Environmental Benefits Analysis of Public Trees for

Delaware, Ohio

T. Davis Sydnor and Sakthi Subburayalu

School of Environment and Natural Resources

December 11, 2012

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An Analysis of Tree Benefits for Delaware, Ohio Public Trees

EXECUTIVE SUMMARY

An inventory of public trees in the City of Delaware, Ohio was conducted by Ohio State University Extension,

Delaware County Master Gardner Volunteers, and the Delaware City GIS Coordinator. The survey identified 12,464

existing public street trees which were inventoried during the 2010 to 2012 growing seasons. A common bid price for

this service is $4.00 per inventoried tree and thus the inventory represents a value of nearly $50,000. Most

importantly, however, is that the community now has a tree inventory and GIS tree database in a form that can be used

to better manage the tree resources of the city. Benefits mentioned above do not include the value of the subsequent

analysis and report by The Ohio State University’s School of Environment and Natural Resources which would

conservatively add another $11,500. Analysis of the inventory data was done using iTree, a software suite distributed

by the USDA Forest Service. The specific program in the iTree suite used to identify tree benefits was iStreets. This

program allows community leaders the ability to make informed decisions about Delaware’s green infrastructure or to

explore many aspects including biodiversity and values of environmental services such that environmental benefits

can be managed or enhanced to reduce costs and the community’s carbon footprint.

A long standing rule of thumb for taxonomic biodiversity in the urban forest is the 10:20:30 guideline which suggests

that no more than 10 percent of trees should be from the same species, no more than 20 percent should be from the

same genera, and no more than 30 percent should be from the same family. In Delaware, maple trees (30%) greatly

exceed genus and even family guidelines (Table 1). We recommend against any further plantings of maples to protect

against future concerns. Callery pear plantings might be reduced as it is a seriously invasive exotic tree.

Ashes are a separate issue due to emerald ash borer (EAB). Ashes represent an estimated 320 individuals or 2.8 % of

the public trees (Table 4). This represents a loss of 3.1% of the Delaware’s canopy if EAB should destroy all

American ashes as predicted. Based on the inventory and estimates, ash removal costs in Delaware would likely

exceed $131,000. Replacement costs add another $92,000 more for a grand total of more than $222,000. Ash

removal and/or treatment costs will need to be addressed by informed community leaders. Ohio State University

Extension can assist in developing informed plans including costs and probabilities of various treatment options vs. no

treatment. There is no single answer for communities facing this problem.

Larger growing deciduous trees now constitute 53% of Delaware’s tree canopy and should be used to replace the

ashes. Native suggestions, poorly represented now, include Kentucky coffeetree; Shumard, swamp white, and

chinquapin oaks; American sycamore; buckeye; basswood; catalpa; and sweetgum. Introduced species can be used as

well if desired and if their use is consistent with community goals.

Under ideal situations tree numbers among various size classes should be similar and then decline as trees reach their

mature size and older trees die. Smaller-sized trees (<12-in) of large growing species represent 87%. (Tables 2 and 3)

of Delaware’s street trees. Comparing the importance value of 647 silver maples (18.1%) against 1285 Freeman

maples with an importance value of 8.2% and you see that environmental benefits are four times higher for the larger

silver maples. Delaware will benefit greatly by allowing recently planted trees to grow (Table 4). Smaller growing

crabapples and cherries (plums) generally produce few environmental benefits relative to their larger growing

counterparts. This reinforces the need for planting and retaining larger statured trees such as preferred in a Toledo,

OH resident preference survey to increase the environmental benefits of Delaware’s tree canopy.

A major benefit of urban trees is their ability to intercept rainfall and reduce storm water runoff (Table 5). Storm

water runoff is a major cost for Ohio communities. Columbus, OH is embarking on a multi-billion dollar sewer and

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storm water upgrade for the community. Putting that into a local context, Delaware public trees intercept more than 6

million gallons of storm water annually at a savings to the community of more than $167,000 dollars per year. This

could be increased with strategic planting of larger-statured trees or retaining the recently planted ones.

