Although it is well established that viewing nature can help individuals recover from a stressful experience, the dose-response curve describing the relationship between tree cover density and stress recovery is totally unclear. A total of 160 participants engaged in a standard Trier Social Stress Test to induce stress. Participants were then randomly assigned to watch 1 of 10 three-dimensional videos of street scenes that varied in the density of tree cover (from 2% to 62%). Participants completed a Visual Analog Scale questionnaire at three points in the experiment. Analysis revealed a positive, linear association between the density of urban street trees and self-reported stress recovery, adjusted R2 = .05, F(1, 149) = 8.53, p < .01. This relationship holds after controlling for gender, age, and baseline stress levels. A content analysis of participants’ written narratives revealed a similar but even stronger association.
These findings suggest that viewing tree canopy in communities can significantly aid stress recovery and that every tree matters.
Environment and Behavior, published online 25 September 2014View Resource