City Trees is a premier publication focused on urban + community forestry. In each issue, you’ll learn how to best manage the trees in your community and more!
Issue link: https://read.dmtmag.com/i/1498043
Urban forests and the human immune system Greenspace can improve human health in a range of ways. For example, by improving air quality, reducing stress, and increasing physical activity. However, recent research suggests that greenspace may also improve health by improving immune function. This is consis- tent with the biodiversity hypothesis, which posits that global loss of biodiversity is contributing to increased incidence of immune diseases especially in high-income countries (Haahtela et al. 2013). Strictly speaking, trees and plants do not directly influence human immune function. Rather, it is the microbes that live on plant leaves that help our immune systems mature. While the link between plants and human immune func- tion is still being explored, we know that exposure to other sources of microbes–attending day care or having older siblings, for example–makes children less sus- ceptible to immune diseases (Strachan 1989). To date, research has shown that children that are exposed to greater plant diversity are at lower risk of developing immune diseases including asthma and childhood leu- kemia (Donovan et al. 2018; Donovan et al. 2021). Residential greenness and asthma About 1 in 12 children in the US suffer from asthma. Although we have medications that can treat symptoms, we do not have any public-health interventions that can cure or prevent the disease. However, emerging evidence suggests that exposing children to greenspace, espe- cially biodiverse greenspace, may help protect children From the U.S. Forest Service and Partners Sustaining Human and Community Health through Urban Forestry by Michelle Kondo, USFS Research Social Scientist; Geoffrey Donovan, USFS Research Forester; Phillip Rodbell, USFS National Program Lead, Urban Forest Research INTRODUCTION Arborists and urban foresters are in the tree business for many personal reasons. Working to build and maintain the tree canopy brings us joy in our service to communities. A healthy tree spreading its beauty and shade on a hot summer day reminds us why we are in this profession, especially when we see people cooling off underneath. Recent studies and findings from the Forest Service have expanded our understanding of the importance of the many benefits that city trees provide. In our gut we knew these to be true, but now we have the science to back it up—and these findings rein- force the value of our service and validate our choice to work in this field. 16 CityTREES