Carbon sequestration, as reported here, represents the carbon removed from the air and stored in the trees over time

(Table 6). Nearly 16 million pounds or 8,000 tons of carbon have been stored by Delaware’s street trees over time. In

aggregate, Delaware’s trees are estimated to sequester and avoid more than 3.2 million lbs of CO2 yearly (Table 8)

and would represent carbon credits worth $24 thousand per year if a carbon trading system were in place. These are

net gain figures and include deductions for tree losses and maintenance. Annual CO2 benefits vary by species and size

ranging from $8 to $1.75 but average $1.95 per tree per year. Again the larger silver maples yield more at $8 per tree

per year. Strategic plantings and retentions could increase this over time and become a significant tool in reducing

Delaware’s carbon footprint if desired.

Energy savings by trees are particularly important in view of the citizenry’s increasing concern over the nation’s

energy dependency. Energy is saved by shading structures, evaporating water (evapotranspiration) and reducing wind

speed around structures (Table 7). Delaware trees save the community $67,000 in electricity and $126 ,000 in natural

gas for a total savings of $193,000. This averages more than $15 per tree per year. Retaining larger trees, where

possible, will enhance energy savings at the community level in time.

Annual air quality savings (reduced ozone, nitrous and sulfur oxides as well as particulate matter) for the trees exceeds

$29,000 (Table 9). This includes both direct savings ($4,200) and avoided pollution which is much greater at

$26,500. Avoided pollution is pollution not generated at a power source because energy was not required (avoided)

by the community. The total annual air quality benefits are discounted by $1,600 for the volatile emissions (BVOC)

generated by the trees themselves.

Aesthetic and miscellaneous benefits from Delaware’s trees contribute nearly $225,000 annually in the form of

increased recreational opportunities, increased property values, and enhanced community identity among other things

(Table 10). Research in public housing has shown that areas with trees facilitate interaction among residents and lead

to reduced domestic violence and more sociable environments. Customer surveys suggest that customers prefer to

spend their money and time in commercial streetscapes with trees and are willing to spend up to 11% more in such an

environment.

When all annual benefits are included the 12,464 trees that were inventoried contribute an average of $47 per tree

annually to the community (Table 11). Species vary in their annual benefits but mature size, longevity, and

maintenance costs are but some of the factors determining annual benefits. This would be well in excess of their

maintenance and planting costs for Delaware’s trees.

The Delaware budget for trees maintenance was estimated to be $69,000 based on the budget of $2.00 per capita

required for Tree City USA status by the National Arbor Day Foundation and Delaware’s population of 34,753 people

(2010 Census). Thus while the 12,464 trees require relatively little care per year they deliver $639,000 in annual

benefits from storm water abatement, carbon sequestration, energy savings, air quality enhancement, aesthetic

benefits, and the like (Table 12). Thus the trees in Delaware deliver a 926% return on your investment in tree care.

Returns appear high but Ohio communities studied routinely discover returns on their tree maintenance dollars of 2-

300% and Toledo had a 436% annual return with one of the larger tree maintenance budgets in Ohio. Further, unlike

most community infrastructure, annual tree benefits per tree continue to increase over a tree’s lifetime.

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Table 1. Species Distribution of the Most Common Trees in Delaware,

Ohio Arranged from Most to Least Commonly Seen

Species Percent

Freeman maple 10.3

Honeylocust 7.2

Red maple 7.0

Norway maple 6.9

Northern red oak 6.6

Sugar maple 5.7

Callery pear 5.4

Silver maple 5.2

Littleleaf linden 4.9

Maple 4.4

OTHER SPECIES 36.4

Total 100.0

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Table 2. Relative Age Distribution of the 10 Most Commonly Planted

