HomeMy WebLinkAboutRes 1906 - EXHIBIT A: Green Tukwila 20-Year Stewardship PlanFollowing is
Green Tukwila 20 -Year Stewardship Plan
Adopted by Res 1906
Green Tukwila 20 -Year
Stewardship Plan
GREEN TUKWILA
PARTNERSHIP
ACKNOWLEDGMENTS
The Green City Partnerships program started in 2004, comprises a network of
.,, public- private ventures between Forterra, local government agencies, businesses,
GREEN TUKWI LA organizations, and citizens. This effort set the stage for engaging the public in
PARTNEIl$I. P
ongoing stewardship of urban forests and natural areas and was expanded into cities
throughout the Puget Sound Region with the formation of new partnerships. We
developed the Green Tukwila Partnership based on these efforts, creating a plan to
address the needs of the Tukwila community. This important work was funded, in
part, by a generous grant from Boeing's Healthy Communities Initiative.
TUK 'ILA
PARKS & RECREATION
_C ,_ALT
FORT&RRA
AFM
City of Tukwila Elected Officials
Mayor: Allen Ekberg
City Council: Joe Duffle, Council President
Dennis Robertson Vema Seal
Kathy Hougardy De'Sean Quinn
Kate Kruller Thomas McLeod
Park Commission: Mike Martin, Chair
Don Scanlon
Heidi Watters
Sean Albert
Matt Mega
Tukwila Staff Advisory Group
Robert Eaton, Parks and Recreation Manager
Carol Lumb, Senior Planner, Department of Community Development
Andrea Cummins, Urban Environmentalist, Department of Community Development
Mike Perfetti, Habitat Project Manager, Public Works Department
Forterra
Norah Kates, Green Cities Project Manager
Kimberly Frappier, Restoration Ecologist
Matt Mega, Green Cities Project Manager
Joanna Nelson de Flores, Green Cities Director
Nicole Marcotte, Green Cities Project Associate
Christopher Walter, GIS Director
American Forestry Management, Inc.
Data Collection
Jesse Saunders, Inventory Forester
Ted Hitzroth, GIS Manager
Green Tukwila 20 -Year Stewardship Plan 1
llustrations
Andrea Mojzak
Photography
Nicole Marcotte
Photography by McRob (www.mcrobphoto.com)
Billy Hustace (hustacephotogrpahy.com)
Nick Krittawat
Uncredited photos were taken by Forterra or Tukwila Parks and Recreation
Editing
Diane Sepanski
2
TABLE OF CONTENTS
Acknowledgements 1
Executive Summary 6
I. Introduction 8
The Need for a Green Tukwila Partnership 9
Investing in Tukwila's Urban Forest: Public Health, Economic and Ecosystem Benefits 9
II. The Challenge: Threatened Forests and Natural Areas 15
Challenges and Threats to Sustainability 16
Fragmentation 16
Declining Habitat Quality 16
Invasive Species: Plants 17
Invasive Species: Insects 18
Native Vegetation Struggling to Regenerate 19
Illegal Activity 19
Climate Change 19
Resource Limitations on Forest and Natural Area Restoration and Maintenance 20
III. Meeting the Challenge 21
The Mission and Vision 21
Outcomes 22
Goals 22
Partnership Roles and Responsibilities 23
City of Tukwila 23
Seattle City Light 24
King County Parks 24
Tukwila School Distrcit 24
Highline School District 24
Washington Department of Transportation 24
Washington Department of Natural Resources 24
Nonprofit Organizations 25
Volunteers and the Community at Large 26
Commercial and Nonprofit Field Crews 26
Funders, Donors and Sponsors 26
Private Landowners 27
IV. Forest and Natural Areas Assessment 29
Methods 29
Tree -iage and Forest Landscape Assessment Tool (FLAT) 29
Tree -iage Categoroes 30
Results 33
Tree -iage Matrix 33
Overstory Species 34
Regenerating Overstory Species 34
Native Overstory Species 34
Green Tukwila 20 -Year Stewardship Plan 3
Native Understory Species 34
Invasive Species 34
Slope 35
V. Moving Forward — The Next 20 Years 36
Field 36
Field Objective 1: Prioritize Parks and Natureal Open Space Sites 37
Field Objective 2: Prioritize Restoration Work Zones Within Sites 37
Field Objective 3: Identify Areas that Require Professinal Crew and Staff Support 37
Field Objective 4: Implement BMP's in Restoration and Stewardship on all Project Sites 38
Best Management Practices 38
The Four -Phase Approach to Restoration Fieldwork 38
Application to the Tree -age Categories 41
Community 46
Community Objective 1: Promote Positive Engagement with Parks and Natural Open Space 46
Community Objective 2: Prioritize Safety and Use Partnership Efforts to Contribute to Public Safety 46
Community Objective 3: Develop and Implement a Community Outreach and Engagement Plan to Equitably
Serve Tukwila's Diverse Residential Population 46
Community Objective 4: Work With Local Businesses to Encourage Corporate Support for th ePartnership 46
Community Objective 5: Seek Opportuntiies to Engage Youth and Provide Education 48
Community Objective 6: Build a Steward Program to Promote and Support Community Leadership 48
Community Objective 7: Appreciate Volunteers and Publicly Celebrate Partnership Success 49
Community Objective 8: Engage and Educate Residents and Private Landowners 49
Resources 50
Estimating Program Costs 50
Resource Objective 1: Continue Current City Funding and Build Capacity for Future Growth 55
Resource Objective 2: Leverage City Funds Through Partnerships and Develop Long -Term Funding to Support
the Work 55
Resource Objective 3: Provide Sufficient Staff and Resources to Support Fieldwork, Volunteer Outreach and
Management, Community Engagement and Program Administration 55
Resource Objective 4: Coordinate Efforts by Partner Staff and Volunteers to Maximize Joint Success and
Share Resource 56
Resource Objective 5: Deploy Skilled Field Crews as Appropriate, Prioritizing Training Crews and Job- Skills-
Development Programs Available to Tukwila Residents 57
Resource Objective 6: Increase Volunteer Engagement to Leverage Support From Community 57
Resource Objective 7: Support Local Businesses 58
VI. Adaptive Management 59
Measuring Success 60
Program Evaluation 60
Resource Distribution 61
Reporting and Knowledge Sharing 61
VII. References and Further Reading 63
VIII. Appendices 66
Appendix A: Neighborhood Tree -iage Maps 66
Appendix B: Forest Landscape Assessment Tool (FLAT) Flow Chart for Habitat Composition 74
4
Appendix C. Management Unit Acres per Tree -iage Acre per Park 75
Appendix D: Dominant Overstory Species by Management Unit Acres 77
Appendix E: Understory Species Dominance by Management Unit Acres 78
Appendix F. Invasive Species Occurrences by Management Unit Acres 79
Appendix G: Public Input 80
Appendix H: Short and Long -Term Strategic Plan and Benchmarks 87
Appendix I: Glossary 111
LIST OF FIGURES
Figure 1: Green Tukwila Partnership Site Map 14
Figure 2: A Projection of Forest Decline 17
Figure 3: A Projection of Forest Restored 21
Figure 4: Tree -iage Legend 30
Figure 5: Distribution of Management Acres Across Tree -iage Categories 30
Figure 6: Canopy Composition 31
Figure 7: Invasive Cover 31
Figure 8: Distribution of Overstory Tree Species by Management Unit Acres 31
Figure 9: Distribution of Top Five Regenerating Overstory Species by Management Unit Acres 32
Figure 10: Distribution of Top Five Regenerating Overstory Species by Management Unit Acres 32
Figure 11: Distribution of Most Common Invasive Species by Management Unit Acres 33
Figure 12. Decision tree for prioritizing restoration sites 36
Figure 13: Restoration Strategies and Tree -iage Categories 39
Figure 14: 20 -Year Projections of Program Costs and Volunteer Match Value 52
Figure 15. Adaptive Framework Cycle 59
LIST OF TABLES
Table 1: Quantity and Value of Air- Quality Services Provided by Tukwila's Urban Forest 11
Table 2: Ecological and Public Health Benefits of Urban Forest and Natural Areas 12
Table 3: Green Tukwila Partnership Management Structure 27
Table 4: Land Ownership (acres) 50
Table 5: Average Restoration Cost per Acr by Tree -iage 51
Table 6: Parks and Recreation Land Cost Summary 52
Table 7 School District Land and ROW Cost Summay 53
Table 8: King County, Washington State Dept of Transportation, Seattle City Light and Private Lands 53
Table 9: Other Jointly Managed Lands Cost Summary 54
Table 10: All lands Cost Summary 54
Green Tukwila 20 -Year Stewardship Plan 5
EXECUTIVE SUMMARY
In 2015, the City of Tukwila and Forterra formed a partner-
ship to evaluate the condition of Tukwila's forested parks and
natural areas, and develop a plan to help ensure that Tukwila's
vision of a sustainable, healthy system of connected parks and
natural areas becomes a reality. Tukwila is the eighth Green
City, and joins Seattle, Tacoma, Puyallup, Kent, Redmond,
Kirkland, Snoqualmie and Everett. Together, Green Cities
in the Puget Sound Region located in three counties (King,
Pierce and Snohomish), represent a population of more than
3 million people
with a goal to re-
store and maintain
9,000 acres of
land. The Green
Tukwila Partner-
ship will join this
robust network
of resources and
expertise, help-
ing to ensure a
livable and healthy
region.
The City of Tuk-
wila undertook
the creation of this Green Tukwila 20 -Year Stewardship Plan
to provide a strategy for the active restoration and manage-
ment of 138 acres of land. Restoring these lands is considered
critical to the health and welfare of the citizens of Tukwila.
Although this is an ambitious task, it is important for the
health of natural areas and the City of Tukwila, and it is
only possible with the help of an engaged community and
volunteer leaders. Tukwila's natural areas face the same kinds
of pressures and problems as many urban forests, including
fragmentation, an invasive - dominated understory that inhib-
its native species from regenerating, a declining tree canopy,
and resource limitations on natural -area management and
restoration. These pressures diminish the benefits provided
by these valuable lands, such as reduced stormwater runoff,
improved water and air quality, attractive communities and
stronger property values, greenhouse gas reduction, habitat
for native wildlife, and improved quality of life.
The Green Tukwila Partnership's vision is to have healthy
forested urban parks supported by an aware and engaged
community in which individuals, neighborhoods, nonprof-
its, businesses, and city government all working together to
protect and maintain their valuable public resources. The
envisioned management program will be dedicated to restor-
ing and maintaining forested parks and natural areas while
fostering appreciation and understanding of the long -term
benefits that urban forests provide to the City of Tukwila.
The intent of this plan is to articulate measurable goals and
objectives, develop strategies for achieving these goals and
establish benchmarks for evaluating success. This plan will
ensure the public
investment in these
lands is effectively and
efficiently allocated
across natural areas in
Tukwila and that the
full implementation of
this plan over the 20-
year timeframe will be
achieved.
6
Photo by Nick Krittawat
The Plan Objectives
are:
1. All 138 acres of
forested parks and
natural areas
within the Green Tukwila Partnership will be enrolled
in active restoration and maintenance by 2036.
2. An active management program will be in place and
will be implemented beyond 2036 to ensure lands
in active restoration remain ecologically healthy and
provide the numerous ecosystem benefits to the City
of Tukwila.
3. A Forest Steward program will be implemented and
utilized to engage volunteers to lead restoration efforts
of those areas safe and appropriate for volunteer access.
4. A successful volunteer program that engages a diverse
community of individuals, families, schools, businesses
and non - profits will be in place.
5. Sustainable funding and staff resources to accomplish
long -term restoration and management objectives will
be secured.
6. A monitoring and adaptive management program will
be created and implemented to ensure all lands within
Phase 4, long -term maintenance are monitored on a
three year rotating basis
To accomplish the goals of this plan an analysis of the 138
acres of land was conducted. The results of the data analysis
demonstrate that two significant factors will influence the
restoration of forested parks and natural areas in both pri-
oritization and timing. The first is that the majority of lands
(90 %) are impacted by invasive vegetation. Sites with a high
degree of invasive cover will require multiple treatments over
the course of many years. This will extend the length of time
needed before these sites can enter into Phase 4, the long-
term maintenance phase. While some sites do have Douglas -
fir and western redcedar regeneration, the dominate forest re-
generation is black cottonwood, bigleaf maple and red alder.
This is significant because it provides an indication of how
much planting will be required to restore sites to a healthy
condition. Sites with little to no conifer regeneration will
require more tree plantings. Sites with older deciduous trees
will also need to be monitored for hazard tree conditions and
may necessitate expensive tree removal on some sites. Togeth-
er a site with little natural tree regeneration and high invasive
vegetation cover will require extensive restoration, including
significant invasive plant removal and installation of native
plantings, extending the restoration timeline.
Based on the condition assessment results, this plan establish-
es a method of prioritizing habitat restoration activities and
provides a four phase restoration approach. The four phase
approach to restoration starts with invasive plant removal,
initial planting of native species, a period of plant establish-
ment and finally long -term monitoring and care. Prioritiza-
tion will occur based on site conditions, community support,
habitat value, geographic distribution and available resources
to support restoration.
A cost analysis was conducted for the 20 -year timeframe and
determined that the total cost will be $5.73 million dollars
(2016 dollars) to enroll all 138 acres into active restoration.
The cost analysis was also refined to provide an estimate to
enroll the 88 acres of land owned and managed by the City
of Tukwila Parks and Recreation Department into active
restoraiton. This estimate was $3.47 million. The total cost
for the Green Tukwila Partnership is a significant invest-
ment, but one that will ensutre the long -term sustainability
of Tukwila's forested parks and natural areas. This cost also
includes volunteer and skilled professional crew coordination
and management. Volunteers help ensure long -term success
and community ownership. Working side by side with city
staff, volunteers are forecasted to leverage up to an additional
$2 million in value for the Partnership during the course of
the program.
Successful completion of this plan will result in a system
of healthy, functioning forested parkland and natural areas
for improved ecosystem benefits, such as clean air, climate
change mitigation and human mental health.
Green Tukwila 20 -Year Stewardship Plan 7
(.INTRODUCTION
Forests and natural open spaces play a vital role in the
environmental, economic, and public health of our cities.
Tukwila's parks, trails and open spaces are an invaluable asset
for the city and the people who live, work, and play here.
When taken care of properly, nature close at hand can make
Tukwila's neighborhoods active and vibrant, and help define
the community. Tukwila's urban forest, natural shorelines,
streams, and wetlands provide numerous services that
benefit all areas of the city. They absorb stormwater runoff
and stabilize shorelines and steep slopes, thereby reducing
flooding and erosion. The vegetation and soils in these forests
filter polluted runoff, providing clean water. Air quality is
improved through the capture of particulates intercepted by
the tree canopy (McPherson), and by providing shade on
the hottest days, which has an effect on many temperature -
dependent and /or ozone - forming chemicals (Nowak 2002).
The cooling effect created through a combination of shade
and altered patterns of air movement are greatest within
a forested area, but also extend to developed areas outside
of nearby parks. Cooler temperatures make urban areas
more comfortable on hot days, but can also have significant
impacts on human health, as heat waves cause hundreds of
deaths in the United States annually. Vulnerable populations
8
such as the young, elderly, and sick are especially at risk.
Natural open spaces also enhance the livability of our
neighborhoods, make our city more beautiful, and provide
habitat for local wildlife.
Historically, development was the largest threat to natural
areas in urban and suburban centers in the Puget Sound
region. Public agencies and land trusts have worked to reduce
this threat by purchasing and conserving natural areas —
land conservation is an important first step in preserving
the region's natural resources. Many properties were origi-
nally forests set aside to allow nature to take its course with
the goal of minimizing human impacts. We have learned,
however, that urban environments face unique pressures that
render passive management inadequate to maintain a high
quality of environmental health. Invasive species, litter, pol-
lution, changes in surrounding land use, and parcel fragmen-
tation reduce the forest's ability to thrive within cities and
suburban areas. Urban forest areas are disappearing, and with
them go the critical services they provide. Lack of engage-
ment by residents combined with lack of upkeep can lead to
public perception of these areas as neglected, uninviting, and
dangerous, which is sometimes true.
The dominance of nonnative plant species, such as English
ivy, Himalayan and evergreen blackberry, reed canary grass,
and Scotch broom, is reported to be a major cause of bio-
diversity loss and ecosystem degradation in urban forests
What Is Active Management?
Tukwila's parks, trails and open spaces have a variety of needs, some of them specific to urban
areas. Meeting these needs and caring for these parks includes removing invasive plants,
planting native plants, watering, mulching, stabilizing stream banks, removing garbage or yard
waste, maintaining trails, or visiting to check for new problems that arise. We refer to these
activities as "active management;' which acknowledges that caring for urban natural areas
requires a dynamic, hands -on effort in the field to counteract the pressures they face.
(Pimentel et al. 2000; Soule 1991). These invasive weeds
lack natural population control (e.g., predators, diseases) and
are capable of rapid reproduction; they can quickly blanket
the understory and prevent native plants from reseeding
(Boersma et al. 2006). Invasive vines such as English ivy and
clematis climb into treetops, where they can block light from
reaching a tree's leaves, and their heavy weight can topple
trees. Without native plants in the understory, habitat and
food supply for native wildlife are greatly reduced, and the
next generation of native tree canopy is lost. This problem
is exacerbated by the fact that a significant portion of for-
est canopy in the Puget Sound region is now composed of
relatively short - lived, mature bigleaf maples and red alders
coming to the end of their life spans. As these trees succumb
to age, new seedlings are not present to replace them, result-
ing in a loss of forests over time.
Tukwila's urban forests can significantly benefit from inter-
vention to help reverse this trend and prevent major loss of
habitat and ecological functions. The City of Tukwila and
Forterra partnered to develop a coordinated restoration and
stewardship program called the Green Tukwila Partnership.
The Partnership developed this 20 -year Stewardship Plan to
comprehensively assess the conditions of Tukwila's forested
parkland and natural open space under the jurisdiction of the
city and several partner land- owning agencies. The plan also
assesses agency coordination and capacity, promotes com-
munity participation, and establishes the long -term planning
needed to support the Partnership's goals and vision.
THE NEED FOR A GREEN TUKWILA
PARTNERSHIP
With continued population growth anticipated throughout
the Puget Sound region, Tukwila's residential and business
density will be higher. One of the challenges facing the city
is how to balance this growth while maintaining a strong
economy and exceptional quality of life. For example, since
increasing high - density housing, including condominiums
and multifamily developments, often results in less personal
access to open space and the natural environment, it is im-
portant to protect and enhance Tukwila's parks and natural
areas.
Additionally, urban developments such as condominiums,
townhouses, and office parks are considered more desirable
when they are conveniently located and accessible by bike or
on foot, near transit, parks, and natural areas (Tyrvainen and
Miettinen 2000). This measurable value is due to the fact
that green space is an important element of livable, attractive
communities. Parks, trails, and natural areas give people who
live in cities recreational opportunities and a connection to
nature that can help sustain a vibrant urban life. Trees and
green space are also associated with a variety of measurable
public health benefits by providing people with access to
nature and the amenities needed for exercise, both of which
have links to stress reduction and physical wellness (see Table
2).
