GR Urban Tree Canopy-by GVSU/AWRI

April 2009Project Partners: Grand Rapids Planning Department and JJR, Inc.

TWO GOALS…..Quantify the presence of the urban tree canopyQuantify the presence of the urban tree canopy

How much land area in the city has tree canopy?

Pl t l th l i l i b iPlace a monetary value on the ecological services being provided by urban trees

Can we calculate this for the entire city?

Defined as the layer of tree leaves, branches and stems that cover the ground when viewed fromstems that cover the ground when viewed from above*.

It includes trees growing I di id llIndividuallyin small groupsor under forest conditions

*Chesapeake Bay Program. 2004. Summary: Guidelines for Implementing the Chesapeake Bay Program. Annapolis MD.

Watershed scale*Environmental BenefitsEnvironmental Benefits

Reduce stormwater runoff and floodingImprove regional air qualityImprove soil and water qualityImprove soil and water qualityReduce stream channel erosionProvide habitat for plants and wildlifePreserve native ecotypesPreserve native ecotypesReduce summer air and water temperatures

*Center for Watershed Protection and USDA Forest Service, Northeastern Area State and Private Forestry. 2005. Urban Watershed Forestry Manual. Ellicott City, MD.

Site scale*Economic BenefitsEconomic Benefits

Decrease heating and cooling costsTrees left on site during construction will

Reduce costs related to clearing grading paving mowing andReduce costs related to clearing, grading, paving, mowing, and managing stormwater

Increase property valuesPositively influence consumer behaviory

Environmental BenefitsReduce urban heat island effectEnhance function of stormwater treatmentEnhance function of stormwater treatment


Site scale*Community BenefitsCommunity Benefits

Increase livabilityImprove health and well-beingBlock UV radiationBlock UV radiationProvide shadeBuffer wind and noiseIncrease recreational opportunitiesIncrease recreational opportunitiesAesthetics


Rainfall Interception – individual trees* A mature deciduous canA mature deciduous can

Intercept 500 to 760 gallons of water per yearA mature coniferous tree can

Intercept more than 4000 gallons per yearIntercept more than 4000 gallons per year

Rainfall Interception – forests**Coniferous forests

Capture 15 to 40% of annual precipitationDeciduous forests

Capture 10 to 20% of annual precipitationp p p


**Xiao, Q., E.G. McPherson, S.L. Ustin, M.E. Grismer, and J.R. Simpson. 2000. “Winter Rainfall Interception by Two Mature Open-Grown Trees in Davis, CA” in Hydrological Processes 14, 763-784.

Evapotranspiration* (ET)Represents the combined water loss fromRepresents the combined water loss from

evaporation from soil and plant surfaces and transpiration by plants

Generally coniferous trees have lower transpiration ratesGenerally, coniferous trees have lower transpiration rates than deciduous treesGenerally, a mature tree can transpire 100 gallons per dayA f t f t t k th 1800An acre of mature forest can take up more than 1800 gallons of water every day


A 25” diameter deciduous tree:

within a forest can use 420 gallons of water a dayy

growing in the open can use nearly 1200 gallons of water agallons of water a day

Adapted from: Perry, T.O. 1994. “Size, Design and Management of Tree Planting Sites.” in Watson and Neely, eds. 1994. The Landscape Below Ground. International Society of Arboriculture. Savoy, IL.

*From, Center for Watershed Protection and USDA Forest Service, Northeastern Area State and Private Forestry. 2005. Urban Watershed Forestry Manual. Ellicott City, MD.

Air quality improvements* One large front yard tree can:One large front yard tree can:

Absorb 10 lbs. of air pollutants per year including:4 lbs. of ozone3 lbs. of particulates3 lbs. of particulates

Cleans 330 lbs. of CO2 from the atmosphere through direct sequestration in the trees biomass and reduced power plant emissions due to cooling energy savings

Oxygen release as a byproduct of photosysnthesisA healthy 32’ Ash produces about 260 lb of net oxygen annuallyA typical person consumes 386 lb of oxygen per year


Aesthetics and Other Benefits*Beautification trees add:Beautification, trees add:

Color, texture, line and form to the urban landscapeTree lined residential streets are the single strongest positive influence on scenic quality**positive influence on scenic qualityPrivate property values

People are willing to pay 3 to 7% more for properties with ample trees versus few or no treesample trees versus few or no treesEach front-yard tree is associated with about a 1-percent increase in home sales price***


**Schroeder N W Cannon W N 1983 The esthetic contribution of trees to residential streets inSchroeder, N.W., Cannon, W.N. 1983. The esthetic contribution of trees to residential streets in Ohio towns. Journal of Arboriculture. 9: 237-243.