Trees in Delaware, Ohio as a Percentage (%) of each Tree by Common

Names

Species 0-3 3-6 6-12 12-18 18-24 24-30 30-36 36-42 >42

Freeman maple 16.7 59.8 22.0 1.2 0.1 0.2 0.1 0.0 0.0

Honeylocust 22.8 28.8 44.7 3.4 0.1 0.2 0.0 0.0 0.0

Red maple 20.4 48.3 27.0 2.8 1.0 0.2 0.1 0.1 0.0

Norway maple 12.1 44.2 38.2 3.4 1.6 0.5 0.1 0.0 0.0

Northern red oak 44.5 34.8 16.8 2.2 0.7 0.4 0.4 0.0 0.2

Sugar maple 33.3 30.0 17.3 6.5 8.8 3.1 0.8 0.1 0.0

Callery pear 3.4 15.5 66.2 14.0 0.7 0.0 0.0 0.0 0.1

Silver maple 0.3 8.8 33.8 13.9 13.0 12.5 11.4 4.2 2.0

Littleleaf linden 35.9 43.8 18.0 1.8 0.5 0.0 0.0 0.0 0.0

Unknown Maple 19.9 44.8 22.5 7.1 3.7 1.1 0.7 0.2 0.0

Citywide total 23.3 36.3 30.5 4.9 2.4 1.3 0.8 0.3 0.2

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Table 3. Population of Delaware Public Trees by Common Name,

Tree Type and Size (DBH) Class.

Species DBH Class (in)

0-3 3-6 6-12 12-18

18-24 24-30

30-36 36-42

>42 Total

Broadleaf Deciduous Large (BDL)

Freeman maple 215 768 283 15 1 2 1 0 0 1,285

Red maple 179 424 237 25 9 2 1 1 0 878

Northern red oak 365 286 138 18 6 3 3 0 2 821

Sugar maple 235 212 122 46 62 22 6 1 0 706

Silver maple 2 57 219 90 84 81 74 27 13 647

Maple 109 245 123 39 20 6 4 1 0 547

Linden 156 222 138 11 16 1 1 0 1 546

Sawtooth oak 132 215 67 1 1 0 0 0 0 416

Silver linden 108 62 4 1 0 0 0 0 0 175

Sweetgum 2 19 111 19 4 0 0 0 0 155

BDL OTHER 127 107 84 40 41 34 7 4 7 451

Total

1,630 2,617

1,526 305 244 151 97 34 23 6,627

Broadleaf Deciduous Medium (BDM)

Honeylocust 205 259 402 31 1 2 0 0 0 900

Norway maple 105 382 330 29 14 4 1 0 0 865

Callery pear 23 105 449 95 5 0 0 0 1 678

Littleleaf linden 217 265 109 11 3 0 0 0 0 605

Ash 10 97 182 23 4 1 1 1 1 320

Hedge maple 30 74 132 10 0 0 0 0 0 246

Ginkgo 168 9 4 0 0 1 0 0 0 182

Elm 69 24 50 0 0 0 0 0 0 143

BDM OTHER 218 171 80 19 9 7 1 2 1 508

Total

1,045 1,386

1,738 218 36 15 3 3 3 4,447

Broadleaf Deciduous Small (BDS)

Flowering crabapple 67 172 258 39 3 0 0 0 0 539

Japanese tree lilac 42 133 140 0 0 0 0 0 0 315

BDS OTHER 75 167 117 28 9 2 0 0 0 398

Total 184 472 515 67 12 2 0 0 0 1,252

Continued below

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Broadleaf Evergreen Small (BES)

BES OTHER 0 1 0 0 0 0 0 0 0 1

Total 0 1 0 0 0 0 0 0 0 1

Conifer Evergreen Large (CEL)

CEL OTHER 41 40 20 18 2 0 0 0 1 122

Total 41 40 20 18 2 0 0 0 1 122

Conifer Evergreen Medium (CEM)

CEM OTHER 1 4 0 4 0 0 0 0 0 9

Total 1 4 0 4 0 0 0 0 0 9

Conifer Evergreen Small (CES)

CES OTHER 0 0 1 4 1 0 0 0 0 6

Total 0 0 1 4 1 0 0 0 0 6

Citywide Total 2,901 4,520 3,800 616 295 168 100 37 27 12,464

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Table 3A Estimated Expenses for Ash Removal / Replacement

of Delaware Public Trees due to Emerald Ash Borer

SIZE NUMBER REMOVAL COSTS PER TREE

REMOVAL TOTALS

REPLACEMENT COST

REMOVAL W/ REPLACEMENT

1-3 10 $100 $1,000 $200 $3,000

3-6 97 $375 $36,375 $290 $64,505

6-12 182 $375 $68,250 $290 $121,030

12-18 23 $675 $15,525 $290 $22,195

18-24 4 $675 $2,700 $290 $3,860

24-30 1 $1,290 $1,290 $290 $1,580

30-36 1 $1,625 $1,625 $290 $1,915

36-42 1 $2,150 $2,150 $290 $2,440

>42 1 $2,150 $2,150 $290 $2,440

TOTALS 320 REMOVAL ONLY

TOTALS $131,065

REMOVE + REPLACE TOTALS

$222,965

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Table 4. Delaware, Ohio Public Trees Listed by Common Name from