In 2005, Forterra launched the Cascade Agenda, a 100 -year
vision for conservation and economic growth in the Pacific
Northwest, with a central focus on building livable urban
communities. Recognizing that access to healthy parks is a
How Large is 138 Acres?
At 138 acres, Tukwila's forested parks
and natural areas, combined together,
represent and area that is 73 times the
size of a regulation soccer field or 2.5
times the size of Fort Dent.
Soccer Field x 73
a)
Fort Dent
Park
Fort
Dent x 2.5
Green Tukwila 20 -Year Stewardship Plan
9
key component to a livable city, the City of Tukwila is com-
mitted to providing access and care to their valuable natural
areas. Combined, Tukwila's parks and natural open space
make up 138 acres, roughly 2% of the City's total land area.
The Partnership aims to bring 138 acres of Tukwilas forested
parkland into active management over the next 20 years.
Although this is an ambitious task, it is crucial for the health
of the city's urban forests — and the city itself. This will only
be possible with the help of an engaged and dedicated com-
munity that has an ownership stake in the Green Tukwila
Partnership's success.
Similar Green City Partnerships have already seen success
in Seattle, Tacoma, Kirkland, Redmond, Kent, Everett, and
Puyallup. Together, these partnerships are establishing one of
the largest urban- forest restoration programs in the nation.
INVESTING IN TUKWILA'S PARKS,
TRAILS AND OPEN SPACE: PUBLIC
HEALTH, ECONOMIC, AND
ECOSYSTEM BENEFITS
The benefits of caring for Tukwila's urban forests affect many
aspects of the community. Research indicates that urban for-
ests give people a higher quality of life (Dwyer et al. 1992),
provide ecosystem functions, and create opportunities to
improve physical and mental health, and enjoy nature close
at hand. They help keep the air and water cleaner, provide
habitat for native wildlife, and make communities more liv-
able and beautiful.
The Puget Sound region's forests provide measurable, valu-
able services that affect us every day. In 1998, American For-
ests, a nonprofit citizens' conservation organization, analyzed
our urban forests. Its study revealed that these trees removed
38,990 tons of air pollution — a service that was then valued
at $166.5 million. The study also showed that the trees cre-
ated a 2.9 billion- cubic -foot reduction in runoff, a service
valued at $5.9 billion (American Forests 1998). Were these
forests to be lost, these dollar values become the costs associ-
ated with building new infrastructure to carry out equivalent
functions.
A city with abundant and healthy vegetation enjoys signifi-
cantly higher air quality. Conifers, specifically, can remove 50
pounds of particulate pollutants from the air per year (Dwyer
10
et al. 1992), which is correlated in studies with a reduced
incidence of asthma in children and other related respiratory
health issues in people of all ages (Logvasi et al. 2008).
Urban forests also help combat climate change and the effects
of air pollution. Trees, as they grow, capture carbon diox-
ide through the process of photosynthesis and help remove
soot and other pollutants through their leaves and branches.
They store the carbon from the absorbed carbon dioxide in
the woody mass of their branches and trunks, and release
oxygen into the air. It is estimated that Washington State's
urban trees are responsible for the sequestration of more than
500,000 tons of carbon per year (Nowak and Crane 2001).
Each acre of healthy, mature Western Washington forest
could be responsible for the storage of more than 300 tons of
carbon, which translates to the removal of more than 1,100
tons of carbon dioxide from the atmosphere (Smithwick et
al. 2002). For example, the average passenger vehicle emits
4.7 tons of carbon dioxide per year (EPA 2014). This means
each acre of healthy forest removes carbon dioxide emissions
for approximately 234 vehicles.
Trees in an urban setting combat the "urban heat - island ef-
fect" caused by paved surfaces absorbing and radiating heat
from the sun. Trees produce shade, reflect sunlight well above
the pavement, and convert sunlight through photosynthesis.
Urban forests also create microclimates that move air and
further cool their surroundings. They have been shown to
significantly lower ambient temperatures, making hot days
more comfortable and reducing energy consumption needed
for artificial cooling (Nowak and Crane 2001). A single
25 -foot tree reduces a typical residence's annual heating and
cooling costs by an average of 8 % -12% (University of Wash-
ington Center for Urban Horticulture 1998).
While invasive plants such as ivy and blackberry also carry
out photosynthesis to sequester carbon and create oxygen,
they are shorter lived and contain less biomass than mature
conifers. This makes them less effective at removing carbon
dioxide from the atmosphere and storing it. Additionally,
they often do not supply adequate habitat for local native
wildlife and are much less effective at providing other ecosys-
tem functions than healthy native Northwest forest commu-
nities. For example, while some birds will nest in blackberry
bushes, it takes a variety of native plants to provide nesting
opportunities for all our local bird species (Marzluff 2000).
The monocultures that invasive plants typically create do not
foster the diverse assemblage of interrelating native species
that keep natural areas healthy and stable.
In 2012, Davey Resource Group estimated the benefit of
trees to the City of Tukwila as part of a tree - canopy assess-
ment. Table 1 shows the approximate quantity of pollutants
intercepted and the value of that service to the city. These
values were generated using i -Tree VUE and are referenced in
the City of Tukwila Comprehensive Plan 2015.
More research is still needed to quantify the economic and
ecosystem functions provided by urban forests specific to the
City of Tukwila. Additionally, drawing from the wide body
of knowledge and related studies outlined here, we know
that the cost of doing nothing to maintain the health of our
public natural areas could be high and have negative effects
on the city's environmental, economic, and public health.
As development throughout the region continues at a rapid
pace, our remaining parks and natural areas are more impor-
tant than ever.
Pollution Source
Stored carbon
Approximate
Benefit
71,000 tons
Approximate
Value
$1.4 million
Sequestered carbon
2,300 tons /year
$48,000
Carbon monoxide
4.3 tons /year
$4,000
Nitrogen dioxide
10 tons /year
$89,000
Ozone
4.3 tons /year
$240,000
Sulfur dioxide
8.5 tons /year
$18,000
Particulate matter
15.7 tons /year
$94,000
Yearly benefit
$1.9 million
Table 1. Quantity and value of air - quality services provided byTukwila's urban forest
Green Tukwila 20 -Year Stewardship Plan 11
Table 2. Ecological and public health benefits of urban forests and natural areas
REDUCE 'ERC ,1
IMPRENE AIR
QiJALI I ,
REDUCE ENERGY USE
& COMBAT CLIMATE
CHANGE
BOOST LOCAL &
RE I NAL ECONO i
12
Tree canopies reduce the rate at which rain falls to the earth. Water enters the
ground more slowly under trees and is better absorbed and filtered into ground-
water than when it runs off paved and nonporous surfaces. Since conifers and
other evergreen plants grow year- round, more water moves up from the ground,
through plant tissues, and into the atmosphere as water vapor. Urban forests can
reduce annual stormwater runoff by 2%-7%, and a mature ta-ee can store 50-100
gallons of water during large storms (Fazio 2012). Green streets, rain barrels, and
tree planting are estimated to be 3 -6 times more effective in managing stormwater
per $1,000 invested than conventional methods (Foster et al. 2011)
Plant roots absorb water, much of which is full of pollutants in an urban environment,
Some pollutants are filtered and transforrned by bacteria and other microorganisms
in the soil (Prince George's County 2007); others are transformed by plants through
metabolism or trapped in woody tissues and released when a tree decomposes.
Forested buffers around streams have been shown to reduce sediment and nutrient
pollution levels (Osborne and Kovacic 1993).
As the tree canopy shows the speed of rain falling on the earth, rainwater
has less energy to displace soil particles. Soils under a canopy and the
thick layer of leaf litter are protected from the erosive energy of rainwater
(?Ciao et al. 1998).
Plant leaves absorb carbon dioxide and produce oxygen through photosyn-
thesis. The surfaces of leaves trap airborne dust and soot (McPherson et al.
1994), removing millions of pounds of air pollutants annually from the air in
a city (American Forests 2001).
Native wildlife has unique requirements for food and shelter. Although rac-
coons and craws adapt well to urban environments, many native species. do
not, They require a variety of plants and multiple layers of canopy to forage
and nest. Healthy urban forests under restoration have been demonstrated to
increase species diversity (Ruiz -Jaen and Aide 2006).
A 25-foot tree reduces annual heating and cooling costs of a typical residence
by an average of 8% -129! (University of Washington 1998). Trees absorb carbon
dioxide and store the carbon in woody tissues reducing the amount of carbon
dioxide in the atmosphere. Urban forests have the capacity to lower energy
consumption in urban environments by lowering ambient temperatures and to
create microclimates conducive to air movement. Lowering energy consurnp-
tion reduces electricity use and the amount of carbon dioxide emitted into the
atmosphere from power plants (Nowak and Crane 2001). Each year, an are of
trees absorbs the amount of carbon produced by driving a car for 26,000 miles
(Nowak et al, 2002).
Urban forestry supports job creation and retention, resulting in added individual
income and increased local, state, and federal taxes (CalFire 2011). Homes that
bonder u,bai forests may be valued at up to 5% more than comparable homes
farther fnorn parks (fyrvainen and Mier-tine( 2000), and street trees add value to
homes as well (Donovan and Butry 2010). Forested parklands provide residential
properties with an adjacent natural area for walking and passive recreation activi-
ties such as bird-watching.
Ecological and public health benefits of urban forests and natural areas continued
MUNI' e:UILDING
MAKE COMMUNITIES
MORE ATTRACTIVE
‘11
11! ;WM
Tree •canopies dampen sound by intercepting sound waves (Herrington
1974). Noise buffers composed of trees and shrubs can reduce 5O% of noise
detectable by the human ear (USDA 1998), including high- frequency noise,
which is most distressing to people (McPherson et al. 2001),
Physical features, particularly nature, play an important role in creating vital
neighborhood spaces (Sullivan et al. 2004)_ Urban greenspaces and parks
provide a gathering place for people of different backgrounds to connect
with each other. Strong community relationships are built from exchanging
information and working together to achieve common goals (e.g_, open -space
improvements). Residents who are more attached to their community have
higher levels of social cohesion and social control, less fear of crime, and display
more signs of physical revitalization of the neighborhood (Brown et al_ 2003).
Vegetation provides visual relief from the built environment. Trees and stretches
of parkland can soften the angular edges of buildings, while the natural tones
of bark and foliage are easy on the eyes. Trees are known to be the most
important factor in influencing the perception of a community's aesthetic value
(Schroeder 1989)_ Trees and natural landscapes are associated with reduced
aggression and violence (IKuc+ and Sullivan 2001), graffiti, vandalism, and
littering (Brunson 1999).
Physical exercise and activity has been shown to reduce the risk of
hypertension, coronary heart disease, stroke, diabetes, and breast and colon
cancer (V+orld Health Organization 2010). People who use parks and open
spaces are three times more likely to achieve recommended levels of physical
activity than nonusers (Giles -Corti et al. 2005). People in communities with high
levels of greenery or greenspace are more likely to be physically active, and
less likely to be overweight or obese (Maas et al. 2006 and Elleway et al, 2005).
Physical activity has also been linked to decreases in symptoms of stress and
depression (U.S. Dept. of Health 1999). The opportunities to exercise provided
by trails through forested parks and natural areas is therefore relevant to
the treatment of these mental health ailments. Even basic mental function is
improved, as the experience of nature helps restore the mind after the mental
fatigue of work or studies, improving productivity and creativity (Kaplan 1995
and Hartig et al. 1991)_
Experience with nature helps children to develop cognitively, emotionally, and be-
haviorally by connecting them to environments that encourage imagination, cogni-
tive and intellectual development, and social relationships (Isenberg and Quisen-
berry 2002 and Heer agen and ( iaris 2002)_ Green settings and green play areas
also decrease the severity of attention deficit in children (Taylor et al. 2001).
Volunteer stewards of all ages who regularly remove invasive species, plant trees,
and perform other stewardship activities are likely to gain health benefits from
physical exertion_ In one hour, a 150-lb persori can bum 340 calories from digging,
gardening, and mulching, 306 calories from planting trees, and 292 calories from
raking leaves (+,uw'iw calorie- count.com).
Green Tukwila 20 -Year Stewardship Plan 13
North
Wind's
Cecil Mosses Weir
Memorial Park
Chinook Wind
O lwaimkh Hill
" Dfish Hill Preserve
Ryas Hilt fwam
,_ Ryan Creek
A I lentown
Fire Station
n7! Duwarnish Park
Daswarnish Gardens
S 115th St Riverbank
42nd Ave 51
5 115th St
Riverbank
S. 125th St Site
Riverton
Creek
TPB & S 134th S
Codiga
1 Park
• U1J 4v3lflifl7. —'*.
Restoration Challenge 4-
gli
Pamela Drive Site
Foster Point Lookout Park
Riverton
Park MP
Southgate
Cascade View Park
Elementary
School
Riverton
Mini
Park
57th Ave 5 Mimi Park
Memoorial
Faster HEgh School and Park
Showalter Middle School
CascadeYiew Community Park/
Tukwila Pool MPD
Foster
Fire Station
S. 140th St. R ^I
Riverbank Parcels
tiacadam
Wetlands
Winter Carden ik
Macadamxd5
Site •l,
Tukwila HItI
Re serwolr
Thorndyke E lem entary School
G1ltiam Creek
Detention
Pond
City Hall WTOkwila Park
Campos
Crystal Springs
Park
laCrestview
Park
interurban
1-1111 Site
a l
59tAve S
Trail
Hazelnut Park
& Fire Station 52
- Trail t
Tukw Ra roll l
Elem-entary
School
Tukwila
Hail Site Trail 4
Fort Dent
Business
Loop
Trail Junction;
Green River
and Interurban
i
14
FI1Ff rF 01,
16 rir ,711.
Figure 1. Green Tukwila Partnership site map
Tukwil▪ a
Parkway
Site
Nelsen
Site
Christenson Rd
Site
Bicentennial Park"
Strander
ROW
Tukwila Pond
Park
P-I
Pond
Yost
VaiI *y
Riverbank
II. THE CHALLENGE: THREATENED
FORESTS AND NATURAL AREAS
TUKWILA'S PARKS, TRAILS AND OPEN
SPACES
The City of Tukwila is located within the Green - Duwamish
River Watershed Water Resource Inventory Area 9, (WRIA
9), split roughly in half between the Duwamish Estuary
Subwatershed in the north and the Lower Green River
Subwatershed in the south. Land use in the city is a mix of
commercial, industrial, and low- and high- density residen-
tial. Weaving through this mosaic is 138 acres of forests,
wetlands, streams, shorelines, and buffers, managed by the
agencies that make up the Green Tukwila Partnership: the
City of Tukwila, along with Seattle City Light, Washington
State Department of Transportation, King County Parks,
Tukwila and Highline School Districts, Washington State
Department of Natural Resources. Most of this is publicly
owned, and a small amount is private land along the Du-
wamish River and in public rights -of -way. From the aptly
named 57th Avenue S Mini Park, less than a quarter acre in
total, to the 11 acres of mature deciduous trees battling in-
vasive ivy in Southgate Park, the city's natural areas range in
size, access, composition, and health. Many sites lie along the
Duwamish River and provide opportunities to collaborate
with larger efforts to help care for this landmark waterway.
Sites on school properties offer excellent spaces for outdoor
learning and youth engagement. Sites in the city's residential
areas are places where neighbors can come together, and sites
bordering industrial areas and business parks can engage
Tukwila's business community. All together, they have the po-
tential to provide much - needed spaces for outdoor recreation
and natural ecological processes within a highly developed
landscape.
For the purposes of this plan, forests are defined as the por-
tions of parklands with forested plant communities that have
greater than 25% tree canopy and are not mowed or orna-
mentally landscaped. The plan also encompasses natural areas
Defining the Project Area
Included in the Green Tukwila Partnership area:
• Forests
• Meadows
• Wetlands
• Streams
• Shorelines
• Buffers
• Future restoration sites intended to grow into one
of the above
NOT included in the Green Tukwila Partnership area:
• Ballfields
• Playgrounds
• Beaches
• Orchards
• Landscaped gardens
• Lawns and open fields
• Mowed stormwater detention ponds
• Hardscaped areas like parking lots and paved sport
courts
Green Tukwila 20 -Year Stewardship Plan 15
with less than 25% tree canopy — from riparian and wetland
buffers dominated by woody shrubs to forest edges domi-
nated by invasive species, and highly disturbed sites intended
for future restoration. Open water, such as in Tukwila Pond
Park and the Green - Duwamish River itself, is not included in
the Partnership's scope of work.
CHALLENGES AND THREATS TO
SUSTAINABILITY
Forests and natural areas in urban settings face unique
challenges and pressures that require specific attention. The
following section outlines six primary issues that prevent for-
ested and natural -area parklands from sustaining themselves
or pose risks to current and future ecological sustainability:
• Fragmentation
• Declining habitat quality
• Invasive species
• Native vegetation struggling to regenerate
• Illegal activity
• Climate change
Fragmentation
Habitat fragmentation is a problem common to urban
environments and occurs when contiguous open spaces are
divided, often by development, landscaping, sports fields,
and roads. This decreases valuable internal habitat areas and
increases "edge effects" along the exterior, thereby increasing
the habitat's exposure to human impacts. Edge effects refer to
the transition between two different habitat types and its ef-
fects on the plant and animal communities in the remaining
isolated open space. A greater proportion of edge increases
a forest's or wetland's susceptibility to encroachment by
invasive plants from adjacent landscaped areas and the likeli-
hood of water - quality issues due to polluted runoff (Brabec
et al. 2000). Habitats for birds, amphibians, and mammals
become isolated from each other with the loss of connectiv-
ity through greenbelts or connecting corridors. Because of
this unique pressure on forest and natural areas in urbanized
environments, restoration and maintenance of these areas are
distinct from that of large swaths of rural forests, for ex-
ample, and require continuous vigilance against the spread of
invasive plants and other edge effects.
16
Declining Habitat Quality
Several factors contribute to the loss of habitat quality in
Tukwila's forests and natural areas. Compared with the
region's native forest composition, deciduous trees make up
much more of Tukwila's forest canopy than is typical in a
healthy Northwest forest. These early - colonizing species help
establish a forest in disturbed areas, such as after the logging
activity that occurred throughout the Puget Sound in the late
1800s to early 1900s, and again in the mid- 1900s. Decidu-
ous bigleaf maples, cottonwoods, and alders now dominate
the majority of Tukwila's forest overstory. Under natural con-
ditions, as deciduous trees begin to die off, they are typically
replaced by longer -lived conifers; however, Tukwila's forests
and natural areas no longer grow under natural conditions.
The high proportion of deciduous trees in Tukwila's upland
forests indicates that there will be a pronounced decline in
tree canopy in the near future. In many areas, the conifer
seed bank has been lost through past logging and develop-
ment. Many of the deciduous trees — both native and
nonnative — are nearing the end of their natural life spans.
