EH Urb For. Fall 2011 - UC Davis Plants€¦ · fair or better; only 79% strip) • More replacement 23. Sidewalk Damage Sidewalk Damage - Large Trees 85.7 70 80 90 g 61.1 ... BOI

EH Urb For.Fall 2011

Designing for Designing for Longevity

ENH 100Davis, California

Paula Peper, EcologistUrban Ecosystems & Social DynamicsPacific Southwest Research Station Pacific Southwest Research Station,

USDA Forest Service

…early tree planting …early tree planting in the west

3

Imposing Imposing ourselves

on the land

1910 - on G looking north from Fifth Street, Davis, CA

41913 - 6th and E Streets, Davis, CA

Cheyenne WyomingCheyenne, Wyoming

Vegas Vegas Beginningsg g

6

Las Vegas Today

Center for Urban Forest Research

7Eric Condra Photography, Paoli, IN http://www.flickr.com/photos/32838849@N08/4177942149/

Case Study: SacramentoCase Study: Sacramento

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Center for Urban Forest Research 9

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Center for Urban Forest Research 11Photo credit: Alan Grinberg

Gold RushGold Rush

12

h d h lWhy Did They Plant?H lth • Health – swamp reduction

• Flood protectionFlood protection• Shade• Winter windbreaks• Food• Aesthetics

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Sacramento’s “Park Neighborhoods”: Neighborhoods :

What Worked, What Did Not?• Planting space• Spatial relations

• Sacramento’s “streetcar suburbs” p

between houses, infrastructure,

• Trees became drawing point

trees• What happened to

t ti ?

• Major planting 1860s through 90s

trees over time?• Was anything

learned?learned?14





h dWhat and How

• Plane trees and elms

• Planted 20’ apart• Planting strips –

– P. orientalis, occidentalisU glabra procera

g pcame in late 1800s

– U. glabra, procera, americana, thomasii, alata

– 2.5’ to 15’

• lawns/lots

• Palms• Redwoods

• 1938 – trees are 70 years old

• Eucalypts19


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CausesCauses• Improper planting• Improper planting• Improper pruning• Roots cut with street and

sidewalk development• Began systematic removals

35-50 ft spacing (until $$ p g (ran out)

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Trees in Planting Strips(<15 feet)

• Smaller the space, more treesS ll th • Smaller the space, higher mortalityS ll • Smaller space, poorer condition (94% lawn trees in (94% lawn trees in fair or better; only 79% strip)p)

• More replacement23

Sidewalk DamageSidewalk DamageSidewalk Damage - Large Trees

85.7

70

80

90

g 61.1

53.3

40

50

60

ees

Dam

agin

g

33.3

20

30

40

% o

f Tre

0

10

2-4 4-6 6-8 8-10 10-12 18-20Setback Between Tree Center and Sidewalk (ft)

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( )

Our research: Larger space = larger tree + longer life

Center for Urban Forest Research 2525Larger tree = greater benefits for longer period

Factors Affecting Tree Factors Affecting Tree Growth and Longevityg y

Still making some of the same Still making some of the same old mistakes

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Today

27

Today

Coast Redwoods

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Coast Redwoods

Drainage

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l f lCycle of Failure

• Plant trees• They grow upy g p• Bad things happen• We don’t like those trees anymorey• Time passes• Same “bad” trees planted in same places Same bad trees planted in same places

again

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When things go wrong…When things go wrong…

t t th bl32

…trees get the blame

SustainabilitySustainability• Maximize and Maximize and

maintain benefits through time

• Trees may not “belong” but are top mitigators of the harsh environments we environments we create

Arborists and Landscape hArchitects --Site Assessment:

3-Step Approach3 Step Approach• Assess the site above groundg• Assess the site below ground• Select the best tree for that • Select the best tree for that

site (what does the tree need?)need?)

+

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h h lThe Right Place

Aboveground

The RightPlace

g

Belowgrounde o g ou d

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Space for successful trees

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Space for Successful Trees

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S i Species Match Site Match Site

Conditions & R i Requirements at Local Levelat Local Level

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Develop Develop Area

SpecificSpecies Species Profiles

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Local Tree Matrix• Climate adapted• Disease/pest /p

susceptibility• Soil Toleranee• Pruning needs• Branch Strengthg• Root damage• Longevityg y• Availability• BVOC emissionsBVOC emissions• Aesthetic Value 40

Tree Growth in U.S.Tree Growth in U.S.