Greatest to Least Importance Value.

Species Number of Trees

% of Total Trees

Leaf Area (ft2)

% Total Leaf Area

Canopy Cover (ft2)

% of Total

Canopy Cover

Importance Value

Silver maple 647 5.2 2513991 31.6 730337 19.3 18.7

Freeman maple 1285 10.3 593944 7.5 254133 6.7 8.2

Sugar maple 706 5.7 683513 8.6 252837 6.7 7.0

Honeylocust 900 7.2 337413 4.2 329582 8.7 6.7

Callery pear 678 5.4 483442 6.1 283744 7.5 6.3

Norway maple 865 6.9 383327 4.8 238651 6.3 6.0

Red maple 878 7.0 306779 3.9 219865 5.8 5.6

Maple 547 4.4 334884 4.2 177900 4.7 4.4

Northern red oak 821 6.6 191175 2.4 137865 3.6 4.2

Linden 546 4.4 192459 2.4 101382 2.7 3.2

Flowering crabapple 539 4.3 97429 1.2 127780 3.4 3.0

Ash 320 2.6 203914 2.6 118224 3.1 2.8

Littleleaf linden 605 4.9 100164 1.3 68371 1.8 2.6

Sawtooth oak 416 3.3 62577 0.8 65764 1.7 2.0

Hedge maple 246 2.0 117862 1.5 82720 2.2 1.9

Japanese tree lilac 315 2.5 35328 0.4 57283 1.5 1.5

Sweetgum 155 1.2 104171 1.3 56634 1.5 1.4

Elm 143 1.1 33543 0.4 24899 0.7 0.7

Silver linden 175 1.4 9332 0.1 9551 0.3 0.6

Ginkgo 182 1.5 4455 0.1 4402 0.1 0.5

OTHER TREES 1495 12.0 1154448 14.5 441790 11.7 12.7

Total 12464 100.0 7944150 100.0 3783715 100.0 100.0

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Table 5. Annual Storm Water Benefits for Delaware, Ohio

Trees by Species Ordered by Decreasing Benefits/Tree.

Species

Total Rainfall

Interception (Gal)

Total ($) % Total

Tree Numbers

% of Total

$

Avg. $/tree

Silver maple 1695594 $45,954 5.2 27.4 $71.03

Callery pear 430456 $11,666 5.4 7.0 $17.21

Sugar maple 437306 $11,852 5.7 7.1 $16.79

Ash 179920 $4,876 2.6 2.9 $15.24

Sweetgum 85925 $2,329 1.2 1.4 $15.02

Maple 263223 $7,134 4.4 4.3 $13.04

Hedge maple 109078 $2,956 2.0 1.8 $12.02

Norway maple 351172 $9,517 6.9 5.7 $11.00

Honeylocust 363446 $9,850 7.2 5.9 $10.94

Freeman maple 476294 $12,908 10.3 7.7 $10.05

Red maple 285833 $7,747 7.0 4.6 $8.82

Linden 154820 $4,196 4.4 2.5 $7.68

Elm 34043 $923 1.2 0.6 $6.45

Northern red oak 185739 $5,034 6.6 3.0 $6.13

Flowering crabapple 110056 $2,983 4.3 1.8 $5.53

Sawtooth oak 77169 $2,091 3.3 1.3 $5.03

Littleleaf linden 97456 $2,641 4.9 1.6 $4.37

Japanese tree lilac 46470 $1,259 2.5 0.8 $4.00

Silver linden 11268 $305 1.4 0.2 $1.74

Ginkgo 4992 $135 1.5 0.1 $0.74

OTHER STREET TREES 781969 $21,193 12.0 12.7 $14.18

CITYWIDE TOTAL 6182229 $167,550 100.0 100.0 $13.44

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Table 6. Stored CO2 Benefits in Public Trees in Delaware, Ohio

by Species Ordered by Decreasing Benefits per Tree

Species Total stored

CO2 (lbs) Total ($)

