Psychological & Social BenefitsPsychological & Social Benefitsof Trees, Nature &of Trees, Nature & PlantsPlants

Review of Scientific StudiesReview of Scientific Studies

Kathleen L. Wolf, Ph.D.Kathleen L. Wolf, Ph.D.kwolf@ukwolf@u..washingtonwashington..edueduUniversity of WashingtonUniversity of Washington

Global Urbanization

AmericaAmerica’’ss- - wildlands wildlands --places to getplaces to get

away from it allaway from it all

MuirMuirThoreauThoreauLeopoldLeopold

urban plants & nature - benefitsurban plants & nature - benefits & values?& values?

Portland Classical Chinese GardenPortland Classical Chinese Garden

Most cherished in this mundane worldMost cherished in this mundane world

is a place without traffic;is a place without traffic;

truly in the midst of a citytruly in the midst of a city

there can be mountain and forest.there can be mountain and forest.

Wen Zhengming Wen Zhengming (1470-1559)(1470-1559)

OutlineOutline

Community EconomicsCommunity EconomicsMental FunctioningMental FunctioningHealth & Well-BeingHealth & Well-Being

urban forests, landscapes & interiorsurban forests, landscapes & interiors

Maia says:Maia says:science rocks!science rocks!

InteriorscapesInteriorscapesPlants in Buildings:Plants in Buildings:www.plants-in-buildings.comwww.plants-in-buildings.com

Plants for People:Plants for People:www.plants-for-people.orgwww.plants-for-people.org

Plants forPlants for Life:Life:www.www.plantsforlifeplantsforlife.info.info

OutlineOutline

Community EconomicsCommunity EconomicsMental FunctioningMental FunctioningHealth & Well-BeingHealth & Well-Being

urban forests, landscapes & interiorsurban forests, landscapes & interiors

data from > 800 home sales,data from > 800 home sales,large front yard treelarge front yard treeincrease in sales price of homeincrease in sales price of home(0.88% or $1K per $115K home(0.88% or $1K per $115K homevalue) value) Anderson & Cordell, 1988Anderson & Cordell, 1988

various studies, buyers willing to pay 3-various studies, buyers willing to pay 3-7% more for residential properties with7% more for residential properties withample treesample trees

Trees Trees andand Property Values Property Values

proximate principleproximate principle

assessed value of properties -assessed value of properties -10 to 20% higher10 to 20% higher

conditions for higher value:conditions for higher value:forested, passive use,forested, passive use,good visibility, well maintainedgood visibility, well maintained

Parks Parks andand Property Values Property Values

John Crompton, Texas A&M2001, Parks & Econ Dev, APA

Landscape Landscape andand Office Bldg Rents Office Bldg Rents

Landscape Landscape andand Office Bldg Rents Office Bldg RentsBuilding and landscape variationsBuilding and landscape variations–– 85 office buildings85 office buildings–– landscape quantity, functionality,landscape quantity, functionality,

qualityquality

Positive InfluencesPositive Influences–– quality landscape aestheticquality landscape aesthetic–– building shadebuilding shade

OutcomesOutcomes–– 7% boost in rental rates7% boost in rental rates–– plants as visual screens reduce ratesplants as visual screens reduce rates

7.5%7.5%

R.J. Laverne & K. Winson,Davey Resource Group,September 2003, J of Arb

Trust forPublic Lands

AmericanPlanningAssociation

- Inner City Business Districts- Inner City Business Districts- Small Town Business Districts- Small Town Business Districts- Freeway Roadside Commerce- Freeway Roadside Commerce- Athens GA Case Study- Athens GA Case Study

4 national studies4 national studies

National Urban and CommunityNational Urban and CommunityForestry Advisory CouncilForestry Advisory Council

USDA Forest ServiceUSDA Forest Servicelocal community partnerslocal community partners

Research Question:Research Question:

What is the response ofWhat is the response ofconsumers/shoppers toconsumers/shoppers totrees in CBD streetscapes?trees in CBD streetscapes?