As they die, more sunlight is allowed to reach the ground,
resulting in perfect growing conditions for aggressive invasive
plants to flourish. The loss of tree canopy allows invasive
plants to become the dominant species in many parts of
Tukwila's natural areas, inhibiting the new growth of native
trees and understory. Without intervention to help ensure
that enough young native trees are present in the understory
to make up the next generation of canopy, this plan's techni-
cal analysis projects that the natural death of these deciduous
trees could lead to a loss of much of Tukwila's forest overstory
(Figure 2).
Additionally, past removal of vegetation, urban development,
and channelization along the Duwamish River and Tukwila's
many streams and wetlands resulted in a loss of native species
cover. Large stretches of the Duwamish River shoreline, as
well as smaller creeks, wetlands, and other sensitive areas, are
now buried under a blanket of invasive species such as Hima-
layan blackberry, English ivy, and Bohemian knotweed. The
loss of native vegetation along waterways results in significant
impacts on stream temperatures and water quality, and nega-
tively affects aquatic species, including threatened salmon.
Invasive Species: Plants
Invasive plants now outcompete native understory plants in
many of Tukwila's forests and natural areas. Aggressive, non-
native shrubs and vines cover the ground, blocking sunlight
from, and competing for nutrients with, native species.
Robust Himalayan and evergreen blackberry bushes spread
along the ground in large thickets, and birds disperse the
seeds to new locations. Invasive blackberry grows densely,
choking out native plants and destroying native habitat for
wildlife species. Blackberry thickets are especially aggressive
when establishing along creeks and gulches, including the
Green - Duwamish River shoreline. Himalayan blackberry is
the dominant invasive plant in Tukwila's natural areas: the
primary invasive species found in 39% of the Partnership's
project area, and present (as either the primary, secondary, or
tertiary invasive species) in 88% of the project area. English
ivy is the primary invasive species in 38% of the Partnership's
project area, and reed canary grass is the primary invasive
species in 22 %. One or more of these three species is found
in almost every site, and a small number of other aggressive
invasive species round out the full picture of the threat facing
Tukwila's struggling natural areas (see Figure 11).
English ivy can kill a healthy deciduous tree within 20 years
by spreading up from the understory into the tree canopy.
Ivy can easily spread from neighboring residential landscapes
into nearby parks, where it will become a serious problem,
as experienced by many other cities throughout the region.
Once ivy becomes established, an intense investment of time
and resources is required to remove it. 'Where English ivy is
in the early stages of blanketing forest floors and trees in Tuk-
wila, the opportunity exists to remove the existing growth
and prevent further spread and a much bigger future cost of
If forested parklands are not restored
Aggressive nonnative vegetation will dominate the urban forest unless
removed. In 100 years, the trees will be gone.
II/SENT �}
Forested parklands are
dominated by deciduous trees,
mainly bigleaf maples and
alders, nearing the end of their
life. After decades of neglect,
nonnative Invasive plants, such
as English ivy and wild clematis,
cover the ground and grow up
into the tree canopy;
IN 2GYEARS � ►
Invasive plants outcompete and
grow overexisting native
vegetation, blocking the sunlight
plants and trees need to thrive.
English ivy now dominates the
tree canopy, making the trees
weak, top - heavy, and susceptible
to wind throw_ Eventually, trees
die or fall over.
Figure 2. A projection of forest decline
IN Si YEAS
The trees are gave. Only a few
native shrubs struggle to
survive the stress of
competition with invasive
plants.
IN 100 YEARS
The forest is destroyed. Native trees
can no longer establish on their
own_ vile are left with a dense ivy
desert" Very few native understory
plants can live, and forest
biodi+versity is lost, These ivy
monocultures provide good homes
for unwanted rodents and poor
habitat for desirable urban wildlife.
Green Tukwila 20 -Year Stewardship Plan 17
management.
The native understory is an important food source for native
Pacific Northwest wildlife and provides much - needed cover
and shelter from predators and the elements. In addition
to Himalayan blackberry and ivy, other invasive species,
such as reed canary grass, Scotch broom, English holly, and
morning glory, grow in the understory, crowding out ferns,
shrubs, and other native plants. As invasive species begin to
dominate the understory, the diversity of food and habitat
available throughout the seasons is diminished. While some
animals, such as rats, can live and even thrive in the dense
monocultures of blackberry or ivy, quality habitat for most
native wildlife is degraded by invasive species.
Blankets of Himalayan blackberry on stream banks displace
native riparian vegetation. Lack of riparian tree cover also
decreases shade along creeks, causing water temperature to
rise, which reduces the amount of dissolved oxygen that the
water can contain. These altered conditions impair water
quality and overall suitability of salmon habitat in the Green -
Duwamish River and the streams that make up Tukwila's
watersheds.
In addition, environmental benefits such as stormwater re-
tention, erosion control, and carbon sequestration are greatly
decreased when invasive species displace complex communi-
ties of native vegetation that have grown together throughout
this region's history. If the spread of invasive species is not
prevented, the result is degraded forests and natural areas
overrun with sprawling thickets of blackberry and engulfed
in ivy.
Invasive Species: Insects
Native insect activity is a natural part of a healthy forest eco-
system. In fact, insects such as the native Douglas-fir beetle
are a needed food source for wildlife and continue natural
ecological processes. However, even small infestations of ex-
otic, invasive insects, in the context of the small, fragmented,
and oftentimes stressed forest stands that we find in our
urban environments, can negatively impact the sustainability
and resilience of Tukwila's trees and forests.
Exotic, invasive insects can have catastrophic effects on a re-
gion's natural resources and do not contribute to the natural
ecological processes found in healthy natural open spaces. For
example, states from Michigan to Colorado have seen urban
18
and rural forests decimated by the emerald ash borer. This
wood- boring insect targets ash trees, a deciduous hardwood
species. First documented in Michigan in 2002, borers have
now killed millions of ash trees in 22 US states and two Ca-
nadian provinces (Herms et al. 2014). They also pose a threat
to the native Oregon ash (Fraxinus latifolia) — a significant
component of riparian vegetation in Puget Sound lowlands
— present in Tukwila's Macadam Road South Site.
Another wood- borer, the citrus longhorned beetle (Ano-
plophora chinensis) — a species native to Southeast Asia —
was documented in a Washington State nursery in 2001 and
1,000 trees were removed from an area infected in Tukwila
(Boersma et al. 2006). Although the eradication was success-
ful and a population of these beetles does not yet exist in our
region, Tukwila and its surrounding areas still face the risk of
introduction. Wood - boring beetles have been documented
in the northeastern US and California since 1996. The
Asian long- horned beetle (Anoplophora glabripennis) and
the citrus long- horned beetle, which arrive on wood pallets
from Asia, are known to attack and kill maple trees and other
deciduous hardwoods (Haack et al. 2010).
Outbreaks of Asian and European gypsy moths have also
been documented in the Pacific Northwest, though successful
control efforts have prevented populations from establish-
ing. In areas where full populations have established, such
as in the Northeastern and Midwestern United States, gypsy
moths — which forage by defoliating trees— have weakened
trees and degraded wildlife habitat on millions of forested
acres. Weakened trees then succumb to other pests or disease.
In the Pacific Northwest, gypsy moths have been known to
attack red alder, Douglas -fir, and western hemlock (Boersma
et al. 2006).
To protect Tukwila's forests and natural areas, the Green
Tukwila Partnership will need to stay abreast of potential
invasive insect outbreaks in the region. Information is avail-
able to staff and volunteers through the Washington Invasive
Species Council and US Department of Agriculture (USDA)
Animal and Plant Health Inspection Service. The Green Cit-
ies program, with funding from the USDA Forest Service,
has developed a monitoring protocol for Asian long- horned
beetle species. This monitoring protocol is specifically de-
signed for citizen scientists and volunteers to assist in detec-
tion and could be offered as training for Green Tukwila forest
Stewards.
As the Green Tukwila Partnership implements its 20 -year
plan, insect pests and other forest - health threats should be
monitored at each restoration site as part of a detailed park
stewardship plan.
To protect urban forests and natural areas from devastating
future pest and disease outbreaks, it is absolutely vital that a
diversity of native trees and shrubs is planted at all restora-
tion sites. A landscape dominated by just one or a few species
is more vulnerable, as most pests and tree diseases attack only
certain species. A diverse landscape of different plant species
will be more resilient to all kinds of future uncertainties.
Native Vegetation Struggling to Regenerate
Native - tree - canopy regeneration — especially of conifers
— is greatly limited in Tukwila's forest and natural areas for
several reasons. The landscape -scale loss of native conifer trees
due to residential and commercial development has reduced
the seed bank for these trees. At the same time, invasive
plants have reduced native -tree regeneration by outcompet-
ing or smothering those tree seedlings that do grow. Removal
of nonnative invasive plants and planting native trees, shrubs,
and ground cover can help the process of native -tree regen-
eration move forward. This is critical to ensure the future
vitality of the city's urban tree canopy and natural areas, and
the many ecosystem and human health benefits they provide.
Illegal Activity
In addition to the indirect effects of human development,
illegal activity has had a direct impact on urban forest and
natural areas as well. Trees are damaged and cut for views
or firewood, or in acts of vandalism. Dumped garbage and
yard waste is a common problem in parks and natural areas
throughout the city. Yard waste forms a layer of debris that
smothers and kills native vegetation and contributes to slope
instability as it becomes water saturated and heavy. Invasive
plants from private yards can escape from dumped piles
and spread throughout parks. Garbage can leach chemicals
into the ground, attract rodents or other pests, and smother
understory vegetation. Encroachments onto public land from
adjoining private property and encampments bring with
them any number of problems for natural areas, including
removal of native habitat for the establishment of ornamental
landscaping, lawns, personal views, access paths, built struc-
tures, and domestic animals.
While addressing all types of illegal activity will require
sensitivity, the issue of homeless encampments is undoubt-
edly among the most complex. The Partnership will approach
encampments on project -area sites with sensitivity toward
all involved, and work with social services organizations
whenever possible to come up with plans of action in the
combined best interest of people experiencing homeless-
ness, neighbors, volunteers, and the parks and natural areas
themselves.
Additionally, the sanctuary from built environments that
forests and natural areas — especially areas without visible
management activity — provide can be a refuge for illegal
activity, such as drug use and violent crime. This is an un-
fortunate reality of open -space management that challenges
many communities, especially in an urban setting. When
enough illegal activity takes place, forest and natural areas
can become known more for the illegal pursuits they harbor
than for the valuable benefits they provide. Reversing this
perception takes a concerted effort to bring more atten-
tion and activity in general to such areas. Problems often
arise when people think of undeveloped parks as "empty" or
"abandoned" property.
However, as an important aspect of responsibly caring for
Tukwila's parklands, and for public spaces in general, ad-
dressing illegal activity provides significant opportunities
for community engagement. Restoration projects led by the
community help reclaim such areas as positive public spaces
for everyone by regularly bringing more watchful attention
to an area and increasing a sense of public ownership and
responsibility. The city also has policies and procedures in
place to ensure the safety of park visitors and volunteers.
Expanding public awareness and continuing to build a robust
Steward program that has high ownership and valuation of
forests and natural areas are therefore two main tenets of the
Green Tukwila Partnership.
Climate Change
The Pacific Northwest region faces climate- change impacts
that include warmer winters; hotter, drier summers; and
changes in precipitation (Littell et al. 2009). Climate change
is expected to negatively impact the health and resilience of
forests and natural areas by shifting the habitat conditions of
Green Tukwila 20 -Year Stewardship Plan 19
native tree species that are common in Puget Sound lowland
forests (Kim et al. 2012). Shifts in growing conditions, such
as changes to summer and winter temperatures and soil mois-
ture, can directly affect tree health and vigor, and make trees
more susceptible to mechanical or physical failure, insect
infestations, and disease (Littell et al. 2010).
Conservation and restoration of urban forests and natural
areas therefore become increasingly important in addressing
these changes by reducing urban heat - island effects, seques-
tering carbon, and mitigating stormwater impacts from
increased precipitation. The Green Tukwila Partnership's
restoration efforts are essential to preserve forest and natu-
ral area health, and ensure the critical ecosystem functions
these resources provide. To improve the ability of forests and
natural areas to mitigate as well as adapt to climate- change
stressors, Green Tukwila Partnership managers will need to
integrate adaptation and resilience strategies into their gen-
eral management practices and site -level stewardship plans.
Resource Limitations on Forest and Natural Area
Restoration and Maintenance
Historically, resources for natural area restoration and main-
tenance have been limited. The idea that forests and natural
areas in urban environments could take care of themselves
tended to discourage allocating sufficient funds for plant-
ing native species or removing invasive plants. Many forest
and natural areas across the Northwest were left to benign
neglect under the assumption that they were self - sustaining
and without the understanding that they were susceptible to
changing conditions and outside influence. This passive man-
agement has directly led to declining health in unsupported
urban forests and other natural areas. Unfortunately, but un-
surprisingly, the longer active management is postponed, the
more expensive it becomes, as existing tree canopy declines,
invasive species spread prolifically, and threats compound.
To reverse this trend, this plan recommends additional
investment in the active management of forested parklands
and natural areas. Natural succession cannot occur without a
conifer seed base and healthy understory, both of which are
currently missing or greatly impaired. Trees are now recog-
nized as city and community assets — or infrastructure —
and need to be maintained as such with attendant planning
20
and budgeting. Unfortunately, the level of need exceeds
current staffing and funding. By continuing to engage the
community in a more structured effort to manage forested
parkland, this plan seeks to leverage additional partner in-
vestment and volunteer engagement to target this need.
III. MEETING THE CHALLENGE
MISSION AND VISION
The Green Tukwila Partnership's mission is to engage the
community in caring for healthy forested parks and natural
open space in the city, protecting Tukwila's valuable natural
resources for current and future generations to enjoy.
The Partnership will be a collaborative effort bringing
together Forterra, the City of Tukwila, Tukwila and High -
line School Districts, Seattle City Light, Washington State
Department of Natural Resources, King County Parks,
Washington State Department of Transportation, and private
landowners, as well as other government agencies, nonprofit
organizations, educational institutions, local businesses, and
the Tukwila community at large. The Partnership's vision is a
city with healthy forested parks and natural open space, and
an engaged community invested in its urban environment.
Sustainable natural areas, specifically forests, will contain a
multi -aged canopy of trees, where invasive plants pose a low
threat, and a forest floor with a diverse assemblage of native
plants that provide a multitude of benefits (see Table 2).
If forested parklands are restored
Aga resy14,elyr ternoving invasive vegetation and planting natrvts trees and
shrubs will return the urban forest to a more sustainable condition_ In 100
years, the forest will provldc the city valuableservicees end better resist
tnuasIve plant Infestations
PRESENT
Forested parklands are
dominated by deciduous trees,
such as big leaf maples and
alders. nearing the end of their
Life. After decades of neglect,
nonnative invasive plants such
as English ivy are smother ng
native vegetation and
weakening native trees.
IN 2 YEARS
Theo ur. h restoration efforts and
hang -terra maintenance, the
nonnative plants are removed.
Native get undcovers, shrubs and
evergreen trees such as Douglas -
firs, western redcedars, and
hemlocks are planted.
Figure 3. A projection of forest restored
Ift se YEARS
As the everegreen trees grave, they
shade out sun Laving invasive
plants loth as Himalayan
blackberry, Native understary
plants thrive.
MN 100 YEARS
With continuer stewardship, the
maturing forest requires less care and
provides greater benefits to the city.
Green Tukwila 20 -Year Stewardship Plan
21
OUTCOMES
Achieving the Green Tukwila Partnership's long -term vision
will benefit the city in a variety of ways. Specifically, the
Partnership anticipates that success will bring the following
outcomes:
1. Improved health of Tukwila's urban forest and natural
open space, with all 138 acres enrolled in restoration and
active maintenance.
2. Quality-of -life enhancement through the public's in-
creased use and enjoyment of a healthy, safe, accessible
urban environment.
3. Positive economic and public health effects and enhance-
ment of ecosystem services that a healthy urban environ-
ment provides (cleaner air, cleaner water, stormwater
retention, safe access to recreation, wildlife habitat, com-
munity building, civic pride, and more).
4. Residents and employees of local businesses have a high
ownership stake in, and appreciation for, the city's urban
forest and natural open spaces.
GOALS
For the Green Tukwila Partnership's mission to succeed
and for the vision and desired outcomes to become a real-
ity, certain goals must be achieved during the next 20 years.
The following goals, along with measurable benchmarks
(see Appendix H), were developed based on current habitat
conditions, current capacity to support restoration efforts,
and the experience of other partnerships in the Green Cities
Network. Chapter 5, Adaptive Management, describes the
process of monitoring and tracking the program's success in
more detail.
1. Identify priority sites for restoration and maintenance,
and implement enrollment according to available re-
sources and funding.
2. Develop stewardship plans for priority sites to support
restoration implementation.
3. Host community events that foster the use and enjoy-
ment of, and connection with, forested parks and natural
open space in ways that are relevant to Tukwila's diverse
community and provide an introduction to stewardship
4. Recruit, retain, and support volunteers in meaningful
restoration and stewardship projects in local parks and
open spaces.
5. Develop a Steward program that empowers a growing
number of dedicated participants to take a leadership
role in restoration.
6. Build collaborative working relationships among govern-
ment agencies, nonprofits, schools, and other partners,
beginning with the formation of a Green Tukwila Man-
agement Team.
7. Establish resources to sustain the program for the long
term.
8. Celebrate the Partnership's success.
22
PARTNERSHIP ROLES AND
CONTRIBUTIONS
Based on the experience of the other Green Cities, this sec-
tion describes a management- structure model that has been
modified for the Green Tukwila Partnership (described in
Table 3). The structure is intended to support several thou-
sand community volunteers, city and nonprofit staff, and
skilled field crews, who will implement the Partnership by
performing the work needed to achieve plan goals. In the
Partnership's first two years, a primary task will be planning
and decision - making, working closely with Forterra as neces-
sary to establish a strong program. Once the program is up
and running, the Partnership will expand the Management
Team to help guide the program's planning and implementa-
tion to achieve plan goals. All three program areas (commu-
nity, fieldwork, and resources) should be part of this process,
including tracking and reporting each area's progress. In the
first five years, the focus is on building and supporting a
volunteer base, spreading program awareness, and demon-
strating restoration results on the ground. As community
support becomes established, staff time can be reallocated to
the fieldwork component, especially for volunteer manage-
ment and coordination of the work done by Stewards and
skilled field crews.
Support staff will help facilitate implementation work by co-
ordinating resources and communication across the Partner-
ship. There will also be a
need to seek the necessary
near -term funding and
resources to help meet
program goals. Partnering
organizations, such
as Forterra, Earth -
Corps, and other or-
ganizations and business-
es, can help provide staff,
support, and resources
not available through the
City of Tukwila.
During these initial
years, the Tukwila Parks
Commission will pro-
vide guidance and oversight in coordination with the Green
Tukwila Partnership Management Team. If there is enough
support from interested Tukwila residents, the Partnership
may benefit from establishing a Community Advisory Com-
mittee. This committee could include community members
and representatives from major donors and local corporate
sponsors, along with the city and Forterra. The key roles of
the Community Advisory Committee could be to advance
the larger goals of the Partnership, provide guidance regard-
ing budgets and funding, and garner community support.