% Total Tree

Numbers

% of Total

$

Avg. $/tree

Silver maple 5,528,044 $41,460 5.2 34.7 $64.08

Sugar maple 1,328,545 $9,964 5.7 8.3 $14.11

Sweetgum 218,483 $1,639 1.2 1.4 $10.57

Callery pear 915,828 $6,869 5.4 5.7 $10.13

Ash 393,939 $2,955 2.6 2.5 $9.23

Maple 578,388 $4,338 4.4 3.6 $7.93

Norway maple 736,178 $5,521 6.9 4.6 $6.38

Linden 441,809 $3,314 4.4 2.8 $6.07

Hedge maple 198,201 $1,487 2.0 1.2 $6.04

Flowering crabapple 404,421 $3,033 4.3 2.5 $5.63

Red maple 550,395 $4,128 7.0 3.5 $4.70

Honeylocust 539,236 $4,044 7.2 3.4 $4.49

Northern red oak 435,273 $3,265 6.6 2.7 $3.98

Japanese tree lilac 151,332 $1,135 2.5 1.0 $3.60

Freeman maple 596,565 $4,474 10.3 3.7 $3.48

Elm 61,438 $461 1.2 0.4 $3.22

Littleleaf linden 228,053 $1,710 4.9 1.4 $2.83

Sawtooth oak 122,236 $917 3.3 0.8 $2.20

Silver linden 2,617 $155 1.4 0.1 $0.88

Ginkgo 11,157 $84 1.5 0.1 $0.46

OTHER STREET TREES 1,130,851 $18,698 12.0 15.6 $12.51

CITYWIDE TOTAL 15,953,237 $119,649 100.0 100.0 $9.60

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Table 7. Annual Energy Benefits of Delaware Public Trees by

Common Name and Decreasing Energy Benefits per Tree

Species Total

Electricity (MWh)

Electricity ($)

Total Natural

Gas (Therms)

Natural Gas ($)

Total ($) % Total

Tree Numbers

% of Total $

Avg. $/tree

Silver maple 140.7 $10,676 18587 $18,216 $28,892 5.2 15.0 $44.66

Callery pear 75.2 $5,709 11282 $11,056 $16,765 5.4 8.7 $24.73

Sweetgum 15.4 $1,169 2265 $2,220 $3,389 1.2 1.8 $21.86

Ash 30.6 $2,323 4702 $4,608 $6,931 2.6 3.6 $21.66

Honeylocust 77.6 $5,887 11532 $11,301 $17,188 7.2 8.9 $19.10

Hedge maple 20.0 $1,515 2889 $2,831 $4,345 2.0 2.3 $17.66

Sugar maple 57.1 $4,334 7791 $7,635 $11,969 5.7 6.2 $16.95

Norway maple 61.8 $4,694 9655 $9,462 $14,156 6.9 7.3 $16.37

Maple 41.7 $3,165 5800 $5,684 $8,849 4.4 4.6 $16.18 Flowering crabapple 30.9 $2,346 5062 $4,961 $7,307 4.3 3.8 $13.56

Red maple 52.3 $3,971 7530 $7,379 $11,351 7.0 5.9 $12.93

Linden 26.4 $2,001 4022 $3,941 $5,942 4.4 3.1 $10.88

Elm 6.5 $490 1046 $1,025 $1,515 1.2 0.8 $10.60

Japanese tree lilac 13.5 $1,021 2328 $2,281 $3,302 2.5 1.7 $10.48

Freeman maple 61.1 $4,635 8711 $8,537 $13,172 10.3 6.8 $10.25

Northern red oak 33.4 $2,539 4837 $4,741 $7,279 6.6 3.8 $8.87

Sawtooth oak 16.0 $1,212 2326 $2,280 $3,492 3.3 1.8 $8.39

Littleleaf linden 18.9 $1,435 2852 $2,795 $4,231 4.9 2.2 $6.99

Silver linden 2.7 $202 418 $409 $611 1.4 0.3 $3.49

Ginkgo 1.1 $81 167 $164 $245 1.5 0.1 $1.34 OTHER STREET TREES 101.9 $7,737 14823 $14,527 $22,263 12.0 11.5 $14.89