Measures:

Visual preference

Place perceptions

Patronage behavior

Product pricing

Trees in Business DistrictsTrees in Business Districts

District visitors prefer (large) treesDistrict visitors prefer (large) trees

Merchant interactions & product qualityMerchant interactions & product quality

judged to be betterjudged to be better

Shoppers willing to pay 9-12% more for productsShoppers willing to pay 9-12% more for products

Results:Results:Visual PreferenceVisual Preference

Small cities - all U.S.A.Small cities - all U.S.A.

Image Categories Image Categories (sorted by ratings)(sorted by ratings)

Full Canopymean 3.63

Pocket Parksmean 3.72

(highest)

Scale : 1=not at all,5=like very much,

26 images

IntermittentTrees2.78

EnclosedSidewalk

3.32

No Trees mean 1.65

(lowest)

(high - 3.72)

Results:Results:Product PricingProduct Pricing

Large cities - all U.S.A.Large cities - all U.S.A.

trees & consumer spendingtrees & consumer spending

Product PricingProduct Pricing

• comparing CBD with andwithout trees

• contingent valuation method

• willingness to pay more for alltypes of goods with trees

* up to 12% in large cities,9% in small cities)

List of Goods &List of Goods & Stated PricesStated Prices

0

5

10

15

20

25

30

35

40

45

50

55

60

65

70

75

conveniencegoods- 50% -

shoppinggoods- 39% -

specialtygoods- 35% -

Goods Categories

Mea

n S

tate

d P

rice

Product PricingProduct Pricing

No Tr ees

Tr ees

Tr ees/Access.

www.www.cfrcfr..washingtonwashington..edu/researchedu/research..envmindenvmind

Journal ofJournal of Forestry, December 2005Forestry, December 2005

OutlineOutlineCommunity EconomicsCommunity EconomicsMental FunctioningMental FunctioningHealth & Well-BeingHealth & Well-Being

urban forests, landscapes & interiorsurban forests, landscapes & interiors

Nature & Learning PotentialNature & Learning Potential

Lecture Halls - plantsLecture Halls - plants–– 34 students34 students–– academic yearacademic year–– lecture halls - withlecture halls - with && w/o plantsw/o plants

Positive AffectsPositive Affects–– less inattentive behavior (70%less inattentive behavior (70%

fewer signals)fewer signals)–– 100% lecture return rate with100% lecture return rate with

plants, 86% withoutplants, 86% without

Amanda Read, Royal College of Agriculture, UK

Workplace Nature ViewsWorkplace Nature Views

Well-beingWell-being–– desk workers without view ofdesk workers without view of

nature reported 23% morenature reported 23% moreailments in prior 6 monthsailments in prior 6 months

Job SatisfactionJob Satisfaction–– less frustrated and moreless frustrated and more

patientpatient–– higher overall job satisfactionhigher overall job satisfaction

and enthusiasmand enthusiasm

Kaplan, R. 1993. The Role of Nature in theWorkplace. Landscape and Urban Planning,26: 193-201.

Plants in WorkplacePlants in WorkplaceProductivityProductivity–– 12% quicker reaction on computer tasks12% quicker reaction on computer tasks–– reports of being more attentivereports of being more attentive

Less StressLess Stress–– lower systolic blood pressurelower systolic blood pressure

Lohr et al. 1996. J. of Environmental Horticulture

employeeemployeehealth & thehealth & thecorner office:corner office:

indirectindirect$$ benefits$$ benefits

Green Roof - Chicago City HallGreen Roof - Chicago City Hall

high-rise nature,high-rise nature,preferred viewspreferred views

Directed Attention FatigueDirected Attention Fatigue

mental tasks requiring high focusmental tasks requiring high focus

and high effortand high effort

active screening of other stimulusactive screening of other stimulus

and distractionsand distractions

depletion - short term & cumulativedepletion - short term & cumulative

AmericaAmerica’’sswildlands wildlands --

getting awaygetting awayfrom it all!from it all!