All of this is designed to provide resources to support and
track on- the - ground fieldwork undertaken by volunteers and
skilled field crews (city staff, nonprofits, and other profes-
sional contractors). Without advance planning and structure
for the Green Tukwila Partnership, the fieldwork will not be
as successful, efficient, and organized as it should to achieve
the plan's goals during the next 20 years.
City of Tukwila
Parks and Recreation
The City of Tukwila Parks and Recreation Department cur-
rently manages the majority of the sites within the Green
Tukwila project area. Parks has a supply of field equipment
that may be available for restoration on natural area sites.
However, the Maintenance Division's crew is currently at ca-
pacity addressing Parks' ornamental plantings and lawn areas.
Green Tukwila 20 -Year Stewardship Plan 23
Parks staff members based at the Tukwila Community Center
currently do outreach and volunteer recruitment for a vari-
ety of city projects. They already help promote restoration
projects at Forterra and EarthCorps sites, and will continue
to promote additional Green Tukwila Partnership projects.
However, more capacity would be needed to expand this role.
Public Works
The City of Tukwila Public Works Department currently has
one Habitat Project Manager dedicated to mitigation, lev-
ies, and grant - funded projects on City property. Duwamish
Gardens is an example of a new off - channel habitat- restora-
tion project overseen by Public Works staff that will, once
completed, be handed over to Parks to manage. The Habitat
Project Manager has a high degree of knowledge of restora-
tion ecology, and as such will continue to provide advice to
the Partnership regarding site - management best practices.
Community Development
The City of Tukwila Department of Community Develop-
ment also has a staff members who will provide oversight for
the Green Tukwila Partnership, primarily the Environmen-
tal Specialist. The Environmental Specialist is familiar with
many of the sites in the Green Tukwila project area, especially
those containing sensitive areas and shorelines. However, this
position is half -time, and more capacity would be needed to
expand this role.
Seattle City Light
Green Tukwila sites under the ownership of Seattle City
Light include the three properties in the Creston - Duwamish
Green Line, the restoration corridor under and along the
transmission line between the Creston and Duwamish
substations. These sites are Ryan Creek, Ryan Hill, and
Duwamish Hill. An additional consideration for these sites is
the restriction on the height of trees under transmission lines.
There is currently a project being planned for restoration on
these sites with native shrubs and groundcover plants that
will attract and provide habitat for pollinators, such as bees,
butterflies, birds, and moths. There is already some volunteer
engagement on these sites.
24
King County Parks
Five sites within the Green Tukwila project area are currently
owned by King County Parks: Foster Point Lookout Park,
P -17 Pond, Cecil Moses Memorial Park, Chinook Wind,
and North Wind's Weir. EarthCorps' Puget Sound Stewards
program has been an active partner is restoration of the last
three sites listed above. EarthCorps will continue to help
steward these sites as funds are available in coordination with
King County.
Tukwila School District
The Tukwila School District owns several properties included
in the Green Tukwila Partnership project area: Tukwila and
Thorndyke Elementary Schools, Showalter Middle School,
Riverton Park, and Foster High School. The properties with
on -site schools present excellent opportunities to involve
students and classes in stewardship. The School District's
communications staff will help find opportunities for the
Partnership to reach students and families.
Highline School District
Crestview Park is the only site in the project area owned by
the Highline School District. Currently there is no school
located on the property. Crestview is a great neighborhood
park that would be a good potential early restoration site.
The City of Tukwila will act as an intermediary to the School
District until we are ready to bring this site into active resto-
ration.
Washington State Department of Transportation
The West Valley Riverbank is the only Green Tukwila site
under the ownership of the Washington State Department
of Transportation (WSDOT). As a significantly sized stretch
of Duwamish River shoreline, it is an important restoration
site. However, as a tree -iage category 9, with additional access
limitations, it is a low priority for the first few years of the
Partnership. Green Tukwila Partnership staff will coordinate
with WSDOT later in the program timeline when resources
are available to begin work on this site.
Washington State Department of Natural Resources
The Nelsen Site is the only Green Tukwila site under the
ownership of the Washington State Department of Natural
Resources (DNR). This site is divided into parcels, some of
which are under the ownership of the City of Tukwila. The
Nelsen site also includes some Duwamish River shoreline and
side channels, and so is an important restoration priority for
ecological reasons. However, like the West Valley Riverbank,
it is identified as a tree -iage category 9 site with difficult ac-
cess and would be a low priority for recreation or community
engagement. When the Nelsen Site is enrolled into active
management, Green Tukwila staff will coordinate with DNR.
Nonprofit Organizations
Forterra
Forterra is the state's largest conservation and community-
building organization working to create great communities
and conserve great lands. Forterra's Green Cities Department
supports all Green City Partnerships in some way, and works
to keep all Partnerships connected through the Green Cities
Network. The Green Cities Network facilitates quarterly fo-
cus groups open to all Partnership staff; distributes training,
grant, and other announcements via the Network listserv;
and offers technical and general assistance to participating
Green City partner agencies.
Forterra has already been invested in ongoing restoration in
Tukwila at the Duwamish Hill Preserve and the Duwamish
Shoreline Restoration Challenge site for many years. The
organization will continue its commitment to doing work
on these sites, and hopes to expand its work in Tukwila as
resources allow. Forterra will be an active member of the
Management Team.
Forterra will continue to work alongside partner agencies and
the public to articulate and advance the goals of the Green
Tukwila Partnership. Forterra may also provide additional
skilled field crews, program management, outreach, market-
ing, development, and greater coordination and connection
to the regional Green Cities Network, if needed, through
possible future grants or contract funding.
EarthCorps
With more than 20 professional staff and nearly 50 young
adult corps members working full time throughout the year,
EarthCorps has nearly 25 years partnering with local mu-
nicipalities, nonprofits and community groups on habitat
restoration projects in our region. EarthCorps professional
resources include highly trained crews working year round;
a group of long -term volunteers who adopt restoration sites
(Puget Sound Stewards); a team of volunteer coordinators
and volunteer specialists who lead 10- 12,000 youth and
community volunteers annually; and a professional staff that
includes project managers and ecologists skilled in develop-
ing vegetation management plans as well as mapping and
monitoring restoration sites.
The Student Conservation Association
The Student Conservation Association (SCA) runs youth
crews that work on environmental stewardship projects. In
the Seattle area, the SCR's summer crews for high school stu-
dents present an excellent opportunity to connect the need
for restoration at Green Tukwila sites with youth employ-
ment and job - skills training. High School members are paid
an hourly minimum wage rate. The SCA already recruits
crew members from Foster High School, and will seek to
deepen its relationship in Tukwila as the Green Tukwila
Partnership grows. SCA staff may join the Green Tukwila
Management Team as appropriate.
ECOSS
The Environmental Coalition of South Seattle (ECOSS)
currently runs a program for newly arriving residents to the
city, particularly the immigrant and refugee communities.
The program helps them get to know their new home and
its surrounding environment by offering information on
issues such as accessing and using public natural areas; and
the permits, rules, and regulations regarding harvesting and
recreation. The Green Tukwila Partnership will look for ways
to partner with ECOSS to create programming and events
that are culturally appropriate, appealing, and accessible to
Tukwila's large immigrant and refugee communities, and that
celebrate their use of public parks and natural areas. ECOSS
staff may join the Green Tukwila Management Team as ap-
propriate.
Other organizations
It is the Partnership's intent to look for opportunities to
collaborate with organizations that share common goals.
Reaching out to various nonprofit organizations and com-
Green Tukwila 20 -Year Stewardship Plan 25
munity groups that serve the Tukwila area and finding arenas
for mutually beneficial work will strengthen and leverage
community support for the program. Additional groups may
supplement work performed by Green Tukwila partner agen-
cies in the following capacities:
• Organize, recruit, support, lead, and /or train community
volunteers.
• Facilitate involvement of Tukwila residents, or civic,
business, and community organizations.
• Perform restoration work in areas that cannot be served
by volunteers or in areas where the Partnership directs
such work.
Volunteers and the Community at Large
Volunteers donate their time to the Partnership by helping to
restore and maintain forested parks and natural areas, leverag-
ing the financial resources of Green Tukwila partner agencies
and allowing more areas to be actively cared for. They bolster
community interest and support for local parks and natural
areas through their advocacy, and build critical local owner-
ship of, and investment in, public spaces. A key responsibility
of the Partnership will be to work with community members
to provide field leadership training, site planning assistance,
support, and encouragement. Volunteers committed to a
restoration site in their local park will be encouraged to take
on additional responsibilities and receive special training
as Stewards. An active and educated group of Stewards is
essential to expanding the Partnership's capacity to work in
many parks simultaneously, and will help shape the work to
fit the needs of particular neighborhoods and communities.
Individual volunteers and groups will be recruited to help
Stewards with their forest - restoration projects.
Commercial and Nonprofit Field Crews
Professional field crews and contractors will complement the
work of volunteers in achieving restoration goals. Professional
crews typically focus on steep slopes and other sensitive
areas not appropriate for volunteers, or projects that require
technical expertise beyond the scope of volunteers. Several
local training crews, including EarthCorps, the Student
Conservation Association, Washington Conservation Corps,
Duwamish Valley Youth Corps, and Duwamish Infrastruc-
ture Restoration Training (DIRT) Corps, provide excellent
26
Photo by McRob
Photo by Billy Hustace
Photo by McRob
opportunities to get restoration work done in Green Tukwila
sites, along with employment and job - skills development for
local residents, especially youth.
Funders, Donors, and Sponsors
This plan was made possible, in part, through a generous
grant from The Boeing Company. Corporate sponsors like
Boeing, foundations, private donors, and other grant - making
entities are key partners and stakeholders in the Green
Tukwila Partnership. These stakeholders may be able to help
address funding gaps in implementing the program.
Corporate sponsors will also have opportunities to support
the Partnership beyond financial donations. Many businesses
offer their employees opportunities to volunteer for vari-
ous community projects. Corporations and local businesses
will be invited to participate in volunteer restoration events,
providing a substantial volunteer labor resource. Sponsors
may also be asked to make other contributions as appropri-
ate. For example, it is not uncommon for firms to help defray
expenses by donating event supplies, coffee and snacks, or
services such as graphic design, advertising, or event planning
that can be provided through their companies. In return,
these corporations receive the opportunity to engage with the
Guide
City Council
Provides policy for larger Partnership goals and resource allocations.
Parks Commission
Provides advisory guidance and connection to the residential community.
roc
E.'
Green Tukwila Management Team
Implements Partnership goals, creates work plans, tracks accomplishments, and manages the
Partnership's resource allocations. The Management Team is made up of partner agency staff
involved in active work. As the Partnership grows, the Management Team may form committees,
which may include interested members of the public, to meet separately to address certain areas of
work (for example: fieldwork, public engagement, etc.).
a)
aa)
E
Public
• City of Tukwila
• King County Parks
• Seattle City Light
• Tukwila School District
• Highline School
District
• WSDOT
• Washington State
Department of Natural
Resources
• Volunteers
Nonprofits
• Forterra
• EarthCorps
• SCA
• ECOSS
• Others
Private
• Contractors and
consultants
• Local business partners
• Property owners
Table 3. Green Tukwila Partnership management structure
Green Tukwila 20 -Year Stewardship Plan 27
community and contribute to a healthier, more livable urban
environment.
Private Landowners
Private and public lands create a patchwork of natural areas
across the City of Tukwila. Private lands serve as vital con-
nectors between fragmented public green spaces. Many of
the pressures on Tukwila's forested parks and natural areas are
related to actions on adjacent private land, which can either
enhance surrounding public spaces or lead to their degrada-
tion.
Landscaping choices or lack of maintenance on private prop-
erty is a major source of invasive plants that spread to public
parks. Illegal dumping of yard waste on park property also
leads to the spread of invasive plants and smothers healthy
plant communities. Tukwila landowners who live adjacent
to forested parks are encouraged to be more active in stew-
ardship of their land. Efforts to educate landowners about
the benefits of native shrubs and trees, and the problems of
invasive species such as English ivy, can play a key role in pre-
venting the continued spread of invasive species throughout
the city. Working with landowners through education pro-
grams, landowner- incentive stewardship programs, and other
complementary programs for private property, will help the
Partnership generate a community that cares about the well-
being of natural areas, both on their own lands and in public
spaces. Engaging these landowners as invested stakeholders
will mobilize an important corps of advocates and volunteers
to reverse the trend and improve the health of their property
and the parks.
28
IV. FOREST AND NATURAL AREAS
ASSESSMENT
Effective and efficient natural - resource management can
only be accomplished if planners, field staff, and decision
makers have the environmental information on which to
base restoration actions. Armed with clear, systematically
collected data, the Partnership will be able to understand on-
the- ground conditions, identify the strategies and resources
needed to accomplish the work, and identify priorities.
In 2015, the Green Tukwila Partnership conducted a forest
assessment to characterize habitat conditions across the city's
parklands and develop its citywide restoration plan.
METHODS
The habitat assessment focused on the 138 acres of for-
ested and natural area parkland owned and managed by the
Partnership's agencies. The parcels included in the Partner-
ship's scope are those that currently support, or have the
potential to support, (1) native lowland- forest communities
with tree canopy cover greater than 25% and (2) forested and
shrub - dominated wetlands or emergent wetlands that do not
support a full tree canopy. While landscaped parks and street
trees provide important ecological benefits and should be
targeted for maintenance, they have not been included in the
current scope of work.
Tree -iage and the Forest Landscape Assessment
Tool
Baseline ecological data was collected during the fall of 2015
using a rapid - assessment data - collection protocol called the
Forest Landscape Assessment Tool (FLAT), developed by the
Green Cities Research Alliance (www. fs.fed.us /pnw /research/
gcra; see "Urban Landscape Assessment "). FLAT is based
on the "tree -iage" model, originally developed by the Green
Seattle Partnership. Tree -iage is a prioritization tool, based on
the concept of medical triage, that uses habitat composition
(e.g. canopy cover or native plant cover) and invasive plant
cover as the two parameters to prioritize restoration (Ciecko
et al. in press).
The FLAT adaptation builds on the existing framework of
the tree -iage model to characterize additional habitat at-
tributes beyond tree canopy and invasive plant cover. These
include tree age and size class, native understory species
present, and indicators of threats to forest health, including
low tree - canopy vigor, root rot, mistletoe, and bare soils due
to erosion. The presence of regenerating trees (canopy spe-
cies less than 5 inches in diameter at breast height) —which
play an important role in the long -term sustainability of the
forest —was also documented. In addition, each stand was
deemed "plantable" or "not plantable" based on whether site
conditions were appropriate for tree - seedling establishment.
Rapid- assessment methodologies such as FLAT produce a
snapshot of the overall condition at any one site and on a
landscape or city scale. The data serves as a high -level baseline
from which finer - scale, site - specific restoration planning can
be conducted; site -by -site analysis will need to be done as
work progresses to help ensure the most appropriate restora-
tion practices and species composition are chosen for each
site. Green Tukwila partners will continue to develop more -
detailed site -level stewardship plans to further assess planting
conditions and outline management recommendations as more
park sites are prioritized for restoration activities.
Prior to field data collection, natural areas within the Green
Tukwila Partnership project area were classified through digital
orthophoto interpretation, dividing each stand into one of five
categories: forested, natural, open water, hardscaped, or land-
scaped. These initial stand -type delineations were ground- verified
in the field, and if necessary, the delineations were corrected or
the boundaries were adjusted in the GIS. The delineated stands
are referred to as Management Units (MUs). All MUs were as-
signed unique numbers to be used for field verification and data
tracking. Hardscaped and landscaped areas, since they are not
suitable for active native vegetation management, were removed
from the total acreage targeted by the Partnership.
In the field, each MU was surveyed to identify its specific habitat
type (e.g., conifer forest, deciduous forest, riparian shrubland,
etc.). MUs were also surveyed to capture information on primary
and secondary overstory species and size class, as well as primary
and secondary understory species. (Primary refers to those species
most abundant in the MU, and secondary refers to the second -
most- abundant species.) See Appendix B for the FLAT - modified
data - collection flowchart for the tree -iage habitat composition
component of the model.
Green Tukwila 20 -Year Stewardship Plan 29
From this data, each MU was assigned a value (high, me-
dium, or low) for habitat composition, according to the
following breakdown:
HIGH:
MUs with more than 25% native tree - canopy cover, in which
evergreen species and /or madrones make up more than 50%
of the total canopy.
OR, MUs with more than 25% native tree canopy in par-
tially inundated wetlands that can support 1 % -50% ever-
green canopy.
OR, MUs in frequently inundated wetlands that cannot sup-
port evergreen /madrone canopy.
MEDIUM:
MUs with more than 25% native tree - canopy cover, in which
evergreen species and /or madrones make up between 1% and
50% of the total canopy.
OR, MUs with less than 25% native tree canopy in partially
inundated wetlands that can support 1 %-50% evergreen/
madrone canopy.
LOW:
MUs with less than 25% native tree -canopy cover.
OR forests with more than 25% native tree canopy, in which
evergreen species and /or madrones make up 0% of the total
canopy.
In addition, each MU was assigned one of the following
invasive -cover threat values:
HIGH: MUs with more than 50% invasive species cover.
MEDIUM: MUs with between 5% and 50% invasive species
cover.
LOW: MUs with less than 5% invasive species cover.
Tree -iage Categories
After habitat - composition and invasive - species -cover values
were assigned, a matrix system was used to assign a tree -iage
category or priority rating for each MU (Figure 4). Catego-
ries range from one to nine. One represents high - quality
habitat and low invasive - species threat, and nine represents
low - quality habitat and high invasive - species threat. An MU
that appears in tree -iage category three scored high for habi-
tat value and high for invasive cover threat. MUs scoring low
30
Habitat composition
4
7
LOW MEDIUM HIGH
Invasive species cover
Threat
Figure 4.Tree -iage legend
1
h
v w
E
O
}
4.23
9.64
r.39
23.66
2.70
LOW MEDIUM
Threat
4.26
59.55
22.79
Invasive species cover.
HIGH
Figure 5. Distribution of management acres across tree -
iage categories
1
Low
11%
Figure 6. Canopy composition
for habitat value and medium for invasive cover threat were
assigned to category eight based on the tree -iage model.
It is important to reiterate that this data was collected to
provide a broad view of the habitat conditions of Tukwilas
natural open spaces. Data collection occurred at the manage-
ment -unit scale. But because MUs are different sizes (ranging
from 0.02 acre to 9.14 acres), results are presented here using
F-)
Q V
90
80
70
60
50
20
10
0
i
Black cottonwood Bigleaf maple Douglas -fir
Low
Med
26%
Figure 7. Invasive cover
average conditions associated with each MU. Small pockets
within MUs may differ from the average across the stand.