CITYWIDE TOTAL 884.6 $67,141 128625 $126,052 $193,193 100.0 100.0 $15.50

Table 8. Annual Carbon Dioxide Benefits of Delaware, Ohio Trees by Common

Name and Ordered by Decreasing Benefits per Tree

Species Sequestered

(lb) Sequestered

($) Decomp.

Release(lb)

Maint. Release

(lb)

Total Release

($)

Avoided (lb)

Avoided ($)

Net Total (lb)

Total ($) % Total

Tree Numbers

% of Total

$

Avg. $/tree

Silver maple 493686 $3,703 -26575 -1505 -$211 235941 $1,770 701548 $5,262 5.2 21.7 $8.13

Callery pear 149731 $1,123 -4471 -794 -$39 126164 $946 270631 $2,030 5.4 8.4 $2.99

Ash 61214 $459 -1959 -344 -$17 51336 $385 110247 $827 2.6 3.4 $2.58

Sweetgum 22364 $168 -1049 -189 -$9 25834 $194 46960 $352 1.2 1.5 $2.27

Sugar maple 105614 $792 -6538 -680 -$54 95781 $718 194177 $1,456 5.7 6.0 $2.06

Honeylocust 113352 $850 -2745 -730 -$26 130102 $976 239980 $1,800 7.2 7.4 $2.00

Norway maple 130248 $977 -3806 -743 -$34 103743 $778 229441 $1,721 6.9 7.1 $1.99

Hedge maple 29598 $222 -953 -223 -$9 33475 $251 61897 $464 2.0 1.9 $1.89

Maple 67436 $506 -2782 -469 -$24 69947 $525 134132 $1,006 4.4 4.1 $1.84

Freeman maple 146940 $1,102 -3412 -866 -$32 102436 $768 245098 $1,838 10.3 7.6 $1.43

Red maple 76485 $574 -2652 -644 -$25 87768 $658 160957 $1,207 7.0 5.0 $1.37

Flowering crabapple 48360 $363 -1944 -500 -$18 51840 $389 97756 $733 4.3 3.0 $1.36

Elm 13866 $104 -315 -86 -$3 10837 $81 24302 $182 1.2 0.8 $1.27

Linden 42170 $316 -2127 -400 -$19 44211 $332 83854 $629 4.4 2.6 $1.15

Littleleaf linden 52094 $391 -1262 -355 -$12 31722 $238 82200 $617 4.9 2.5 $1.02

Japanese tree lilac 21353 $160 -728 -250 -$7 22564 $169 42938 $322 2.5 1.3 $1.02

Northern red oak 46358 $348 -2104 -480 -$19 56102 $421 99877 $749 6.6 3.1 $0.91

Sawtooth oak 23037 $173 -592 -235 -$6 26777 $201 48988 $367 3.3 1.5 $0.88

Silver linden 3258 $24 -103 -64 -$1 4455 $33 7546 $57 1.4 0.2 $0.32

Ginkgo 1065 $8 -56 -46 -$1 1781 $13 2744 $21 1.5 0.1 $0.11

OTHER STREET TREES 194055 $1,455 -12091 -1381 -$101 170978 $1,282 351561 $2,637 12.0 10.9 $1.76

CITYWIDE TOTAL 1842284 $13,817 -78264 -10984 -$669 1483796 $11,128 3236832 $24,276 100.0 100.0 $1.95

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Table 9. Annual Air Quality Benefits of Delaware, Ohio Trees by Species’ Common Names and

Ordered by Decreasing Total Air Pollution Benefits per Public Tree

Species Deposit O3 (lb)

Deposit NO2 (lb)

Deposit PM10

(lb)

Deposit SO2 (lb)

Total Deposit.

