and landscape preference research suggests that the perceptual effect of large-statured, mature trees may differ from small-statured, young trees. This dissertation explored these differences in three studies based in communities with active tree planting initiatives. Chapter 2 compares tree preferences from a hypothetical tree planting initiative to preferences for trees in other settings and also identifies the most influential characteristics to choosing a specific type of tree. Chapter 3 relates subjective and objective measures of street-facing trees to resident satisfaction and explores the role of resident satisfaction to potential participation in an urban tree planting initiative. Chapter 4 explores the role of street trees to pedestrian perceptions of safety, based on the presence, maturity, and absence of trees. Implications for theory, research methodology, and practice are considered in the final chapter.