When the plan refers to specific data in a given area, the term
"MU acre" will be used. Keeping in mind the purpose of the
FLAT analysis, this assessment will help prioritize restoration
efforts during the next 20 years. The data gathered will also
serve as a baseline from which the effectiveness of restoration
Sitka willow
Species
• Primary
Secondary
Tertiary
Red alder Pacific willow Pacific madrone Western redcedar
Figure 8. Distribution of overstory tree species by management -unit acres
Green Tukwila 20 -Year Stewardship Plan 31
70
60
50
40
30
20
10
0
Bigleaf maple Pacific willow
Red alder
• Primary
Secondary
Black cottonwood Douglas -fir
Species
Figure 9. Distribution of top five regenerating overstory species by management -unit acres
60
7
v
u
50
40
30
r
(..3< Ooh X6(6 4,°oa aea
Je•�\o� ��o� y`ao� ara�hQ
o
Sep
• Primary
Secondary
Tertiary
-44 k�y� y�r as<z, „() n4C\ aQQ\e Q���
<b DLO •
\\
Species
Figure 10. Distribution of most common native understory species by management -unit acres
32
efforts and the long -term health of Tukwila's forests and natu-
ral areas can be assessed in the future.
RESULTS
Tree -iage Matrix
From the data gathered on all MUs during the FLAT assess-
ment, a picture of Tukwila's forests and natural areas begins
to form. Figure 5 shows the distribution of acres in each
tree -iage category. By summing the acres in each row and
column, one can see how much of the total project area (138
acres) currently has low, medium, or high habitat value, and
how much currently has low, medium, or high threat from
invasive species.
This data informs the cost model discussed in Chapter V and
is used to develop high -level cost estimates for the Partner-
ship to consider when planning the next 20 years.
As seen in Table 5, just one percent of the Green Tukwila
Partnership project area is in exceptional condition (tree -iage
category 1) with high -value habitat and low invasive -cover
threat. Looking only at the first axis of the tree -iage matrix,
habitat composition, categories 1, 2, and 3 combined repre-
sent 11% of the acreage (see also Figure 6). Over half of the
140
120
100
171 80
2
60
40
20
0
acres have medium canopy composition
(64% in categories 4, 5, and 6). And
about 25% of the acres fell into the low -value habitat range
(categories 7, 8, and 9).
The second axis of the tree -iage matrix is the threat from
invasive species, which is based on the percentage of the MU
that is covered by invasive species (see also Figure 7). Sixty -
three percent of Tukwilas forested and natural area parklands
have a high invasive species threat (categories 3, 6, and 9).
Twenty-six percent of the project area falls in the medium
category (categories 2, 5, and 8) for invasive species threat
Photo byMcRob
Himalayan
blackberry
3
English ivy Reed- canary Scotch broom
grass
Species
■ ■
• Primary
■ Secondary
Tertiary
Knotweed English laurel English holly
European
hawthorn
Figure 11. Distribution of most common invasive species by management -unit acres
Green Tukwila 20 -Year Stewardship Plan 33
and 11% has low invasive species threat (categories 1, 4, and
7). Appendix C lists the tree -iage category acres per MU acre
per park.
Overstory Species
The 2015 FLAT results show that Tukwila's forested parks
and natural areas are dominated by middle -aged stands of
primarily deciduous tree species, including black cotton-
wood, bigleaf maple, and red alder. Some mixed stands of
conifer /deciduous canopy include Douglas-fir and, to a lesser
extent, western redcedar. Mature black cottonwood and big -
leaf maple were documented as the most dominant overstory
species (Figure 8). Note that trees were recorded in order of
dominance within each MU. Primary refers to acres where
the species is dominant, secondary is second most dominant
within a given MU, and tertiary is where the species is third
most dominant within a given MU, measured in acres of
each respective MU.
Regenerating Overstory Species
The top five regenerating tree species documented include
bigleaf maple, black cottonwood, Pacific willow, Douglas-
34
fir, and red alder. Bigleaf maple is by far the most prevalent
regenerating tree species in the Green Tukwila project area
(Figure 9). Regenerating trees indicate the sustainability and
future of the forest canopy, as these trees serve as the next
generation of dominant overstory in Tukwila's parks and
natural areas.
Native Understory Species
Tukwila's forested parks and natural areas have a variety of
native understory species. Salmonberry, beaked hazelnut,
snowberry, sword fern, and red osier dogwood are the most
common. For a complete list of native understory species
documented during the FLAT assessment, see Appendix E.
Invasive Species
Invasive species pose a very large threat to the understory in
Tukwila's parks and natural areas. 86% of the acres in the
project area were categorized as having a high level of invasive
cover (over 50 %).
In each MU, the top five most abundant invasive species
were documented. Figure 11 illustrates the top five shrub and
ground species, as well as the top three invasive trees. Hima-
layan blackberry and English ivy are the biggest threats. Out
of 138 total acres in the project area, Himalayan blackberry
was either the primary, secondary, or tertiary invasive species
found in 120 acres. Reed canary grass and English laurel were
also common, with other invasive species found throughout
the project area. See Appendix F for a breakdown of all inva-
sive species documented in the FLAT analysis.
Slope
Slope is also an important consideration, as it greatly affects
the difficulty of restoration activities. For safety reasons, vol-
unteers can only work on relatively flat terrain. Even profes-
sional crews need special equipment and training to work on
steep slopes, which increases the cost of restoration signifi-
cantly. For example, part of the Duwamish River shoreline
are quite steep, which will require extra planning, profession-
al crews and technical expertise. However, when comparing
the Green Tukwila Partnership project areas with other Green
Cities in the region, Tukwila has a relatively small percentage
of acres that have steep slopes. According to the FLAT data
that was collected; 47 acres are less than 20% slope; 83 acres
are 20% to 40% slope; and only 7 acres are on slopes greater
than 40 %.
Photo by McRob
Green Tukwila 20 -Year Stewardship Plan 35
V. MOVING 0RWARD THE
NEXT 20 YEARS
As in the other Green City Partnerships, a Balanced Score-
card approach is used to develop and adapt the Green Tuk-
wila Partnership implementation strategy (see Table 8). The
Balanced Scorecard is a widely used business tool that both
helps develop a strategy and monitor progress as that strategy
is carried out.
The Balanced Scorecard helps define and align the efforts of
complex organizations to achieve targeted outcomes. With
these metrics, the Partnership can track the success of vari-
ous activities and set benchmarks during the plan's 20 -year
course. The traditional private- sector scorecard balances
profits, customer satisfaction, and employee welfare by listing
goals and quantifying measures that indicate if actions meet
the goals. Its layers focus on increasing shareholder value.
For the Green Tukwila Partnership, the layers are modified to
reflect the ultimate goal of a healthy and sustainable network
of natural open spaces. These layers include the plan's key ele-
ments: field, community, and resources.
The FIELD element looks at how on- the - ground strategies
will be carried out to restore 138 acres of natural open space.
The COMMUNITY element assesses how an engaged com-
munity and a prepared workforce will be maintained in the
Habitat Value?
>1 acre of
high - quality habitat
or enhances connectivity
Yes
•
Community
support, volunteer
interest, or youth
engagement
opportunity?
Fo
long term, and how private landowners will be educated and
encouraged to complement the Partnership's efforts.
The RESOURCES element examines how sufficient finan-
cial, staff, and volunteer resources will be garnered to imple-
ment the plan.
The three elements have reciprocal relationships. For exam-
ple, volunteers are critical to accomplishing fieldwork, while
demonstrating progress in fieldwork is essential to motivat-
ing and retaining volunteers. Similarly, the Partnership needs
community support to secure the financial and volunteer
resources to restore and monitor sites in the long term. By
looking at the complete picture in layers that build on each
other, the Partnership can coordinate efforts across various
work areas so that activities are interconnected and mutually
supportive.
The ability of managers to track progress during the next 20
years will allow challenges to be identified early. In response,
managers can modify or adapt the program to address and
resolve those challenges. See Chapter 5, Adaptive Manage-
ment, for further discussion regarding the balanced scorecard
and adaptive management.
FIELD
Active management of Green Tukwila Partnership sites
will target removing invasive plants and establishing native
vegetation as appropriate. The citywide habitat assessment
Ye
Location improves
geographic
distribution of
restoration sites?
Financial and staffing resources available to support restoration?
4No
Y�
NOT A PRIORITY SITE AT THIS TIME
PRIORITY SITE
Create work plan;
begin restoration
and maintenance
Figure 12. Decision tree for prioritizing restoration sites
36
of Tukwilas forests and natural area parklands will be used
to assess progress in acres already enrolled in restoration,
characterize baseline ecological site conditions of new acres,
prioritize restoration efforts, and guide goal development.
Field Objective 1: Prioritize parks and natural open -
space sites
Tree -iage analysis results show that there are 138 acres of
forested parks and natural open space in Tukwila in need of
various levels of restoration, maintenance, and long -term
stewardship. To date, active partners (the City of Tukwila,
Forterra, and EarthCorps) have ongoing restoration projects
at six sites: the Duwamish Hill Preserve, Duwamish Shore-
line Restoration Challenge Site, Codiga Park, North Wind's
Weir, the Tukwila Community Center, and Cecil Moses
Memorial Park. In addition, the City has projects under way
at several sites, including the new off - channel habitat- resto-
ration project at Duwamish Gardens. The projects have thus
far been disconnected efforts. A goal of the Green Tukwila
Partnership is to take a comprehensive look across the city
and coordinate projects at different sites into a single over-
arching effort.
Currently active project areas will continue to be priorities
for restoration in 2017. The Partnership will prioritize new
sites based on a site's ecological condition, and community
interest and investment (see Figure 12). The Partnership
will try to ensure that restoration efforts are distributed
throughout the city so that they are accessible from every
neighborhood. For parks with an interested Steward or active
volunteer base, sites will be chosen that are appropriate for
volunteers (i.e., less than 40% grade) and where tools and
restoration materials can be easily accessed. Since commu-
nity engagement and education are key components in the
Partnership's success, sites with high public visibility and high
value to Tukwila residents will be chosen to extend education
and program promotion.
Field Objective 2: Prioritize restoration work zones
within sites
There are 53 sites included in the tree -iage analysis, each of
which contains management units falling into up to seven
different tree -iage categories, and each with different needs.
As individual parks are enrolled into active management,
forest stands and other natural areas within these sites should
be prioritized for annual and multiyear restoration plans. Par-
ticular attention should be paid to existing projects to keep
restoration efforts moving forward. Maintaining momentum
and preventing sites from reverting to their previous condi-
tion were comments made frequently during the public -in-
put phase of this plan development. As it is an inefficient use
of resources, not only is "backsliding" expensive, but it is also
particularly discouraging to the public. The second priority is
to expand sites already enrolled in restoration by continuing
to clear invasive species in areas contiguous with previously
cleared sites.
As new sites are brought into restoration, the tree -iage model
can be used within sites with multiple management units as
a guide to anticipate needed restoration. For example, MUs
with high - quality habitat and few to no invasive plants (tree -
iage category 1) can immediately be given the protection of
annual monitoring and maintenance. Other high -value habi-
tats, including conifer - dominated forests or wetlands made
up of a mosaic of native shrubs and emergent plants (tree -
iage categories 2 and 3), will be considered high priorities for
protection and restoration. Additional factors, such as public
access and safety, and the presence of wetlands, streams, or
shorelines are also taken into consideration. Providing main-
tenance for recently restored sites is a priority as well.
Field Objective 3: Identify areas that require
professional crew and staff support
As noted above, not all restoration sites in the Green Tuk-
wila project area are suitable for volunteers; some require the
use of professional, trained field staff. Sensitive areas such
as steep slopes, wetlands, and riparian buffers require the
expertise and training of such staff. In addition, some best
management practices require the use of herbicides, such as
cut -stump treatments for invasive trees like English holly and
cherry laurel, or stem injection for knotweed species that ag-
gressively invade critical riparian habitat. Herbicide treatment
must be conducted by a licensed professional staff member.
Sites that have support available through the City or part-
ner- or grant- funded crews will be given priority status for
restoration, as well as those where noxious weed control is
mandated by King County and that have support from the
King County Noxious Weed Control Program (www.king-
county.gov/ environment /animalsAndPlants /noxious- weeds/
Green Tukwila 20 -Year Stewardship Plan 37
program - information. aspx) .
Field Objective 4: Implement best practices in
restoration and stewardship on all project sites
Best Management Practices
Restoration ecology is an interdisciplinary science that draws
from the fields of ecology, forestry, and landscape horticul-
ture. As more restoration projects are completed in urban
environments, field practices are refined and improved.
Field experience and best available science will continue to
be integrated to improve techniques and restoration success
now and in the future. Ongoing restoration projects within
the Green Cities Network and other partner natural- resource
organizations will inform and guide best management prac-
tices (BMPs) for Tukwila's fieldwork. These BMPs include
site planning, invasive control methods, planting and plant
establishment, and volunteer management.
In 2012, the Green Seattle Partnership created a Forest Stew-
ard Field Guide of BMPs suitable for volunteer restoration
work, which has since been updated by and adapted for other
cities in the Green Cities Network. The Green Tukwila Part-
nership will create this field guide for Tukwila's Steward Pro-
gram. Program staff and volunteer stewards will be trained in
the BMPs. Supplemental coursework and training programs
will be recommended for all staff involved in restoration and
maintenance of Tukwila's forested parks and natural areas.
The Four -Phase Approach to Restoration Fieldwork
An important BMP, developed by the Green Seattle Partner-
ship, is the four -phase approach to restoration fieldwork,
which has been highly successful. It recognizes that restora-
tion activities fall into four major phases, and that, at some
sites, it takes several years to move through all the phases:
1. Invasive plant removal
2. Secondary invasive plant removal and planting
3. Plant establishment and follow -up maintenance
4. Long -term stewardship and monitoring
Because habitat health varies from site to site, and some work
is ongoing, not every site will start at phase 1. Each site, how-
ever, will need to receive an on- the - ground assessment before
work begins in the appropriate phase.
38
Phase 1. Invasive Plant Removal
The first phase aims to clear the site of invasive plants, focus-
ing on small areas at a time in order to help ensure thorough-
ness and minimize regrowth. Specific removal techniques will
vary by species and habitat type, and it may take more than a
year to complete the initial removal.
Major invasive -plant reduction will be required on sites with
50% or greater invasive cover (high threat from invasive
species: tree -iage categories 3, 6, and 9). Many of these areas
will require skilled field crews or special equipment. Given
the extent of invasive cover, these sites will also require a large
investment of both funding and community volunteers to
help ensure restoration success. Areas between 5% and 50%
invasive cover (medium threat from invasive species: tree -
iage categories 2, 5, and 8) will also require invasive removal.
Invasive growth in these spots is patchy. Generally, projects in
these sites are appropriate for community volunteers. Areas
with less than 5% invasive cover or less (low threat from
invasive species: tree -iage categories 1, 4, and 7) require little
or no removal, and phase 1 work in these areas may simply
involve walking through to check that any small invasive
growth is caught before it becomes a larger problem.
Phase 2. Secondary Invasive Removal and Planting
Before planting, a second round of invasive removal is done
to target any regrowth before it spreads, and to clear the site
for young native plants to be established. Staff will work with
each site on a case -by -case basis to develop an appropriate
plant palette and work plan.
For example, forested habitats with more than 50% conifer
canopy cover (tree -iage categories 1, 2, and 3) will require the
least amount of planting, but may need to be filled in with
ground cover, shrubs, and small trees in the understory. Areas
with more than 25% native tree cover but less than 50%
conifer cover (tree -iage categories 4, 5, and 6) will generally
be filled in with native conifer species. Areas with less than
25% native tree - canopy cover that can support tree canopy
cover (tree -iage categories 7, 8, and 9) will require extensive
planting with native trees, shrubs, and ground cover. Resto-
ration practices and planting requirements will, of course,
vary, depending on the habitat type and target native -plant
population. Most phase 2 planting projects are appropriate
for community volunteers. The Green Tukwila Steward Field
Guide will provide volunteer- appropriate BMPs once a plant-
ing plan has been established.
Phase 3. Plant Establishment and Follow -up
Maintenance
This phase repeats invasive plant removal and includes weed-
ing, mulching, and watering newly planted native plants un-
til they are established. Although native plants have adapted
to the area's dry summer climate, installed container plant-
ings and transplanted plants both experience shock, which
affects root and shoot health; therefore, most plants require
at least three years of establishment care to help ensure their
survival. Sites may stay in phase 3 for many years.
1
w
2
z
_D
6
W
z
a)
m 0 cd
Monitoring &
Maintenance
Planting,
Maintenance &
Monitoring
Evaluation &
Possible
Planting
Invasive Plant
Removal
Invasive Plant
Removal &
Planting
Invasive Plant
Removal &
Major Planting
Major Invasive
Plant Removal
Major Invasive
Plant Removal
& Planting
Major Invasive
Plant Removal &
Major Planting
LOW MEDIUM HIGH
Threat
Figure 13. Restoration strategies and tree -iage categories
Green Tukwila 20 -Year Stewardship Plan 39
Phase 4. Long -Term Stewardship and Monitoring
The final phase is long -term site stewardship, including
monitoring by volunteers and professionals to provide in-
formation for ongoing site maintenance. Monitoring may
be as simple as neighborhood volunteers patrolling park
trails to find invasive species, or it could involve regular
measuring and documentation of various site characteristics
and plant survivorship rates. Maintenance will typically
consist of spot removal of invasive regrowth and occasional
planting where survivorship of existing plants is low. Indi-
vidual volunteers or small quarterly or annual work parties
can easily take care of any needs that come up, as long as
they are addressed promptly before problems spread. The
number of acres in phase 4 is programmed to grow every
year, with the goal that all 138 acres will be enrolled in the
restoration process and graduate to this phase.
Without ongoing, long -term volunteer investment in
monitoring and maintenance of areas in restoration,
Tukwila's natural areas will fall back into neglect. For that
reason, volunteer commitment needs to be paired with city
resources. Work is then compared against the best available
science to define optimal plant stock and sizes, watering
regimes, soil preparation, and other natural open -space
restoration techniques.
Monitoring will be conducted more frequently in the early
phases of the program as the Partnership discovers how
the sites respond to restoration. Management units that
currently have less than 5% invasive cover and more than
50% native conifer - forest cover or healthy wetland vegeta-
tion (tree -iage category 1) may already be in phase 4 and
suitable for enrollment into a monitoring and maintenance
plan. Most management units will need some preliminary
restoration in phases 1 through 3.
In 2012, the Green Cities program developed a Regional
Standardized Monitoring Program in order to understand
the success, value, and effectiveness of restoration activi-
ties throughout the Partnerships. These protocols provide
procedures for baseline and long -term data collection
that can be replicated in the future to measure changes in
site characteristics. The data shows the composition and
structure of a site, which can be an important indicator of
overall habitat health.
40
APPLICATION TO THE TREE -IAGE
CATEGORIES
The four -phase approach can be applied to the tree -iage cat-
egories as shown in Figure 14. Each tree -iage category can
be assigned appropriate management strategies.
TREE -IAGE CATEGORY 1: High Habitat
Composition, Low Invasive Threat
Acres in project area: 1.27
Condition: This category contains the healthiest forest
areas in the Tukwila system of natural open spaces. Typical
stands have more than 50% evergreen canopy. This category
includes stands of mature conifers and the mixed conifer/
deciduous stands found in forested wetlands. In scrub -shrub
or emergent wetland areas, where full conifer coverage
would not be appropriate, this category has full cover by
native vegetation appropriate to the site. These stands are
under low threat because the invasive cover is less than 5 %.