($)

Avoided NO2 (lb)

Avoided PM10

(lb)

Avoided VOC (lb)

Avoided SO2 (lb)

Total Avoided

($)

BVOC Emission

(lb)

BVOC Emission

($)

Total (lb)

Total ($)

% Total Tree

Number

Avg. $/tree

Silver maple 248.2 42.1 127.4 11.0 $1,354 663.9 97.1 92.7 636.5 $4,152 -140.8 -$528 1778.2 $4,978 5.2 $7.69

Callery pear 50.0 8.6 30.5 2.2 $287 368.6 53.0 50.4 341.5 $2,274 -15.3 -$57 889.6 $2,504 5.4 $3.69

Ash 21.3 3.7 13.0 0.9 $122 151.0 21.6 20.6 138.9 $929 -6.5 -$24 364.5 $1,027 2.6 $3.21

Sweetgum 5.3 0.9 4.0 0.2 $33 75.1 10.8 10.3 69.9 $464 -6.7 -$25 169.8 $472 1.2 $3.04

Honeylocust 40.6 6.7 24.9 1.9 $233 377.9 54.5 51.8 351.5 $2,335 -23.1 -$87 886.7 $2,481 7.2 $2.76

Hedge maple 14.1 2.4 8.3 0.6 $80 96.4 14.0 13.3 90.4 $598 -6.1 -$23 233.4 $655 2.0 $2.66

Maple 47.4 8.1 24.4 2.1 $259 199.4 29.0 27.6 188.9 $1,241 -17.3 -$65 509.7 $1,435 4.4 $2.62

Sugar maple 45.1 7.7 25.9 2.0 $254 271.8 39.6 37.8 258.6 $1,695 -38.1 -$143 650.5 $1,806 5.7 $2.56

Norway maple 38.5 6.6 24.3 1.7 $224 306.5 43.9 41.6 280.9 $1,883 -12.1 -$45 732.0 $2,061 6.9 $2.38

Flowering crabapple 21.8 3.6 11.9 1.0 $121 154.9 22.0 20.9 140.0 $946 -0.1 $0 376.0 $1,067 4.3 $1.98

Red maple 39.7 6.8 22.9 1.8 $224 252.3 36.5 34.8 236.9 $1,565 -15.8 -$59 615.9 $1,730 7.0 $1.97

Linden 10.6 1.8 7.5 0.5 $64 129.8 18.6 17.7 119.7 $799 -12.4 -$46 293.8 $817 4.4 $1.50

Elm 3.0 0.5 2.1 0.1 $18 32.4 4.6 4.4 29.3 $198 -1.1 -$4 75.3 $212 1.1 $1.48

Japanese tree lilac 6.9 1.1 4.3 0.3 $40 68.5 9.7 9.1 60.9 $416 0.0 $0 160.8 $455 2.5 $1.45

Freeman maple 17.0 2.9 16.7 0.7 $115 293.3 42.6 40.5 276.4 $1,822 -33.3 -$125 656.9 $1,813 10.3 $1.41

Northern red oak 24.2 4.2 14.8 1.1 $139 161.5 23.4 22.3 151.5 $1,001 -35.5 -$133 367.4 $1,007 6.6 $1.23

Sawtooth oak 7.5 1.3 5.5 0.3 $46 77.2 11.2 10.6 72.3 $478 -11.6 -$44 174.2 $480 3.3 $1.15

Littleleaf linden 7.7 1.3 5.6 0.3 $47 92.8 13.3 12.7 85.9 $572 -4.9 -$18 214.8 $601 4.9 $0.99

Silver linden 0.3 0.1 0.4 0.0 $3 13.2 1.9 1.8 12.1 $81 -0.6 -$2 29.2 $81 1.4 $0.46

Ginkgo 0.7 0.1 0.4 0.0 $4 5.3 0.8 0.7 4.8 $32 -0.3 -$1 12.6 $35 1.5 $0.19

OTHER STREET TREES 99.2 16.8 56.3 5.1 $558 494.3 71.4 68.0 462.1 $3,061 -57.7 -$216 1215.4 $3,402 12.0 $2.28

CITYWIDE TOTAL 749.3 127.2 431.2 34.0 $4,222 4286.0 619.5 589.6 4009.1 $26,544 -439.3 -$1,647 10406.5 $29,119 100.0 $2.34

