146 Townsend et al.: Exploring the Relationship Between Trees and Human Stress Arboriculture & Urban Forestry 2016. 42(3): 146–159 Exploring the Relationship Between Trees and Human Stress in the Urban Environment Joseph B. Townsend, Thomas W. Ilvento, and Susan S. Barton Abstract. The research literature describes a positive relationship between seeing plants and human well-being. More rapid recov- ery from surgery, reduced incidence of neighborhood crime, increased baby birth weight, and increased trust of neighbor- hood merchants are among the benefits attributed to exposure to trees and shrubs. This study attempted to find a common expla- nation for these outcomes. It examined the connection between urban trees and neighborhood stress. Each of the stated outcomes can be attributed, in part, to stress reduction. The literature indicated that stress reduction is one of the consequences of exposure to plants. Stress levels were measured at the block level in Wilmington, Delaware, U.S., by means of a survey mailed to 2,704 resi- dents. Physical conditions were catalogued using an on-site inventory. The survey and inventory demonstrated that the total num- ber of trees on a block has a strong negative relationship with neighborhood stress and a positive relationship with self-reported health. The results suggest that moderation of stress is one of the factors that underlies the beneficial consequences of expo- sure to green vegetation on inner-city blocks. This research should prove useful to city planners and urban residents alike. Key Words. Cross-reference Directory; Delaware; Hassles and Upliſts Scale; Human Stress; Perceived Stress Scale; Street Trees; Survey; Tailored Design Method; Tree Canopy; Tree Inventory; Wilmington. Previous studies have documented the contribu- tion of urban trees to the physical environment in cities. Beneficial impacts include pollen reduction (Nowak and McPherson 1993), carbon seques- tration (Nowak and McPherson 1993; Cairns and Meganck 1994), reduction of rainwater run- off (Tyrväinen et al. 2005), sound reduction (Pathak et al. 2007), and ambient temperature moderation (Bolund and Hunhammar 1999). The behavioral impact of tree cover is more dif- ficult to quantify than the physical impact. Never- theless, data exists to show that views of greenery impact individual well-being and public health (Comas et al. 2010). For example, views of trees have been shown to improve health outcomes (Ulrich 1984), street trees improve the shopping experience (Wolf 2004), landscaping around public housing projects reduces negative social behavior (Kuo and Sullivan 2001a), and the presence of trees on residential streets has a negative correlation with crime rate (Donovan and Prestemon 2010). Two distinct lines of research run through the literature on the psychological effects of green land- ©2016 International Society of Arboriculture scaping. The first line takes the individual approach. The second examines the effect of tree canopy on the community. Roger Ulrich was one of the first to describe the calming effect natural landscapes have on stressed individuals (Ulrich et al. 1991). He used such physiological measures as heart rate, muscle tension, and skin conductance to measure individ- ual stress. Today, this line of research is expanding to include blood and saliva sampling to determine cortisol levels (Lee et al. 2012; Jiang et al. 2014). In contrast, Kuo and Sullivan (2001b) examined the crime rate at Chicago, Illinois, U.S., housing projects by comparing the aggregated crime rate of an entire building with the presence or absence of exterior landscaping. This research follows the second line by comparing the level of neighborhood stress to the amount of tree cover on a residential city block. Stress, stressors, and the stress response are terms oſten confused in common parlance. For this study, stress and stressor are considered synony- mous terms. They can be compared to a heavy truck on a metal bridge. The truck, sometimes referred to as the load, is the stressor, it provides stress. The
May 2016
| Title Name |
Pages |
Delete |
Url |
| Empty |
Ai generated response may be inaccurate.
Search Text Block
Page #page_num
#doc_title
Hi $receivername|$receiveremail,
$sendername|$senderemail wrote these comments for you:
$message
$sendername|$senderemail would like for you to view the following digital edition.
Please click on the page below to be directed to the digital edition:
$thumbnail$pagenum
$link$pagenum
Your form submission was a success.
Downloading PDF
Generating your PDF, please wait...
This process might take longer please wait