Management Strategy: Monitoring and Maintenance
Work is focused on protecting these areas' existing high
quality and making sure that invasive plants do not establish
themselves.
TREE -IAGE CATEGORY 2: High Habitat
Composition, Medium Invasive Threat
Acres in project area: 9.39
Condition: Similar to category 1, these forest stands contain
more than 50% conifer or evergreen broadleaf canopy or ap-
propriate native wetland vegetation. Forests in this category
are at risk because the invasive cover is between 5% and
50 %. In these areas, invasive growth is expected to be patchy
with diffuse edges.
A forest in otherwise good condition but subject to a number
of moderate threats may degrade if left untreated. If unat-
tended, this level of invasive coverage could prevent native
seedlings from establishing and could compete with exist-
ing trees for water and nutrients. However, the forest would
persist in good condition if threats were mitigated in a timely
manner.
Management Strategy: Invasive Plant Removal and Prompt
Action
The main activity is removing invasive plants. Typically, these
sites will also require site preparation (e.g., mulching) and
infill planting. Projects in these areas are appropriate for vol-
unteers. Removing invasive plants from these areas is a very
high priority for the first five years.
Green Tukwila 20 -Year Stewardship Plan 41
TREE -IAGE CATEGORY 3: High Habitat
Composition, High Invasive Threat
Acres in project area: 4.26
Condition: As in categories 1 and 2, forest stands in this cat-
egory have mature conifers, madrones, forested wetlands, or
wetland vegetation where appropriate. Category 3 areas have
a high threat from greater than 50% invasive cover.
A forest in this category is in a high -risk situation and
contains many desirable trees or highly valuable habitat or
species. If restored, forests in this category can completely
recover and persist in the long term.
Management Strategy: Major Invasive Plant Removal and
Prompt Action
Without prompt action, high - quality forest stands could be
lost. Category 3 areas require aggressive invasive removal.
Soil amendments and replanting are needed in most cases.
Restoration efforts in this category are a top priority for the
first five years.
42
TREE -IAGE CATEGORY 4: Medium Habitat
Composition, Low Invasive Threat
Acres in project area: 4.23
Condition: Forests assigned a medium tree - composition
value are typically dominated by native deciduous trees but
have at least 25% native tree cover. Between 1% and 50%
of the canopy is made up of native conifers. In wetland areas
not suitable for conifers, these areas have between 1% and
50% cover by appropriate wetland vegetation. Category 4
areas have low levels of invasive plants, covering less than 5%
of the management unit.
Management Strategy: Planting and Monitoring
We expect planting in these areas to consist of infilling with
native species and establishing conifers to be recruited into
the next generation of canopy. Often these sites require some
invasive removal and site preparation (e.g., amending with
woodchip mulch). Many of these sites may be converted to a
conifer forest by the addition of appropriate conifer trees.
Addressing category 4 forests is a high priority during the
first five years. They offer a high likelihood of success at a
minimum investment. These sites are well suited to commu-
nity-led restoration efforts.
TREE -IAGE CATEGORY 5: Medium Habitat
Composition, Medium Invasive Threat
Acres in project area: 23.66
Condition: Areas in this category have between 5% and
50% invasive cover. Invasive growth is expected to be patchy
with diffuse edges. These areas are estimated to have greater
than 25% native canopy cover but less than 50% coniferous
or broadleaf evergreen canopy cover. In the case of wetland
forests, it is greater than 50% native tree canopy cover. In
wetland areas not suitable for conifers, these areas have
between 1% and 50% cover by appropriate wetland species.
These forest stands contain many desirable native trees that
are under threat from invasive plants.
Management Strategy: Invasive Plant Removal and Planting
These sites will require invasive removal and infill planting.
While some restoration work is planned for these areas in the
first five years, aggressive efforts are required throughout the
life of the Green Tukwila Partnership.
TREE -IAGE CATEGORY 6: Medium Habitat
Composition, High Invasive Threat
Acres in project area: 59.55
Condition: These areas are typically dominated by native
deciduous trees but have at least 25% native tree cover.
Between 1% and 50% of the canopy is made up of native
conifers. In wetland areas not suitable for conifers, these areas
have between 1% and 50% cover by appropriate wetland
vegetation. Invasive plants cover more than 50% of the man-
agement unit.
A forest that retains important plant elements but is already
partially degraded by a high -level risk factor may still have
the potential to recover if remediation is prompt. Because
these stands are at greater risk than category 5 forests, they
also require greater labor investment.
Management Strategy: Major Invasive Plant Removal and
Planting
Extensive invasive removal, site preparation (e.g., amending
with woodchip mulch), and replanting are required. Initial
invasive removal may be done with the aid of mechanical
tools and equipment, and may require professionals. Planting
in these areas consists of infilling with native species.
Green Tukwila 20 -Year Stewardship Plan 43
TREE -IAGE CATEGORY 7: Low Habitat
Composition, Low Invasive Threat
Acres in project area: 9.64
Condition: These forests are estimated to have less than 25%
native canopy cover in a setting that could support full cano-
py cover under good conditions. Forested wetlands will have
less than 25% trees or shrubs appropriate to the site. Levels
of invasive plants are low. Parks in this category may include
areas with large canopy gaps (perhaps due to windthrow or
die -off of mature deciduous trees), sites of recent landslides,
unstable slopes, sites with large amounts of fill, and /or areas
dominated by nonnative trees.
Management Strategy: Evaluation and Possibly Planting
The reasons underlying these sites' low value can differ
greatly, and the stands will be addressed on a case -by -case
basis. Because of low levels of invasive plants, restoration may
be quite cost - effective in some sites. Sites will be evaluated to
determine whether conditions and timing are appropriate to
move these areas toward a more native forest and what the
appropriate composition of that forest should be. In some
cases, it may be desirable to remove nonnative trees, especial-
ly if they are aggressive. Areas that are ready for conversion
to native forest would be a high priority during the first five
years.
44
TREE -IAGE CATEGORY 8: Low Habitat
Composition, Medium Invasive Threat
Acres in project area: 2.7
Condition: Areas that are estimated to have less than 25%
native tree - canopy cover or forested wetlands with less than
25% cover by trees, and 5% to 50% invasive cover fall into
this category Invasive growth in these areas is likely to be
patchy with diffuse edges. A forest in this category might be
chronically degraded by a variety of threatening processes,
and might have lost much of its value in terms of habitat
quality or species complement.
Management Strategy: Invasive Plant Removal and Major
Planting
Restoration efforts in these areas require a large investment
of time and resources. Although some work will be directed
here, this is not a priority category for the first five years. The
Partnership will support efforts that contain the spread of
invasive plants, try out new techniques, or help enthusiastic
community-led efforts. These sites will require major invasive
removal and site preparation, such as mulching and infill
planting. Planting within these areas will consist of infilling
with native species.
TREE -IAGE CATEGORY 9: Low Habitat Composition,
High Invasive Threat
Acres in project area: 22.79
Condition: Areas estimated to have less than 25% native tree -
canopy cover or appropriate forested wetland vegetation and
greater than 50% invasive cover fall into this category.
Management Strategy: Major Invasive Plant Removal and Ma-
jor Planting
Category 9 sites are not likely to get much worse during the
next five years. These sites require many years of major inva-
sive removal and site preparation in the form of mulching and
infill planting, and will almost definitely require the attention
of professionals. Although work will be directed to category 9
forests in the future, this is not a priority category for the first
five years. The Partnership will support efforts that contain the
spread of invasive plants, try out new techniques, or bolster
enthusiastic community -led efforts.
COMMUNITY
Community Objective 1: Promote positive
engagement with parks and natural open space
This is a major priority driving all the work of the Green
Tukwila Partnership. We believe that Tukwila's residents,
employees, and visitors deserve great parks and natural
areas, and that they shouldn't have to travel far to get there.
We want to make sure that there are places to enjoy nature,
both for its environmental services as well as for its benefits
for health and well- being, for the future of the city and its
people.
Restoration and active maintenance are critical for the enjoy-
ment of these natural areas, so that trees can thrive and we
don't lose them altogether. Volunteer projects that build com-
munity among neighbors also increase a sense of ownership
over public spaces and foster a special connection to them,
in addition to just getting people outside. The Partnership
will also plan and hold events that get more people out into
Tukwila's parks and natural areas, and encourage and inspire
them to see these places as the incredible public assets that
they are.
Community Objective 2: Prioritize safety and use
Partnership efforts to contribute to public safety in
the city
Safety is also a key priority for the Partnership. Active main-
tenance and regular community events promote more active
use of public spaces. As both volunteers and staff frequent a
site, care and stewardship become evident and decrease the
sentiment that parks are forgotten, abandoned places; as well,
providing more "eyes on the park" discourages illegal activity.
Safety concerns will also be taken into account in site selec-
tion.
Crime Prevention Through Environmental Design (CPT-
ED), a set of landscape- design principles aimed at increas-
ing safety, will be utilized in Green Tukwila projects. From
relatively straightforward best practices in trail planning and
maintenance to optimize safe view corridors, to complex
challenges for activating spaces, these principles will provide
valuable insights.
46
Community Objective 3: Develop and implement
a community outreach and engagement plan
to equitably serve Tukwila's diverse residential
population
Tukwila's residential population is incredibly racially and
ethnically diverse. Creating programs that are culturally
relevant, accessible, and enjoyable for the many people who
call Tukwila home will be essential to forming a Partnership
that equitably serves this community. By continuing to build
relationships with local organizations, community groups,
and houses of worship, and by reaching out and listening to
local residents, we hope to provide a variety of ways for them
to engage with the Partnership.
There are two existing programs that have already had success
in engaging Tukwila's recent immigrant and refugee commu-
nity, and it would be a great asset to collaborate with them
on stewardship efforts. The New Arrivals program, offered
by the Environmental Coalition of South Seattle (ECOSS),
helps recently immigrated residents get orientated to the
parks system and can foster a positive relationship with local
natural areas. The Community Connectors program, in part-
nership with the City of Tukwila, Global to Local, and Fort -
erra, provides a way for residents from immigrant communi-
ties to voice their opinions and give feedback on community
engagement efforts, thanks to the work of paid liaisons from
within their own communities. Green Tukwila staff will work
with both of these programs over the years to create events
and experiences that traditionally underrepresented residents
can relate to and enjoy.
Community building and an ethic of environmental respon-
sibility are at the core of the Green Tukwila Partnership and
the Green Cities Network across the Puget Sound. Com-
munity members are encouraged to participate in caring for
our shared public urban forests and natural areas regardless of
age, income, ethnicity, or languages spoken at home. Restora-
tion volunteer projects provide an opportunity for neighbors,
classmates, families, friends, and complete strangers to come
together to restore health to their parks, build community
through shared experience, and deepen ties to the natural
world and each other.
The Green Tukwila Partnership seeks to build a success-
ful volunteer program by strengthening efforts to provide
equitable and inclusive opportunities for the entire Tukwila
community Environmental conservation organizations across
the country and here in Puget Sound typically have trouble
engaging communities of color, recent immigrants, and
low- income families (Taylor, 2014). Tukwila's population has
become increasingly diverse, with Asian and Pacific Islander,
African American, and Latino populations all highly repre-
sented at 19 %, 18 %, and 12% respectively, and the white
population representing 44% of the community (Tukwila
census, 2012). In addition to seeking opportunities to work
with existing successful community- engagement programs,
the Green Tukwila Partnership will need to employ addition-
al creative strategies of its own during the next 20 years. The
following is a summary of suggested strategies to enhance
social equity and diversity, with input from Forterra and a
diversity- engagement best practices pilot project researched
and undertaken by the Green Redmond Partnership:
• Understand the demographics of Tukwila's neighbor-
hoods as well as the needs and priorities of the commu-
nities that live there.
• Attend community association or other community-
sponsored meetings, prioritizing those reaching com-
munities of color, recent immigrants, and low - income
families. Develop an understanding of this cohort's
values and goals, and how Green Tukwila can support
the neighborhood's own efforts to build community.
• Work cooperatively with human - services staff and local
nonprofit organizations that work closely with low -in-
come and traditionally underserved communities to cre-
ate events that will be inclusive, relevant, and enjoyable.
• Work with local community groups to craft and host
their own Green Tukwila events to increase inclusion in
the planning process and create a strong community-
driven program.
• Consider cultural competency training for Partner-
ship staff and be mindful of differences within cultural
groups. Don't make assumptions: be sensitive to the
traditions and views of the groups the Partnership is
working with.
• In an effort to ensure that public communication materi-
als for projects or events can be understood by target
residents, the Partnership can utilize King County's
language- translation resources to conduct neighborhood -
specific language -needs assessments. This resource is
based on five sources of Limited English Proficiency data
and includes GIS "language maps" that enable staff to
identify the language needs of populations specifically.
To help supplement the County's information, City staff
can also utilize the Tukwila School District enrollment
profiles for neighborhood schools.
• When working with Limited English Proficient vol-
unteers, language interpretation should be provided
throughout the volunteers' Green Tukwila experience,
including during recruitment and pre -event communi-
cation, at the restoration event itself, and following the
event, in order to build future engagement. The Part-
nership may choose to start with one language, such as
Spanish, and build from there based on need and com-
munity interest.
• Create public- facing materials that specifically show di-
verse community members, so that potential volunteers
can see themselves in Green Tukwila. Utilize inclusive
language such as "everyone can help," and seek feedback
from volunteers themselves on how to make events as
welcoming as possible.
• Provide a continuum of opportunities in various parks
and neighborhoods that are easily accessible and take
specific transportation needs into account — whether that
is public transit, available parking, walking access, or
shuttles when possible. Identify other barriers to partici-
pation and address them as resources allow.
• Consider providing food and other hospitality. Sharing
a simple meal together, even if it is a picnic at a natural
area park, is an effective community- building tool and
can be a great incentive to participation. Work with
Healthy Tukwila (a program of the City of Tukwila) and
other healthy food and local food programs to coordinate
efforts. If working with a specific cultural group, research
customs and norms, if any, surrounding food. When in
doubt, ask community members about their preferences.
• Look for opportunities to connect with and celebrate
different community's connections to the environment,
green spaces, and /or volunteerism through cultural holi-
days or in other ways.
• Find new places to spread the word by asking communi-
ty members where they gather and where they get news.
Utilize ethnic media outlets, and post flyers in popular
Green Tukwila 20 -Year Stewardship Plan 47
local businesses.
• Focus on working with more volunteers of color, recent
immigrants, and low- income families to move up the
chain of engagement and become leaders in their own
communities. Look for barriers to higher engagement
and address them.
• Realize that volunteering and the free time required
to do so is a privilege that is not available to everyone
equally. Look for ways to make volunteer projects as ac-
cessible as possible, and to provide outdoor engagement
and healthy, safe public spaces that benefit those who
may not be able to volunteer. Use training and job- skills-
development field crews as a way for more people to
participate in the work of the Partnership.
Community Objective 4: Work with local businesses
to encourage corporate support for the Partnership
Corporate support will be needed in order for the Partner-
ship to reach its goals. Local businesses have already been
involved in restoration projects in Tukwila, primarily through
the Duwamish Shoreline Restoration Challenge. We will
build on these relationships and expand to work with other
businesses as well. Corporate support could come in the form
of encouraging employees to volunteer, providing in -kind
resources, or financial support through grants and donations.
Community Objective 5: Seek opportunities to
engage youth and provide education
The Green Tukwila Partnership will work with the Tukwila
School District to engage youth in outdoor experiences and
environmental stewardship. Students at Tukwila Elementary
School, Thorndyke Elementary School, Showalter Middle
School, and Foster High School will be able to get involved
with restoration and stewardship projects on their own cam-
puses.
Studies have shown that students' productivity and creativ-
ity is increased by experiencing natural surroundings, due to
nature's calming effect and its ability to reduce mental fatigue
(Kaplan 1995 and Hartig et al. 1991).
By working with local partners providing engagement op-
portunities for youth at various ages, we will seek to create
a pathway of engagement from elementary school through
high school and job - skills training. Inspiring Connections
48
Outdoors is a Sierra Club volunteer -led program that pro-
vides free fun, active, outdoor trips for students at Tukwila
Elementary School and Showalter Middle School. The
Student Conservation Association summer crews are a great
opportunity for paid summer work and restoration - skills
training for high school -age students. EarthCorps and DIRT
Corps are local training crews for young people, who can
make a living while contributing to projects that improve
local environmental health. All these programs are currently
available to Tukwila youth. The Green Tukwila Partnership
will link them together, pursue funding opportunities that
would provide support for all these efforts, and provide ad-
ditional opportunities for youth and families to volunteer to-
gether in their local parks and green spaces, further improv-
ing their access to safe and healthy outdoor public places.
The Duwamish Valley Youth Corps, run by the Duwamish
River Cleanup Coalition, brings together excellent environ-
mental- justice education with restoration- and landscaping -
skills training for middle and high school students. Currently,
it is available for Seattle Youth, and members participate
in projects in South Park and Georgetown. With sufficient
funding, DRCC could run a similar program in Tukwila as
part of the Green Tukwila Partnership.
Community Objective 6: Build a Steward Program to
promote and support community leadership
The intent of the Green Tukwila Steward Program is to build
an educated, engaged, and active volunteer base around res-
toration, maintenance, and stewardship of Tukwila's forested
parks and natural areas. The program provides volunteers
with an opportunity to take on leadership responsibilities,
expand their skill set, tackle larger challenges associated with
restoration and maintenance, and receive support and guid-
ance to complete projects that improve the health of public
spaces they care about. The Partnership will build on the
success of existing volunteer leadership programs, such as
the Friends of the Duwamish Hill Preserve and EarthCorps'
Puget Sound Stewards program, to build a community of
dedicated volunteer leaders across Tukwila. Trained Stewards
will work with the Partnership in the following ways:
• Attend regular training events, including a program
orientation and more skill- specific training as resources
allow.
• Serve as key contacts for the Green Tukwila Partnership
projects in their site.
• Organize and lead volunteer events and activities in their
site.
• Coordinate with staff to develop site restoration plans.
• Request tools, materials, and assistance as needed.
• Track and report progress on restoration activities via the
Partnership's work log.
• The Partnership will support them with staff time,
resources, and guidance in site planning and restoration
work.
Community Objective 7: Appreciate volunteers and
publicly celebrate Partnership successes
The Green Tukwila Partnership will continue to celebrate
volunteers' achievements and emphasize the crucial role
they play in restoring and maintaining Tukwila's forested
parks and natural areas.
Volunteers are a valuable resource and are crucial for
completing on- the - ground Partnership goals. Stewards
and volunteers are the very heart and soul of the Green
Tukwila Partnership and are valued for their expertise and
the rich and diverse perspectives they bring, not only to
community engagement, but also on- the - ground stew-
ardship practices. The Partnership will regularly seek the
advice of volunteers on which best management practices
work well and which may need reassessment. The Green
Tukwila Partnership will host volunteer - appreciation
activities, such as an annual picnic for Green Tukwila
Stewards and volunteer appreciation at community vol-
unteer events. The Partnership seeks to find a variety of
ways to recognize Stewards and other volunteers for their
valuable efforts.