Table 10. Annual Aesthetic or Other Benefits of Public Trees by Species

in Delaware, Ohio

Species Total ($) % Total Tree Numbers

% of Total $

Avg. $/tree

Silver maple $44,461 5.2 19.8 $68.72

Callery pear $17,125 5.4 7.6 $25.26

Freeman maple $30,931 10.3 13.8 $24.07

Ash $7,154 2.6 3.2 $22.36

Honeylocust $18,866 7.2 8.4 $20.96

Hedge maple $5,137 2.0 2.3 $20.88

Maple $10,209 4.4 4.5 $18.66

Norway maple $15,727 6.9 7.0 $18.18

Sugar maple $12,093 5.7 5.4 $17.13

Sweetgum $2,273 1.2 1.0 $14.66

Red maple $12,794 7.0 5.7 $14.57

Elm $1,809 1.2 0.8 $12.65

Littleleaf linden $7,634 4.9 3.4 $12.62

Linden $4,417 4.4 2.0 $8.09

Sawtooth oak $2,893 3.3 1.3 $6.95

Northern red oak $5,534 6.6 2.5 $6.74

Flowering crabapple $2,698 4.3 1.2 $5.01

Japanese tree lilac $1,171 2.5 0.5 $3.72

Silver linden $540 1.4 0.2 $3.09

Ginkgo $137 1.5 0.1 $0.75 OTHER STREET TREES $21,322 12.0 9.5 $14.26

CITYWIDE TOTAL $224,927 100.0 100.0 $18.05

16

Table 11. Annual Benefits per Sector and Total Annual Benefits

per Tree by Decreasing Benefits for Delaware Public Trees

Species Energy CO2 Air

Quality Stormwater Aesthetic/Other Total

Silver maple $44.66 $8.13 $7.69 $71.03 $68.72 $200.23

Callery pear $24.73 $2.99 $3.69 $17.21 $25.26 $73.88

Ash $21.66 $2.58 $3.21 $15.24 $22.36 $65.05

Sweetgum $21.86 $2.27 $3.04 $15.02 $14.66 $56.86

Honeylocust $19.10 $2.00 $2.76 $10.94 $20.96 $55.76

Sugar maple $16.95 $2.06 $2.56 $16.79 $17.13 $55.49

Hedge maple $17.66 $1.89 $2.66 $12.02 $20.88 $55.11

Maple $16.18 $1.84 $2.62 $13.04 $18.66 $52.35

Norway maple $16.37 $1.99 $2.38 $11.00 $18.18 $49.92

Freeman maple $10.25 $1.43 $1.41 $10.05 $24.07 $47.21

Red maple $12.93 $1.37 $1.97 $8.82 $14.57 $39.67

Elm $10.60 $1.27 $1.48 $6.45 $12.65 $32.46

Linden $10.88 $1.15 $1.50 $7.68 $8.09 $29.30

Flowering crabapple $13.56 $1.36 $1.98 $5.53 $5.01 $27.44

Littleleaf linden $6.99 $1.02 $0.99 $4.37 $12.62 $25.99

Northern red oak $8.87 $0.91 $1.23 $6.13 $6.74 $23.88

Sawtooth oak $8.39 $0.88 $1.15 $5.03 $6.95 $22.41

Japanese tree lilac $10.48 $1.02 $1.45 $4.00 $3.72 $20.67

Silver linden $3.49 $0.32 $0.46 $1.74 $3.09 $9.11

Ginkgo $1.34 $0.11 $0.19 $0.74 $0.75 $3.15

OTHER STREET TREES $14.89 $1.76 $2.28 $14.18 $14.26 $47.37

17

Table 12 Environmental Benefits from Five Categories for Delaware Trees

Adjusted to Estimated Total

Benefits Total ($) $/tree

Aesthetic/Other $224,927 $18.05

Energy $193,193 $15.50

Stormwater $167,550 $13.44

Air Quality $29,119 $2.34

CO2 $24,276 $1.95

Total Benefits $639,065 $51.27