Dept. of Horticulture
Washington State University

Human Well-Being Promoted By Trees, Especially Those With Preferred Forms

Scenes with added
People respond psychologically and physiologically to urban and natural landscapes. Natural scenes elicit greater calming responses than urban scenes. Viewing trees in urban landscapes has been associated with improved health. Different components of nature might promote different human responses. People respond differently to trees than to other elements in nature. People also prefer particular tree forms, such as the low, spreading form of savanna trees. The objectives of this research were to compare people's responses to urban scenes containing trees of different forms or inanimate objects.

Subjects' psychological and physiological states were monitored while viewing individual computer-enhanced slides of urban scenes with inanimate objects or conical, globose, or spreading tree forms. Emotional states were measured with a self-report survey. Blood pressure and skin temperature were measured. Aesthetic preference for each scene being viewed also was evaluated. 

People reported more positive emotions, such as friendliness, and fewer negative emotions, such as sadness, when looking at urban scenes with trees than when looking at the same scenes containing inanimate objects. In some cases, the positive emotions reported were magnified when viewing the spreading tree. Scenes with inanimate objects were rated the least attractive, while those with the spreading trees were rated the most attractive. There were no significant differences in blood pressure or skin temperature. However, trends were similar to those for emotional responses. People tended to be more relaxed when looking at scenes with trees than those with inanimate objects, and the response was accentuated with the spreading tree form.

Graph of positive emotional responsesGraph of negative
                  emotional responses

People responded more positively to trees with conical, globose, or spreading forms in urban settings than to the same settings with inanimate objects. These results support the importance of using trees of any form to enhance urban environments. Positive responses were intensified for trees with spreading forms. Spreading trees may be important in areas, such as healthcare facilities, where people are confined for extended periods.

This research was partially supported by the Idaho Department of Lands.

Full study reported in:
Lohr, V.I. and C.H. Pearson-Mims. 2006.  Responses to scenes with spreading, rounded, and conical tree forms.  Environment & Behavior 38(5):667-688. Abstract

Virginia Lohr (E-mail:
Department of Horticulture
Washington State University
Pullman, Washington 99164-6414 U.S.A.

Updated March 20, 2015