*** Anderson, L.M., Cordell, H.K. 1988. Residential property values improve by landscaping with trees. Southern Journal of Applied Forestry. 9: 162-166

Compared the value of ecosystem services provided by trees with the costs associated with aprovided by trees with the costs associated with a full service urban forestry program

Ecosystem services benefitsAi lit i t ti t tAir quality improvements, energy conservation, stormwater interception and carbon dioxide reduction

Costs of maintaining the treesI l di l ti i i i ti d i i t ti tIncluding planting, pruning, irrigation, administration, pest control, liability, cleanup, and removal

*USDA Forest Service, Pacific Southwest Research Station. General Technical Report PSW-GTR-202. 2007. Northeast Community Tree Guide, Benefits, Costs, and Strategic Planting. Albany, CA.

ResultsAverage Annual Net Benefits (benefits minus costs)Average Annual Net Benefits (benefits minus costs)

Tree Size Location Net Benefit $$Small Private Yard 5Small Public 9Medium Private Yard 36Medium Public 52Medium Public 52Large Private Yard 85Large Public 113


Result HighlightsBenefits associated with energy savings and increasedBenefits associated with energy savings and increased property value account for the largest proportion of total benefitsPlanting is the greatest cost for trees followed by treePlanting is the greatest cost for trees, followed by tree pruning

tree care expenditures tend to increase with mature tree sizeEnvironmental benefits alone are up to four times tree careEnvironmental benefits alone, are up to four times tree care costsPubic trees produce higher net benefits than private trees


Potential MethodsManual photo interpretation of the tree canopyManual photo interpretation of the tree canopyTraditional remote sensing tools based on spectral signatures

Supervised/unsupervised classificationSupervised/unsupervised classificationFeature extraction automation tools

Feature Analyst - Visual Learning Systems, Inc. of Overwatch Geospatial Textron SystemsGeospatial, Textron Systems

Feature Analyst is an intelligent software agent, that learns by exampleUsing spatial context (surrounding information) asUsing spatial context (surrounding information) as well as spectral reflectance to identify objectsUsing hierarchical learning – sequences of learning passes to remove clutter and add missed features

Learning parameters Identify/Remove Clutter

Learn Learn

Training set 1st extraction

Learn

2nd extraction

Learn

Add missed features

LearnTypical Workflow Continue or

3rd extractionFinal results Accept

Total City Area = 45.3 Sq. MilesTree Canopy Area = 10 029 Acres (15 7 Sq Miles)Tree Canopy Area = 10,029 Acres (15.7 Sq. Miles) Area covered by the urban tree canopy = 34.6%

How many trees? 2,005,800 (estimate)

City/State % Tree CanopyCharlotte, NC 49

Burlington, VT 43

Pittsburgh, PA 38

Atlanta, GA 37

Grand Rapids, MI 35

Montgomery, AL 33

Muskegon, MI 30

( )Boston, MA 29 (22)

Syracuse, NY 24

New York, NY 24 (21)

Providence RI 23Providence, RI 23

Baltimore, MD 20 (25)

Philadelphia, PA 16

Jersey City NJ 12Jersey City, NJ 12

Frederick, MD 12

As established by American ForestsFor metropolitan areas east of the Mississippi River and inFor metropolitan areas east of the Mississippi River and in the Pacific Northwest

Area % Tree Canopy

Average tree cover all zones 40

S b b id ti l 50Suburban residential zones 50

Urban residential zones 25

Central business districts 15

Road Name Tree Canopy (Acres) % - Tree Canopy7th St 3.5 46.1Collindale Ave 4 0 44 6Collindale Ave 4.0 44.6Elmridge Dr 1.8 44.3Oakleigh Rd 5.2 43.9O'Brien Rd 2.0 43.9Perkins Ave 3.2 40.3Bristol Ave 2.2 36.0Camelot Dr 1.8 34.0Maryland Ave 5.4 33.9Covel Ave 6.4 33.0D L k A 1 3 31 7Dean Lake Ave 1.3 31.7Coit Ave 7.6 28.7Aberdeen St 3.7 27.2Ball Ave 4.4 26.83 Mile Rd 5 9 25 03 Mile Rd 5.9 25.0Walker Ave 4.0 23.8Richmond St 6.5 22.7Valley Ave 3.2 22.3Robinson Rd 1.2 21.8Diamond Ave 6.0 21.7College Ave 4.2 21.66th St 1.2 20.6

