Trees and Public Health: Growing a Healthy Human Habitat

Trees and Public Health: Growing a Healthy Human Habitat Frances E. (Ming) Kuo University of Illinois, Urbana-Champaign CA Public Health, 2010

Thanks to … • Andrea Faber Taylor • Rebekah Coley, Liesette Brunson, Stephen DePooter, Malen Bacaicoa, Ann Schlosser, ByoungSuk Kweon, Angela Wiley, Irene Miles, Lisa Canin, William Sullivan, Johanna Weber, XiaoYing Wang, Xinlin Yu • US Forest Service and NUCFAC, CREES • US HUD

Trees and Public Health

Trees and Public Health What do trees have to do with public health? • Nothing • Something • Everything

Nothing

Nothing • They’re pretty • They cause allergies, drop limbs on people • Funding for greening is funding that could have gone towards health promotion

Something

Something • They clean our air • They clean our water • They help prevent flooding • They reduce urban heat island effects • Parks support recreation

Everything

Everything • They are essential components of a healthy human habitat • They enable us to thrive – socially, physically, psychologically • Funding for greening is funding for health promotion

Trees and other natural elements as essential to a healthy human habitat

Trees, other Natural Elements as Essential • Why ask? • How would we tell? • Overview of the evidence • The evidence is actionable • What the evidence is telling us

Trees and other natural elements as essential to a healthy human habitat:Why ask?

Why ask? Humans evolved in nature • Primates appear 65 mya • Hominids appear 5 mya • Tool use appears 2 mya • 10-15,000 years ago, Homo sapiens begin to cultivate crops, settle into villages • 99.5% of the last 2M years embedded in the natural environment

Why ask? Mobile organisms are drawn toward fit habitats • Habitat selection theory • Environmental preference as a marker for fit habitat

Why ask? What environments are humans drawn to?

Why ask? Humans are drawn toward environments with trees and other natural elements • A strong and ubiquitous finding • 25 years of landscape preference research

Thus, we suspect that trees and other natural elements might be essential to a healthy human habitat

How would we tell?

How would we tell? Hints from ethology, laboratory animals, and zoos • Organisms are attuned to their habitats in subtle and powerful ways

How would we tell? Hints from ethology, laboratory animals, and zoos • Organisms are attuned to their habitats in subtle and powerful ways • Organisms housed in unfit habitats undergo social, psychological, and physical breakdown

How would we tell? The signs • IF trees and other natural elements are essential elements of a healthy human habitat, • THEN we would expect humans deprived of nature to undergo social, psychological, and physical breakdown

How would we tell? Three challenges

How would we tell? Three challenges • Compare humans in conditions varying in greenness • Intensity of greenness • Proximity of trees and other green elements • Exposure to green views, places

Robert Taylor Homes “low green” Robert Taylor Homes “high green”

Ida B. Wells “low green” Ida B. Wells “high green”

How would we tell? Three challenges • Compare humans in conditions varying in greenness

How would we tell? Three challenges • Compare humans in conditions varying in greenness • Hold other variables constant

How would we tell? Three challenges • Compare humans in conditions varying in greenness • Hold other variables constant • Look for signs of social, psychological, physical breakdown

Are green places and views essential to a healthy human habitat?

Overview of the Evidence

Overview of the Evidence Social Breakdown

Overview of the Evidence Social Breakdown  Strength of community  Courtesy, mutual support  Supervision of children outdoors  Graffiti, noise, litter  Loitering, illegal activity  Property Crime  Aggression, violence  Violent Crime

Overview of the Evidence Social Breakdown  Strength of community  Courtesy, mutual support  Supervision of children outdoors  Graffiti, noise, litter  Loitering, illegal activity  Property Crime Aggression, violence Violent Crime

Overview of the Evidence Aggression, Crime • Compare humans in conditions varying in greenness:

Overview of the Evidence Aggression, Crime • Compare humans in conditions varying in greenness: low vs. high green

Overview of the Evidence Aggression, Crime • Compare humans in conditions varying in greenness • Hold other variables constant:

Overview of the Evidence Aggression, Crime • Compare humans in conditions varying in greenness • Hold other variables constant: • randomly assign people to buildings • architecturally identical buildings • landscaping is not up to residents • check to see low and high green people are the same

Overview of the Evidence Aggression, Crime • Compare humans in conditions varying in greenness • Hold other variables constant • Look for signs of social, psychological, physical breakdown:

Overview of the Evidence Aggression, Crime • Compare humans in conditions varying in greenness • Hold other variables constant • Look for signs of social, psychological, physical breakdown • self-reported aggression, physical aggression, violence, and severe violence • police crime data by address

Overview of the Evidence Aggression, Crime • Significantly more total aggression, physical aggression, violence, and severe violence in “low green” buildings • Aggression tied to mental fatigue • Significantly more total crime, property crime, violent crime in “low green” buildings – • Explains 7% of variance in crime

Overview of the Evidence Social Breakdown  Strength of community  Courtesy, mutual support  Supervision of children outdoors  Graffiti, noise, litter  Loitering, illegal activity  Property Crime  Aggression, violence  Violent Crime

Overview of the Evidence Psychological Breakdown

Overview of the Evidence Psychological Breakdown  Attention  Learning  Management of major life issues  Impulse control  Delay of gratification  Well-being (mood, life satisfaction)  AD/HD symptoms

Trees and Public Health: Growing a Healthy Human Habitat