Community Objective 8: Engage and educate
residents and private landowners
While stewardship of public forest and natural areas is
an important step toward protecting habitat for wildlife,
improving water quality, and providing public recre-
ational opportunities, private properties cover a greater
portion of Tukwila s land area. Plantings on private lands
can greatly degrade the condition of the city's parklands
despite best efforts to restore, maintain, and steward these
areas. For instance, English ivy growing as a border plant in
a landowner's backyard can quickly escape into a forested or
natural -area park either by spreading beyond the property
line or by birds dispersing the seeds. Many invasive species
also spread when yard waste is illegally dumped in parkland.
In fact, these are the most common ways public forest and
natural areas become infested with invasive species.
Alternatively, landowners can be a great resource for their
neighborhood parkland by engaging their neighbors, schools,
community groups, clubs, and businesses to help support the
Partnership's efforts. Private land can also be a main source
for retaining trees and expanding current forest canopy and
Photo by Nick Krittawat
Green Tukwila 20 -Year Stewardship Plan 49
habitat. Privately owned forest and natural areas in good
health can serve as important buffers to adjacent public
parklands and help mitigate habitat fragmentation and edge
effects.
Potential ways for the Green Tukwila Partnership to educate
and engage private landowners as an important constituency
include:
• Developing mailings and handouts to inform them
about the problems facing forested and natural -area
parklands, the benefits of removing invasive species from
their properties and replacing them with native or non-
invasive ornamental species, and ways to get involved in
the Partnership.
• Providing information about the Green Tukwila Part-
nership's efforts on the Partnership's webpage, in park
kiosks, and in neighborhood newsletters and local news-
papers.
• Connecting private landowners with programs such as
the National Wildlife Federation's Certified Wildlife
Habitat or Schoolyard Habitats.
• Training landowners in best management practices
through the Green Tukwila Steward Program.
• Continuing to work with other City departments to
disseminate a stewardship - friendly plant list for develop-
ers and landowners that discourages invasive species and
promotes native or noninvasive species and tree reten-
tion.
RESOURCES
Financial resources, staff capacity, and volunteer
contributions will affect the Green Tukwila Partnership's
ability to restore and maintain the 138 acres identified for
stewardship in this plan. During the next 20 years (2017-
2036), the Partnership will need an estimated $5.73 million
in funding (2016 dollar value), as well as volunteer support,
to accomplish the proposed goals. The goal of volunteer
investment is 71,500 hours over the life of the program. This
will leverage an additional value of $2 million as a match to
the estimated $5.73 million in direct costs. Volunteer time
is valued at $28.99, based on the 2015 Independent Sector
valuation of a volunteer hour in Washington State. This is an
ambitious plan that relies on additional resources.
As a true partnership there will be many entities involved
50
Table 4. Land ownership (acres)
Ownership
Acres
City of Tukwila
87.57
Tukwila School District
12.43
Seattle City Light
10.91
City of Tukwila, DNR
6.04
City of Tukwila, King County
5.41
WSDOT
3.26
Private ownership
3.25
Highline School District
3.12
King County Parks
3.02
ROW
2.48
Total
137.49
with direct restoration of land and therefore ensuring that
there is sufficient funding available to complete the work
under the umbrella of Green Tukwila Partnership. The
current property ownership breakdown is illustrated in Table
4. The above cost estimate of $5.73 million includes all lands
and it is assumed that each land owner would take on some
responsibility for securing funding for their respective sites.
Also, while different land owners would help secure funding
for their respective sites the initial implementation of the
Green Tukwila Partnership will be undertaken by the City
of Tukwila Parks and Recreation Department. Therefore,
the reminder of this cost discussion focuses on the 88 acres
of land owned and managed by the Parks and Recreation
Department. The total estimated program cost for these 88
acres of land is $3.47 million.
Estimating Program Costs
In 2005, the Green Seattle Partnership estimated the costs of
restoring 2,500 acres of forested parks for a 20 -year period. It
relied on estimates of past costs for removing invasive species,
replanting, and ongoing maintenance, as well as staff needs
and costs associated with additional fieldwork, materials,
planning, program design and management, funding de-
velopment, outreach and marketing, and field and office
overhead.
For the Green Tukwila Partnership, we used a cost model
adapted from the Green Seattle Partnership's original es-
timates (inflated to 2016 dollars), adjusted to reflect the
experience of the other Green Cities. Given that Tukwila's
park system is much smaller than Seattle's, the Green Tuk-
wila Partnership will require lower overall field costs, fewer
staff, and lower overhead. For this plan, all cost estimates and
leverage volunteer values are listed in 2016 dollars.
Using a cost model that enrolls a percentage of acres from
each tree -iage category each year over 20 years, the average
costs per acre going through the four phases of restoration
and ongoing maintenance can be calculated (Table 6).
Table 5. Average Restoration Cost per acre by tree -iage
Tree -iage Category
Cost / Acre
1
$22,000
2
$31,200
3
$37,900
4
$27,900
5
$33,500
6
$44,600
7
$31,800
8
$41,700
9
$53,700
For the Green Tukwila Partnership, the model estimates that
enrolling all 88 acres in active management will cost from
$22,000 per acre for tree -iage category 1 acres to $53,700
per acre for tree -iage category 9 acres. This estimate includes
projected program and administrative staff plus field supplies
and support, with a built -in 15% overhead on field expenses
and 7% overhead on staff time. These costs per tree -iage
category are specific for Tukwila and the length of the pro-
gram; they will need to be adjusted for use in other areas and
program durations.
The cost per acre for each tree -iage category is the total esti-
mated cost from the time it is enrolled until the end of the
plan in 2036. For example, the model projects enrolling 1.5
new acres in 2017, with a combined first -year program cost
of $77,000 for staff, field expenses, and overhead needed. As
more new acres are added each year, the cost model accounts
for various phases and maintenance of the total accumulation
of acres enrolled. The cost model also accounts for a gradual
ramping up of acres enrolled per year. New acres enrolled
per year would reach a maximum of 8 acres in year 2025,
and remain at 8 new acres per year until 2030. At which time
a gradual decrease in new acres per year would occur. All 88
acres of land would be enrolled in restoration by the end of
2032. Based on the adjusted estimates, the model forecasts
that it will cost approximately $3.47 million in 2016 dollars
to implement the Green Tukwila Partnership through 2036
to enroll all City of Tukwila Parks and Recreation Depart-
ment lands. Although the total is a high number, the cost
of effectively managing these lands solely using commercial
crews would be more expensive — and more importantly,
would not ensure long -term success from community owner-
ship in the program.
Table 6 provides a breakdown of Tree -iage category and cost
for the 88 acres of Parks and Recreation lands, and Figure 14
provides a graphic illustration of the costs of the program and
volunteer match over the 20 -year time period.
Green Tukwila 20 -Year Stewardship Plan 51
Table 6 Parks and Recreation land cost summary
Tree iage
Category
Acres
Cost / Acre
Total Cost
1
0.14
$22,000
$3,080
2
6.82
$31,200
$212,784
3
4.26
$37,900
$161,454
4
2.98
$27,900
$83,142
5
20.98
$33,500
$702,830
6
38.47
$44,600
$1,715,762
7
5.75
$31,800
$182,850
8
2.70
$41,700
$112,590
9
5.47
$53,700
$293,739
Totals
87.57
$3,468,231
$400,000
$350,000
$300,000
$250,000
$200,000
$150,000
$ 100,000
$50,000
Volunteer Match Value
Direct Program Costs
r CO 0) 0 N CO V fit)
0 0 0 0 0 0 0 0 0
N 01 N N N N N N N
Total Estimated Program and Field Costs Volunteer Match Value ($28.99/hr)
Figure 14. 20-year projections of program costs and volunteer match value
52
The remaining acres and costs are illustrated in the follwing series of
Tables 7 through 10, and are broken out by ownership. Table 10 is a
summary of all land and costs by Tree -iage.
Table 7 School district land and ROW cost summary
Tree iage
Category
1
Acres
0.00
Cost / Acre
$22,000
Total Cost
$0
2
2.57
$31,200
$80,251
3
0.00
$37,900
$0
4
0.00
$27,900
$0
5
1.11
$33,500
$37,115
6
11.50
$44,600
$513,027
7
0.00
$31,800
$0
8
0.00
$41,700
$0
9
2.85
$53,700
$152,822
Totals
18.03
$53,700
$783,215
Table 8 King County, Washington State Dept of Transportation,
Seattle City Light and Private Lands
Tree-iage
Category
Acres
Cost / Acre
Total Cost
1
1.14
$22,000
$24,974
2
0.00
$31,200
$0
3
0.00
$37,900
$0
4
1.25
$27,900
$34,873
5
1.57
$33,500
$52,626
6
0.15
$44,600
$6,827
7
3.89
$31,800
$123,702
8
0.00
$41,700
$0
9
12.44
$53,700
$668,185
Totals
20.44
$911,188
Green Tukwila 20 -Year Stewardship Plan 53
Table 9 Other jointly managed lands cost summary
Tree iage
Category
1
Acres
0.00
Cost / Acre
$22,000
Total Cost
$0
2
0.00
$31,200
$0
3
0.00
$37,900
$0
4
0.00
$27,900
$0
5
0.00
$33,500
$0
6
9.42
$44,600
$420,040
7
0.00
$31,800
$0
8
0.00
$41,700
$0
9
2.03
$53,700
$108,836
Totals
11.44
Totals
$528,876
Table 10 All lands cost summary
Tree-iage
Category
Cost / Acre
$22,000
Total Cost
$27,940
1
1.27
2
9.39
$31,200
$293,035
3
4.26
$37,900
$161,454
4
4.23
$27,900
$118,015
5
23.66
$33,500
$792,571
6
59.55
$44,600
$2,655,930
7
9.64
$31,800
$306,552
8
2.70
$41,700
$112,590
9
22.79
$53,700
$1,223,805
Totals
137.49
$5,691,892
54
Resource Objective 1: Continue current City funding
and build capacity for future growth
During the program's first five years, the cost model proj-
ects an estimated cost of $77,000 in 2017, which grows to
$260,000 in 2030 (the highest annual amount). Additional
funding sources will need to be secured to bring all 138 acres
identified in the forest assessment into restoration by 2036.
Resource Objective 2: Leverage City funds through
partnerships and develop long -term funding to
support the work
Forterra and EarthCorps are already active partners with
the City, working on restoration projects within the Green
Tukwila project area. By bringing in additional partners,
strengthening partner relationships, and seeking outside
funding to support partners working together, City funds
will be leveraged to achieve this plan's outcomes.
Resource Objective 3: Provide sufficient staff and
resources to support fieldwork, volunteer outreach
and management, community engagement, and
program administration
Volunteer Management
Currently, volunteers are providing approximately 3,000
hours each year supporting the type of stewardship work in
Tukwila's parks and natural areas that the Partnership seeks
to expand. While these are not all specific forest - restoration
hours, the number serves as a baseline for similar volunteer
activity.
The City of Tukwila does not currently have a dedicated
volunteer- coordinator position who could manage Green
Tukwila volunteers, although it does have staff involved
in various relevant positions, including critical -area man-
agement, outreach, and community events. As the Green
Tukwila Partnership approaches its goal of 4,000 volunteer
hours at its peak in 2021, experience suggests that at least
one employee will need to be dedicating 1560 to 2080 hours
annually for managing and coordinating restoration volun-
teer efforts across the program. This position would track
volunteer time, recognize volunteer achievements, and recruit
additional volunteers, and could also run the Forest Steward
Program, discussed below. Forterra will initially play a major
role in volunteer management, conducting regular volunteer
events to help incorporate the experience gained through
implementing the other Green City Partnerships. As a
structure becomes established, the City can take the lead in
volunteer management internally or continue to contract
these services with a professional provider.
Forest Steward Program Management and Training
At its inception, the Green Tukwila Partnership will al-
ready include trained site Stewards supported by Forterra
and EarthCorps at several sites within the project area. The
Green Tukwila Partnership will continue to recruit and train
additional volunteers who are interested in a higher level of
commitment than attending occasional staff -led volunteer
events. These Stewards will allow the Partnership to in-
crease community leadership on the ground and therefore
its capacity to reach more restoration sites. Stewards will
lead volunteer events, create work plans, track restoration
progress, and apply for small grants to manage their sites.
This program will also keep regular volunteers interested
by providing a challenging and diverse array of work, and
increased ownership of the results.
The success of the Steward Program is dependent upon a
staff member being able to coordinate the program, includ-
ing training new stewards, working with them to develop
site plans, providing support and encouragement, coordi-
nating their efforts with other city staff, and keeping track
of their accomplishments in relation to Partnership goals.
These duties are estimated to take 520 to 1040 hours an-
nually. For consistency in program implementation and
volunteer support, it is strongly recommended this role be
incorporated into the duties of the volunteer coordinator
mentioned above.
Outreach and Education
Staff time devoted to education and outreach will be critical
in helping increase volunteer capacity to 4,000 hours by
2021 and hosting many appreciation and public- engage-
ment events each year. Reaching the broader Tukwila public
will require a staff person to devote a portion of time to
Green Tukwila Partnership outreach and education. Forterra
can help fill some of this role during the program's first year,
or longer as needed and if resources allow. The City will also
Green Tukwila 20 -Year Stewardship Plan 55
coordinate with the Communications Manager, within the
Mayor's Office, to take advantage of outreach opportunities
that exist through its publications and products.
Communications and marketing are linked to the duties
of volunteer management, outreach, and education. This
work will be started by Forterra for the first two years of the
program and includes creating and implementing a commu-
nications and marketing plan. This will help the Partnership
increase visibility and recruit volunteers, as well as increase
the potential for generating additional program funding by
reaching a wider audience.
Field Restoration
Current City of Tukwila staffing alone cannot meet the
management needs of restoring and maintaining all 138 acres
by 2036. Through the Green Tukwila Partnership, partner
agencies and community leadership will play a major role in
filling the gap. Planning and Urban Environmental Special-
ist staff will continue to play a lead role in evaluating and
managing Tukwila's forested parks and natural areas, espe-
cially as more volunteers are brought in to help restoration
work. Besides these staff members, the Parks and Recreation
Department may contract with skilled field crews for some
fieldwork on sites that are not appropriate for volunteers, and
partner agencies will either use their own crews or contract as
well. In the first couple of years, training in restoration best
56
management practices and volunteer management will help
ensure that all staff and contractors are up to speed with the
same techniques and approach that are being taught to forest
stewards, in addition to crew - specific practices that volun-
teers are not permitted to perform. This coordination will
be one of the functions of the Green Tukwila Management
Team.
Program Administration and Fund Development
Designated City staff will be needed to oversee and adminis-
ter the program. This includes establishing annual program
work plans and communicating with various City commis-
sions and City Council so they remain informed about the
programs success and any challenges along the way. This also
includes development and management of funding. Stable
funding is crucial to supporting the Partnership's efforts. The
role may be large if many small funding sources are com-
piled, or less intensive if funding is derived from one or a few
larger sources. This role may incorporate grant writing.
Resource Objective 4: Coordinate efforts by partner
staff and volunteers to maximize joint success and
share resource
Working across ownership boundaries, partner agencies —
including both landowners such as the City of Tukwila and
Everyone Pitching In
If every Tukwila resident contributed just a bit more than 4 hours, we would achieve
our goal of restoring and maintaining Tukwila's forested parks and natural areas and
open spaces. That's just one work party during the program's 20 years. Many hands
make light work!
= 71,500
Seattle City Light, and partners such as Forterra, EarthCorps,
and others helping to implement the work outlined in this
plan — will need to work together. All partners will need to
communicate and coordinate their efforts so the work on the
ground and in the community is conducted in a way that
addresses needs in a comprehensive, rather than piecemeal,
manner. In order to take advantage of opportunities to share
resources and avoid duplicating efforts, all active partners will
meet regularly as a Management Team. The Management
Team will hold quarterly meetings in the first year of the
Partnership, and may meet more often and /or form commit-
tees to address certain topics as the Partnership grows. The
Management Team will also be in communication with other
relevant local groups, such as the Duwamish Alive Coalition,
Green River Coalition, and Green Cities Network.
Resource Objective 5: Deploy skilled field crews as
appropriate, prioritizing training crews and job -
skills- development programs available to Tukwila
residents
Professional crews will be needed for priority sites that lack
sufficient volunteer support or sites with difficult conditions
that are unsafe or otherwise inappropriate for volunteers.
Some sites containing extreme invasive plant infestations,
steep slopes, riparian areas, and wetlands may be better suited
to skilled field crews.
The Partnership will seek to contract with organizations that
focus on forest - habitat management, and will prioritize those
that provide training and job - skills development to local resi-
dents, especially youth. The following activities will support
this objective:
• City and partner staff will continue to work on key
management efforts, volunteer support, and training for
Stewards to increase community capacity.
• Nonprofit and training crews (such as Washington
Conservation Corps, Student Conservation Association,
EarthCorps, Duwamish Valley Youth Corps, and DIRT
Corps) will have priority to be hired, as needed, for
fieldwork at difficult sites and occasionally for volunteer
management at large events, given their expertise. Crews
that offer jobs and job training to Tukwila residents will
be further prioritized.
• Private landscaping and habitat - restoration companies
(commercial crews) will be hired for highly technical
projects as budget and need dictate.
Resource Objective 6: Increase volunteer
engagement to leverage support from the
community
Over 20 years, our goal is for volunteers to provide more
than 71,500 hours, valued at $2 million, based on the 2015
Independent Sector valuation of a volunteer hour at $28.99
in Washington State. To put this number in perspective, if
every Tukwila resident contributed just four hours during the
entire 20 -year program, the plan would achieve its commu-
nity- engagement goals. If every resident contributed just
Photo by McRob
Green Tukwila 20 -Year Stewardship Plan
57
eight hours over the entire 20 -year program, the Partnership
would double its goals and leverage significantly more toward
restoration and management of Tukwila's parks and natural
open space.
To meet the needs of all volunteers, the Green Tukwila
Partnership will provide several ways in which they can
participate. A variety of large volunteer events can be held
in conjunction with community groups and businesses.
Community events aimed at promoting more of a connec-
tion between local residents and their urban environment
will hopefully encourage more people to take an interest
in stewardship efforts. The Steward Program can support
community leaders in developing and coordinating regu-
lar work parties that volunteers can attend as often as they
wish. Active management at these sites will range from large
invasive - plant - removal projects and planting native species to
monitoring past restoration.
Increased levels of volunteerism will be encouraged. Volun-
teers who participate in one -day events with a business or
community group will be invited to continue their partici-
pation in ongoing work parties. Frequent volunteers may
be interested in becoming Stewards so as to increase their
involvement. To do this, there will be a need to keep existing
volunteers motivated by showing them how their efforts, in
concert with those of many other volunteers, have a signifi-
cant impact in maintaining and restoring Tukwila's forested
parks.
