How Trees Calm Us Down

by Paola Salomon

Roger Ulrich perceived a pattern among patients that were recovering from gallbladder surgery at a hospital in a suburban area of Pennsylvania. The patients whose rooms overlooked a green area with deciduous trees were being discharged a day sooner than those whose rooms were facing a wall. But how can the trees positively affect patients in a hospital by just looking at them? A psychology professor, Mac Berman, led the study with the help of researchers in the United States, Canada, and Australia. The study compares two large data sets from Toronto. “The first measures the distribution of green space, as determined from satellite imagery,” while the second “measures health, as assessed by a detailed survey of ninety-four thousand respondents.” These are results reported by Alex Hutchinson in a 2015 New Yorker piece. They showed that “an additional 10 trees on a given block corresponded to a one-per-cent increase in how healthy nearby residents felt.” The cost of planting new trees is high, yet it was estimated that people would feel seven years younger. Continue reading