• Started in 1998• Completed 2010• Goal

– 16 Climate zonesid i h – Provide users with

ability to import a tree inventory and yreceive info on benefits and costs

T th d t • Tree growth data 41

Tree Growth• Over 17,000• 171 species• 171 species• Overlap

– Sweetgum 10– Honeylocust 10– Silver maple 9– Callery pear 9– Green ash 8

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Comparisons and trendsComparisons and trendsSilver Maple

80

90

BIS

• Overlap– Sweetgum 10

40

50

60

70

eigh

t (ft)

BOI

CLT

CYS

FNL

– Honeylocust 10– Silver maple 9

Callery pear 9

10

20

30

40

He FNL

IND

JFK

MOD

– Callery pear 9– Green ash 8

0

10

Years After Planting

MOD

43

Boise

Fort Collins

30-year old green ash

Cheyenne

Green Ash

70

80

Green Ash

67 ft

50

6062 ft

100%

57%52 ft

30

40

Gro

wth

(ft)

45 ft

55%44 ft

10

20

G 45 ft29 ft

00 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80

Years

45

Cheyenne Boise Ft. Collins

Benefits ($) from 100 Green Benefits ($) from 100 Green Ash over 40 Years

City Energy CO2Air

QualityStorm‐ water

Total Services

Ft C lli 86 18 14 83 201Ft. Collins 86 18 14 83 201Boise 63 12 8 56 139Cheyenne 30 6 3 28 67Cheyenne 30 6 3 28 67

units in $1,000s

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Cheyenne Climate– 4th windiest city– Highest incidence of

h il thailstorms– 14.4 in precipitation– Low humidity and higher – Low humidity and higher

altitude (6138 ft)– Alkaline soils– Low water-holding capacity

Wyoming: Not for lightweights

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LiquidambarLiquidambarSweetgum in three California cities at age 40

Pruning Effects on $$

70

Sweetgum

50

60 60 ft$25$100k

30

40

50

th (f

t)

72%

$25

20

30

Gro

wt

$18 $72k

0

10

0 5 10 15 20 25 30 35 40 45 50 55 60 65

50

0 5 10 15 20 25 30 35 40 45 50 55 60 65Years

MOD CLM

Pruning Effect on Benefits ( T )(100 Trees over 40 Years)

90Siberian Elm

70

80

90

40

50

60

wth

(ft)

74 ft

51 ft

f

52 ft

36 ft

$177k

$139k

10

20

30

Gro

w

40 ft

43 ft

21 ft31 ft

36 ft

24 ft$97k

00 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80

Years

51

Cheyenne Boise San Fran

Tree FoliageTree Foliage• Intercept air pollution and

particulates• Intercept rainfallp• Process carbon

dioxidedioxide• Shade –heat

island and energygy

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Poor pruning• Increases maintenance cost• Turns large trees into small• Turns large trees into small• Decrease life expectancy

Largeg$213/tree

Small53

Small$44/tree

Don’t Generalize --Localize Know local conditions and how

trees respond to those trees respond to those conditions

Put the right tree in the right Put the right tree in the right city….

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Communicate

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In most In most communities

the links are not 56connected

In most In most communities

We seldom 57

We seldom communicate

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C i tCommunicateto Build Longevity into Life to Build Longevity into Life

Cycle

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NurseriesNurseries

• Planting practicesg p– Containers– Root issues– Species offerings– Cultivars

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Retailers• Stop holding stock• Expand selectionp• Reduce invasives• Promote the

benefits at less cost

Center for Urban Forest Research

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Plan Space CorrectlyR t l f 2 id ti l t tRecent plans for 2-way residential street

Actual Two-way Streets


Enough Space for Healthy Growth

12 ft

Red mapleSh d d t • Shaded out one side

• Imbalance• Imbalance• Top damaged by

falling ash branchfalling ash branch

Think about the Tree’s Needs

Overplanted—soil and water issues

Oak & ZelkovaBeneath Ash

Improper placement

lPlant More Trees

…with forethought

Plant Larger Growing Trees

Photo courtesy of David Roberts

Smaller Space? p

Plant smaller tree for fewer costs 70+ more benefits

Maintain Existing Trees

Photo courtesy of David Roberts

Plan Ahead & Educate

To Optimize Tree Benefits and Plan for Sustainability

• Trees become integral component of infrastructureco po e t o ast uctu e

• Masterplanning and design i t processes incorporate

appropriate space for trees from outset

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SustainabilitySustainability• Frequent interdepartmental

communication understand and communication – understand and educate each otherU d d l l • Understand local tree performance/needs/limitations

• Plant for quality not quantity• Prune to ANSI standards – with

benefits in mind• Educate educate educateEducate, educate, educate

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U b f t Urban forest sustainabilityy

i l l75

involves many players

Bottom Line: Trees are like puppiespuppies

Documents

EH Urb For. Fall 2011 - UC Davis Plants€¦ · fair or better; only 79% strip) • More replacement 23. Sidewalk Damage Sidewalk Damage - Large Trees 85.7 70 80 90 g 61.1 ... BOI