Developed by American Forests (www.americanforests.org) ( g)

ESRI ArcGISTM extensionEnvironmental and Resource Values Quantified

Air pollution removal quantities and valueCarbon storage quantityStormwater runoff quantity and valueq yWater quality improvements

Does not calc lateDoes not calculate Energy savings valueIncreased property value

Air pollution removal and carbon storage outputoutput

Based on the Urban Forest Effects Model (UFORE)Developed by the USDA Forest Service

Stormwater runoff reduction outputBased on the TR-55 model

Developed by the USDA Natural Resources Conservation Servicep y

Water quality outputBased on the L-THIA model (Long-term Hydrologic Impact Assessment)Assessment)

Developed by Purdue University and U.S. EPA

Tree CanopyTree Canopy

COVER AND USE CLASS ACRES % Cover (Grand Rapids)

R id ti l 7126 24 6Residential 7126 24.6

Trees - Mostly Natural 4629 16.0

Road & Road ROW 4354 15.0

Trees w/ Grass & Turf Understory 3947 13.6

Commercial/Business/Institutional 3376 11.6

Open Space w/ Grass Cover 1635 5.6

Industrial 1623 5.6

Trees w/ Mostly Impervious Understory 1452 5.0

Water Area 457 1 6Water Area 457 1.6

Parking Lots - Impervious 264 0.9

Shrubs w/ Ground Cover 156 0.5

Total Area 29020 100.0

Air PollutantPounds Removed

per year**Money Saved

from Removal*Carbon Monoxide 17,880 $7,631

Ozone 295,023 $906,375

Nitrogen Dioxide 107,281 $329,591Particulate Matter:

Less then 10 microns 196,682 $403,428

Sulfur Dioxide 44,700 $33,546

Total 661,566 $1,680,570

** Based on Air Pollution conditions for the City of Milwaukee, Wisconsin

* Dollars are “externality” costs borne by society due to rising health care expenditures and reduced tourism revenue.

2-year, 24-hour Rainfall event: 2.37 inchesCurve Number of existing conditions: 78gCurve Number if the trees were

replace with buildings: 89Additional Stormwater storage volume

needed if the trees were replaced withbuildings: 67,075,658 ft3

Construction cost per ft3* $5.50 Total Storm ater Sa ings $368 916 122Total Stormwater Savings: $368,916,122 Annual costs based on payments over 20

years at 6% interest $32,163,789 per year

* Construction costs based on the cost to build just an ADS Storm Tech Systemto handle the additional stormwater

April 2008

Amount of Carbon Storedin the Trees 438,494 Metric Tons

CCX – CFI @ $3.60 metric ton $1,578,578Additional Amount Stored

each year 3414 Metric Tonseach year 3414 Metric Tons

CCX – CFI @ $3.60 metric ton $12,290

Chicago Climate ExchangeApril 28th 2008

G h i i i tGreenhouse gas emission registry,reduction, and trading system

51Biological Oxygen demand

Percent Change in Contaminant Loading When Trees are Replaced with Impervious Surfaces

77

63

Chromium

Cadmium

0

82

Copper

Chemical Oxygen demand

utan

t

28

21

Nitrogen

LeadPoll

15

50

58

Zinc

Suspended Solids

Phosphorous

15

0 10 20 30 40 50 60 70 80 90

Zinc

Percent

Air Pollution Removal: $1,680,570 annuallyStormwater Runoff: $368 916 122 or $32 163 789Stormwater Runoff: $368,916,122 or $32,163,789 annuallyCarbon Storage: $1,578,578 (presently stored in the g (p ytrees) or $12,290 worth of storage per yearWater Quality Benefits: $????

THE CITY’S 35 PERCENT TREE CANOPY PROVIDES TOTAL DOLLAR BENEFITS OF:PROVIDES TOTAL DOLLAR BENEFITS OF: $372,175,270

Can we extract the tree canopy into tree species classes?species classes?

Oak, Ash, Maple, Basswood, Pine, etc.Can we calculate the “possible” full extent ofCan we calculate the possible full extent of the tree canopy?

Identify areas that could actually have tree coverIdentify areas that could actually have tree cover minus existing trees and built infrastructureWhat areas are actually viable for tree canopy

How has the tree canopy changed over time?What potential impact could the Elm Ash Borer have on the tree canopy?

Documents

GR Urban Tree Canopy-by GVSU/AWRI