Being AwayBeing AwayFascinationFascinationExtentExtentCompatibilityCompatibility

Rachel & Stephen Kaplan - University of MichiganRachel & Stephen Kaplan - University of Michigan

Characteristics of Characteristics of Restorative EnvironmentsRestorative Environments

recovery from

directed attention

fatigue

RestorativeRestorativeAffects ofAffects ofNearby NatureNearby Nature- small spaces- small spaces- enclosure- enclosure- sequence of- sequence ofexperienceexperience- rich detailing- rich detailing

Americans travel 2.3 billion miles perAmericans travel 2.3 billion miles perday on urban freeways & highwaysday on urban freeways & highways

Roadside Landscape &Roadside Landscape &Traffic Stress ResponseTraffic Stress Response

Roadside Features - DrivingRoadside Features - DrivingSimulationsSimulations–– Forest, golf course, strip mallForest, golf course, strip mall

Physiological ResponsePhysiological Response–– E.g. heart beat, blood pressureE.g. heart beat, blood pressure

ResultsResults–– Nature scenes - return to baselineNature scenes - return to baseline

faster, less response to new stressorsfaster, less response to new stressors–– Immunization effectImmunization effect

Parsons, R., Tassinary, L., G., Ulrich, R. S., Hebl, M. R., and M. Grossman-Alexander. 1998. The view from the road: Implications for stress recoveryand immunization. Journal of Environmental Psychology 18:113-140.

Stress and Body ResponseStress and Body Response

impaired immune systemimpaired immune system

sleep interruptionsleep interruption

heightened ailments (acne,heightened ailments (acne,

ulcers)ulcers)

more likely to have accidentsmore likely to have accidents

inhibited memoryinhibited memory

Ulrich-views of nature reduce stress response

ChicagoChicagoPublicPublic

HousingHousingwith &with &withoutwithout

greengreenspacesspaces

Wm. SullivanWm. Sullivan& F. & F. KuoKuo

University ofUniversity ofIllinoisIllinois

Human-Environment ResearchHuman-Environment ResearchLaboratory:Laboratory: www.www.herlherl..uiucuiuc..eduedu

lower levels of fearlower levels of fear

less violent & aggressive behaviorless violent & aggressive behavior

fewer reported crimesfewer reported crimes

more self-discipline for girlsmore self-discipline for girls

reduced ADHD symptomsreduced ADHD symptoms

better neighbor relationshipsbetter neighbor relationships

better coping with lifebetter coping with life’’s challengess challenges

OutlineOutlineCommunity EconomicsCommunity EconomicsMental FunctioningMental FunctioningHealth & Well-BeingHealth & Well-Being

urban forests, landscapes & interiorsurban forests, landscapes & interiors

Plants & Office ConditionsPlants & Office ConditionsDust LevelsDust Levels–– particulates reduced 20%particulates reduced 20%–– respiratory effects?respiratory effects?

Relative HumidityRelative Humidity–– recommended range forrecommended range for

human comfort 30-60%human comfort 30-60%–– plants boost relative humidityplants boost relative humidity

significantly, but notsignificantly, but notexcessively (5-10%)excessively (5-10%)

Lohr & Pearson-Mims. 1996.Atmospheric Environment

Wellness & HealingWellness & HealingSurgery RecoverySurgery Recovery–– shorter post-operative staysshorter post-operative stays–– less use of potent pain drugs,less use of potent pain drugs,

better attitudebetter attitude

Lifestyle RecoveryLifestyle Recovery–– attentional attentional fatigue restoredfatigue restored–– relationships and careerrelationships and career

copingcoping

Cimprich, B. 1992. Attentional FatigueFollowing Breast Cancer Surgery.Research in Nursing and Health 15, 199-207

Roger Ulrich. Texas A &M. Studieson nature and medical recovery

Healing GardensHealing Gardens- institutional design -- institutional design -

U of WA Hospitals Surgery PavilionU of WA Hospitals Surgery Pavilion

USFS & Centers for Disease ControlUSFS & Centers for Disease Control

Americans, physical activity & obesityAmericans, physical activity & obesity

Reported Leisure Activity - U.S.Reported Leisure Activity - U.S.

