Do Trees Really Make a Difference to Our Perceptions of Streets? An Immersive Virtual Environment E-Participation Streetscape Study

Urban streets, constituting the majority of public space, are often designed to prioritise vehicular movement over the pedestrian experience, leading to environments that can feel unsafe and unwelcoming. While street trees are advocated for their multi-faceted benefits, empirical evidence quantifying their specific impact on pedestrian perceptions of traffic safety and place, distinct from other interventions, remains limited. This study utilised an immersive virtual environment (IVE) e-participation method to isolate and evaluate the impact of streetscape designs on pedestrian perception. We asked: How do street trees and other interventions influence emotional responses and perceptions of traffic safety and comfort? Our findings demonstrate that streetscape modifications significantly alter pedestrian affect. Crucially, a ground vegetation buffer reduced tense emotions by 69% (Exp(B) = 0.302), performing comparably to traffic speed reduction (−71%) and cycle lanes (−81%). The results provide robust, quantitative evidence that integrating vegetation, particularly tree and low planting buffers, is a highly effective strategy for mitigating negative emotional responses and enhancing the liveability of urban streetscapes. This study offers planners and designers validated strategies for creating streets that are not only functional but also psychologically supportive.