Physical Inactivity & ObesityPhysical Inactivity & Obesity

majority of Americans not active enoughmajority of Americans not active enough

goal-30 minutes per day of moderategoal-30 minutes per day of moderate

activityactivity

risk factor for chronic diseasesrisk factor for chronic diseases

(heart, cancer, diabetes)(heart, cancer, diabetes)

significant costs to national health servicessignificant costs to national health services

Obesity Trends* Among U.S. Adults

BRFSS, 1985

Source: Mokdad A H, et al. J Am Med Assoc 1999;282:16,

2001;286:10.

Obesity Trends* Among U.S. Adults

BRFSS, 1990

Source: Mokdad A H, et al. J Am Med Assoc 1999;282:16,

2001;286:10.

Obesity Trends* Among U.S. Adults

BRFSS, 1991

Source: Mokdad A H, et al. J Am Med Assoc 1999;282:16,

2001;286:10.

Obesity Trends* Among U.S. Adults

BRFSS, 1992

Source: Mokdad A H, et al. J Am Med Assoc 1999;282:16,

2001;286:10.

Obesity Trends* Among U.S. Adults

BRFSS, 1993

Source: Mokdad A H, et al. J Am Med Assoc 1999;282:16,

2001;286:10.

Obesity Trends* Among U.S. Adults

BRFSS, 1994

Source: Mokdad A H, et al. J Am Med Assoc 1999;282:16,

2001;286:10.

Obesity Trends* Among U.S. Adults

BRFSS, 1995

Source: Mokdad A H, et al. J Am Med Assoc 1999;282:16,

2001;286:10.

Obesity Trends* Among U.S. Adults

BRFSS, 1996

Source: Mokdad A H, et al. J Am Med Assoc 1999;282:16,

2001;286:10.

Obesity Trends* Among U.S. Adults

BRFSS, 1997

Source: Mokdad A H, et al. J Am Med Assoc 1999;282:16,

2001;286:10.

Obesity Trends* Among U.S. Adults

BRFSS, 1998

Source: Mokdad A H, et al. J Am Med Assoc 1999;282:16,

2001;286:10.

Obesity Trends* Among U.S. Adults

BRFSS, 1999

Source: Mokdad A H, et al. J Am Med Assoc 1999;282:16,

2001;286:10.

Obesity Trends* Among U.S. Adults

BRFSS, 2000

Source: Mokdad A H, et al. J Am Med Assoc 1999;282:16,

2001;286:10.

Obesity Trends* Among U.S. Adults

BRFSS, 2001

Source: Mokdad A H, et al. J Am Med Assoc 1999;282:16,

2001;286:10.

parks, open spaces & and trailsparks, open spaces & and trails

walkable walkable city placescity places

make room for pedestriansmake room for pedestrians

Economic Development ValuesEconomic Development ValuesEnvironmental Functions/ServicesEnvironmental Functions/ServicesImproved Human Health/FunctioningImproved Human Health/Functioning

Value of Plants and Nature in Cities?Value of Plants and Nature in Cities?

City/Metro ScaleCity/Metro ScaleProperties and NeighborhoodsProperties and Neighborhoods

BuildingBuilding Interiors?Interiors?

Plants are very important for ourPlants are very important for ourquality of life,quality of life,

our mood and our emotional,our mood and our emotional,psychological and physical health.psychological and physical health.

Get Your Greens!Get Your Greens!

where we live, work &where we live, work &learnlearn & play& play