The Partnership provides opportunities for individuals of
varying physical ability and time commitment to get in-
volved. There are numerous volunteer activities for those
who are uninterested or unable to participate in physical
fieldwork, or who require a more flexible schedule, including
photography, database and administrative work, publicity
and marketing, fund - raising, sponsor recruitment, com-
munity event support, and bringing snacks and beverages to
work parties.
In addition to encouraging current volunteers, new volun-
teers can be recruited through community outreach that
emphasizes their critical need and the important role they
play in effective management. Partnerships with community,
58
youth groups, businesses, and schools can also be used to
introduce new volunteers to the program.
Diversity within the Partnership will strengthen work efforts
and build community. An important component of outreach
efforts will involve contacting communities that have not
traditionally participated in environmental restoration or
stewardship. Outreach to these communities can be increased
by working with local groups, youth organizations, schools,
and businesses, looking for ways to collaborate on projects
that offer mutual benefit and culturally relevant ways to
participate. Informational signs at park sites can be posted
describing the work under way and inviting participation.
The existing partnership between the City of Tukwila and
the Tukwila School District can be strengthened to provide
opportunities for students who want to complete commu-
nity- service requirements for graduation, and participate
in restoration projects on school grounds within the Green
Tukwila project area.
Resource Objective 7: Support local businesses
The work of the Green Tukwila Partnership offers many op-
portunities to support the Tukwila economy and local busi-
nesses within the city in the following capacities:
• Professional field crews for on- the - ground restoration
and stewardship
• Local businesses to provide food
and refreshments for volunteer and other community
events
• Graphic designers, marketing and outreach specialists,
and other professionals to help with promotion of Part-
nership activities
• Photographers to help document events
• Skilled professionals to offer training to staff and volun-
teers in a wide variety of topics, from plant identification
and ecology to ethnobotany, community engagement,
and grant - writing
• Engagement opportunities, including corporate dona-
tions and volunteering, for businesses to get their name
out in front of the community and offer team - building
activities.
VI. ADAPTIVE MANAGEMENT
The Green Tukwila Partnership's primary goal is
to reestablish and maintain healthy, sustainable
natural open spaces. The Partnership is an inten-
sive, one -time intervention to restore the health
of Tukwilas native habitats through community
action, volunteer effort, and strategic restoration
planning. After 20 years and restoration of the
projected 138 acres in the program, labor and
funding needs can be reduced to a maintenance
level, but funding needs will continue to exist.
The goal of a healthy natural forest or natural -ar-
ea park can be achieved only by careful manage-
ment of resources.
Urban forests and public natural areas are
complex ecosystems influenced both by natural
factors and the human systems that surround them. These
human systems that impact and ultimately must care for
these ecosystems are equally complex. Any strategy to restore
and maintain forested parklands must systematically ad-
dress all the factors that affect the health of those lands. In
response to this complexity, an adaptive management model
has been developed.
Photo byMcRob
Adaptive management systematically improves management
policies and practices. It is a repeating cycle of six steps:
problem assessment, strategy development, implementation,
monitoring, evaluation, and strategy adjustment (see Fig-
ure 15). Once an evaluation is complete, new information
gathered from monitoring is used to reassess the problem and
develop new strategies as needed. Then implemen-
tation, monitoring, and evaluation occur, and the
cycle begins again.
This section describes how the Partnership will
apply adaptive management and the Balanced
Scorecard approach to track and monitor progress,
distribute resources, and report on the Partner-
ship's success. The Balanced Scorecard approach to
strategy development and monitoring helps assess
all aspects of the program (fieldwork, community,
and resources) necessary to reach the goal of enroll-
ing all 138 acres in restoration by the end of 2036.
Simply monitoring the outcomes of fieldwork
would not allow staff to anticipate problems and
make adjustments to other parts of the program.
The Balanced Scorecard allows staff to track the
resources and community support necessary for ac-
complishing the fieldwork.
Define
Strategy
Figure 15. Adaptive management framework cycle
Green Tukwila 20 -Year Stewardship Plan 59
MEASURING SUCCESS
Two types of information will help in analyzing the Green
Tukwila Partnership's effectiveness: program monitoring and
field monitoring. Monitoring allows for improvement in
Partnership program design and performance by measuring
the effectiveness of strategies and techniques used. The results
of monitoring are fed back into Partnership planning and
methodology to increase effectiveness. Monitoring and evalu-
ation will also provide accountability to funding sources and
supporters, and help ensure that goals and benchmarks (see
Appendix J) are met.
Table 8 illustrates the Balanced Scorecard for the four pri-
mary program elements of implementing the 20 -year plan:
fieldwork, community, resources, and administration. By
measuring progress toward each objective, one can assess the
effectiveness of the strategies described in the Implementa-
tion section. The effectiveness of program strategies needs
to be tracked throughout the life of the plan, and, through
adaptive management, adjustments made when necessary.
60
Photo by McRob
PROGRAM EVALUATION
At the close of each year, Green Tukwila Partnership staff
will continue to collect data on Balanced Scorecard measures
and track progress toward the annual work -plan goals and
benchmarks. Data - management systems will be developed
to record information pertinent to these measurements
Photo by McRob
throughout the year so that progress can easily be summarized
at year's end.
FIELD MONITORING
As the restoration and maintenance program proceeds, rou-
tine monitoring of restoration sites will continue to be con-
ducted to track the condition and health of restored sites and
gauge progress. Success will rely on developing and refining
effective strategies to remove and control invasive plants.
To monitor fieldwork, new acres will be tracked as they are
brought into active restoration and mapped in GIS. Volunteer
and skilled- field -crew time will be devoted to revisiting sites
that have been previously worked on and assessing their ongo-
ing needs as they move through the four phases of restora-
tion. One component of monitoring is to track plant survival
rates. Plant- survivorship thresholds are outlined in site -level
stewardship plans and may vary depending on site conditions
or habitat type. These forests and natural areas will always be
subject to pressure from their surroundings. Although the
work needed decreases dramatically each year that an area
goes through the program, Phase 4 of restoration continues
indefinitely.
As the Partnership enrolls more acres in restoration, track-
ing can become complicated. Managing data entry and
paperwork as the program grows has proven to be expensive
in other Green Cities. The Partnership is in the process of ad-
dressing this issue and investigating database tools to stream-
line data - management processes.
RESOURCE DISTRIBUTION
It is assumed that Green Tukwila Partnership funding will
continue to be housed entirely within currently active part-
ners — the City of Tukwila, Forterra, and EarthCorps — for
at least the first year of the program. After that, staff from the
City and partner organization will continue to oversee pro-
gram funding and work toward generating additional funding
(both from City and non -City sources) and donations from
outside sources throughout the duration of the Partnership's
20 -year span. The Partnership will allocate funds for the three
program areas — community, fieldwork, and resources — in
proportions that will change during the course of time to help
ensure that the program's basic goals are achieved. As it grows
from single -site efforts to a systemwide program, the emphasis
will shift from funding program development to fieldwork
support.
At the front end, resources will be directed toward recruiting
and supporting Stewards, along with demonstrating on -the-
ground results and success in the field, and hosting highly
visible community events that foster engagement with Green
Tukwila sites. These activities will ramp up during the first
five years (2017 -2021) as volunteer efforts grow. Once a
strong volunteer program is established, some resources can
shift to provide more field support for restoration projects.
As funding allows in the future, the field- management bud-
get can expand from funding Partnership staff time and sup-
porting volunteers to include additional skilled field crews.
Implementation tools such as BMPs will be incorporated
into their work.
As visibility and recognition increase, increased levels of pub-
lic and private funding can materialize and support increased
volunteer participation. The role of volunteers will continue
beyond 2036, since parks and natural areas will need ongoing
volunteer support and stewardship.
REPORTING AND KNOWLEDGE
SHARING
The Green Tukwila Partnership's progress will be reported an-
nually to the Tukwila City Council, Tukwila Parks Commis-
sion, partners, Stewards, volunteers, and the public. Annual
work plans will be adjusted in response to available funding,
monitoring results, and emerging knowledge of successful
restoration techniques.
Partnership staff will utilize creative outreach strategies, and
network with regional restoration groups, which will provide
an opportunity for staff to share information and learn from
other agencies. As a member of the Green Cities Network,
the Green Tukwila Partnership will have opportunities to
share successes and challenges with other cities (Seattle,
Tacoma, Kirkland, Redmond, Kent, Everett, Snoqualmie
and Puyallup) that are dedicated to a similar goal and vision.
Written materials, including this 20 -year plan, will be posted
on the Green Tukwila Partnership website (www.greentuk-
wila.org), and all parties using these resources will be given
the opportunity to provide feedback on the Partnership's
methods and materials.
Green Tukwila 20 -Year Stewardship Plan 61
Balanced Scorecard
OBJECTIVE
MEASURE
Restore and maintain 138 acres of parks and natural areas by 2036
# of acres in restoration to annual goal
FIELDWORK: All 138 acres are restored by 2036
Evaluate
Evaluate conditions and prioritize sites for restoration
using tree -iage model
# sites evaluated, prioritized
Plan
Develop annual work plan for each active Park
Annual work plan completed identifying active management
sites at each active Park
Implement
Implement restoration projects optimizing ecological
function, using the 4 -phase approach
• # of acres entered into active management
• Best practices evaluated annually and updated as needed
Monitor
• Establish monitoring program
• Monitor and maintain sites over the long term
• Annual monitoring report
• # of acres entered into Phase -4 work
• Maintenance is performed as indicated
COMMUNITY An informed, involved, and active civic community supports the Green Tukwila Partnership.
Residents
Educate and engage community about problem and
solution through Green Tukwila Partnership
Outreach and education program materials developed and
distributed
Community supports and desires active management of
forested parklands through widespread understanding of
the issue and support of the Partnership as a solution
• % of residents volunteering each year
# of return volunteers
Encourage businesses to contribute to program goals
• # of businesses supporting program through sponsorship,
in -kind contributions, or volunteer events
• # of businesses supporting volunteer events
Volunteers
Engage youth and community organizations in
restoration and monitoring
• # of groups participating in events
• # of hours contributed
Recruit and train forest stewards in volunteer
management and BMPs
• # of active forest stewards
• # of forest steward events
Demonstrate appreciation for volunteers and seek input
into program
• # of volunteer suggestions implemented
• # of volunteer recognition activities
RESOURCES: Sufficient resources are available to actively manage sites and provide long -term maintenance.
Financial
Continue current municipal funding
$ budgeted and sourced to meet management requirements
Develop long -term, stable public funding source
Mechanisms in place by 2027 sufficient to meet need
Paid Staff&
Labor
Provide sufficient staff to support fieldwork, volunteer
management, and Partnership programs
• # staff /crew dedicated to supporting the program
• % of requests for crew /staff assistance completed
Deploy skilled field crews for priority sites lacking
volunteer support or sites with difficult conditions
• # of acres in restoration due to crew /staff
• % of skilled field crews trained in BMPs
Volunteer
Labor
62
•
Increase number of individual volunteers as well as
the overall number of volunteers
Increase productivity by providing support and
materials to volunteers
• # of hours to annual goal
• Estimated value of volunteer contribution
• $ and hours /acre enrolled
• Staff cost per volunteer hour
• # of tool /material requests processed
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Green Tukwila 20 -Year Stewardship Plan
65
XIII. APPENDICES
APPENDIX A. MAPS OF TREE -IAGE CATEGORIES PER SITE: OVERVIEW
AND INDIVIDUAL SITE MAPS
Key to Individual Sits Maps
Site Name Map Number
Dswarnnxh Gardena 1
DLiwarnish HAI Preserve 2
f]trvamislt Park 2
Duwarnislt Restoration
Challenge
Fort Dent Business Loop
Fort Dent Park
Foster Fire Station
Faster Golf Links
Foster HO School &
Showalter Middle Schoci I 3
Foster Memorial Park 4
Faster Point lookout Parse 4
Gilliam Creek Detention Poled 5
Green River and Interurban
Trail Junction 6
Hazelnut Park
Fire Station 52 4&6
Interurban Hill Sate 4 & 6
Lookout Park 4
Macadam Rd. 5, Site 5
Macadam Wetlands
Winter Garden 4
Nelsen Site 6
North Wind's Weir 1
P.17 Pond 7
Pamela Drive Site 4
Raverton Creek 2
Rnverton Mini Parse 3
Riverton Park 3
5. 1 15th 5t. Riverbank 2
S. 125th Sr_ Site 2
S. 1413th St ROW &
Riverbank Parcels 4
S I52nd ROW 5
Di warnith Hrll 2
Ryan Creak 3
Ryan Hill 2
Siccartl. Site 2
Southgate Park 3
5trander ROW 6
Thorndyke Elementary
T1B & S. 1134th 5t 3
2
6
6 {Part4)
3
4
r.
I°
Key to Individual Sim Maps
tite
42nd Ave 5.1
S. 1 1 5th St_, Riverbank
57th Ave_ S. Mini Park
54th A. S. Trail
Allentown Fire Station
Bicentennial Park
Cascade View
Community Park
Cascade View Elementary
Cull Moses Memorial Park
Chinook Wind
Chnstensorl R. Sete
City Hall Campus
Catch Park
Crestview Park
Crystal Springs Park
lion Number
2
4
4 {part 6)
2.
6
3
3
6
6
2
5
5
N
L
s:gc Mimic
Trail I
Trail 3
Trail 4
Tukwila. Community Center
Tukwila Elementary School
Tukwila H11I Reservoir
Tukwila Hill Site
Tukwila Park
Tukwila Parkway Site
Tukwila Pond Park
Tukwila Pool MPD
West Val ley Rner#a:nk
Map h.Inner
6 (part 4)
6
6
2
6
6
6
6
6
7
3
7
.nap e.eeeed it fornitlI .r, re. hit w.et eh. Leer .I T... mi.
66
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0
I 12ill Sr
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Duwamish
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-
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2
8
9
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Green Tukwila 20-Year Stewardship Plan 67
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9
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at riglit for
more detail
Allentown
Fire
Station
•S. 115th
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Riverbank S 115th St
Riverbank
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Creek
0 500
l l
42nd Ave S/
5 115th St
Riverbank
42nd Ave S/
S 115th St
Riverbank
Duwamish
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rl,rl:.,
Tukwila
Community
Center
Map
Duwamish Hill Preserve
S. 125th
Street
Site
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D
Duwamish Restoration
Challenge
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Elementary
o co
F i
Ti-* 1ge CArtesarie:
8
6
9
LOW I1!m41M POOH
THREAT
Cascade View
Community Park
Hahiral Management Unit. (HMV)
hnundanns are datinnataxl hjr a thin
whim each ) MU o i this map
is pnrtrard *nth a MI their
correjparrrling Ian the' Tre ige
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and ii IibcI d with an .ientlfitataori
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Park
Library
Foster High School
and
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ZatiOt
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Pool
MPD
Foster
Fire Station
#54
7rlt*- Ia;FIr h ti '1,.n.14r:;:-•,I Inr tltebuf 2501
Green Tukwila 20 -Year Stewardship Plan
69
Map 4
tits -� IPfllt
57th Ave 5
Mini Park
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i E i
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Ind ra labr ed With an ldanmlriutiOn
latter uriepan to that park or hue
Ur irtcorpc wtect
KWid Counti
Foster
Golf Links
Southwest
Kin; County
Chamber of
Commerce
l
Macadam
Wetlands
Winter
Garden Hazelnut Park
59th
Ave 5
Trail c
Fort Dent Park
Shown in full on Map fa
Interurban
Hill Site
Acativ
Fire Station 52
map treaied -br Fail €B PJr - .. =" Tulwils
70
Trail 1
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Tree laic !hetd astcssmcn: conitu.:: a rlcan 'Forest !Manatemena, Int., Ctcrnt:er 201-5
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Road S
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152nd Thorndyke s 1340 51
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Gilliam Creek
Detention Pond
c
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Park
mip cfc,r,3 1=1. FORTERRA 47.'1-Iraq
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1
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9
LOW MIEHLIPI 141(111
THREAT
Habitat Mn Unit ML.I) tokindar lei are delineated by a chin whim outline.
Each HMIU! th I map i pertraytA wmit A MI Cdtrii oorretponding the/bee-late
Category mat. test cba ra [Lenin r and k labeled with an idendicadon letter
Unique to th ar. pi k or lite.
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Green Tukwila 20-Year Stewardship Plan 71
59th Ave 5-
Trail A
Shown in fun c Interurban
an Map 4
Hill Site
Acaderny
Sdianis
Map 6
Hazelnut Park &
Fire Station 52
Tukwila
Elementary
School
Fort Dent
Park
Trait 3
Tukwila
Hill
Reservoir
In
- I 1
1 A TijkWila
Hill 11-2
Site
Fort Dent
Business
Loop
Trail 4
Green River and 3
interurban Trail
Junction iffi
City Hall
Campus
navy 11
A
Tukwila
Park
--- Tukwila
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Iii
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THREAT
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Nelsen
Historica
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Christenson Rd
Site
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Map 7
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Park
International' 1
Academy King
of Design County
Housing
Authority
Administration
UpJAJILI J. Or
Tree.iage Catigorlon
1
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THREAT
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Green Tukwila 20-Year Stewardship Plan 73
APPENDIX B. FOREST LANDSCAPE ASSESSMENT TOOL (FLAT) FLOWCHART
FOR HABITAT COMPOSITION VALUE
74
<2 native tree canopy cover
w
0
re
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0
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1
APPENDIX C. MANAGEMENT -UNIT ACRES PERTREE -IAGE CATEGORY
Site Name
1
2
3
Tree -iage Category
4 5
6 7
8
9
Acres
per site
42nd Ave S/S 115th St Riverbank
4.3
4.3
57th Ave South Mini Park
0.1
0.1
59th Ave STrail
1.1
1.1
Allentown Fire Station #53
1.5
0.6
2.1
Bicentennial Park
0.1
0.1
0.3
Cecil Moses Memorial Park
0.6
0.6
Chinook Wind
1.7
1.7
Christenson Rd Site
1.4
1.4
City Hall Campus
0.3
0.3
Codiga Park
1.6
2.0
3.6
Crestview Park
2.6
0.6
3.1
Crystal Springs Park
9.1
1.0
10.2
Duwamish Gardens
1.8
1.8
Duwamish Hill Preserve
0.1
0.1
1.4
2.7
0.3
3.9
0.7
9.3
Duwamish Restoration Challenge
1.2
2.0
3.2
Fort Dent Business Loop
4.0
4.0
Fort Dent Park
3.1
3.1
Foster Golf Links
3.3
2.9
6.2
Foster High School and Showalter Middle School
3.6
3.6
Foster Point Lookout Park
0.2
0.2
Gilliam Creek Detention Pond
1.9
1.9
Interurban Hill Site
1.7
1.7
Macadam Rd S Site
0.5
0.9
1.4
Macadam Wetlands &Winter Garden
2.0
6.4
8.4
Nelsen Site
2.0
2.0
North Wind's Weir
0.6
0.6
P -17 Pond
5.4
5.4
Pamela Drive Site
0.7
0.7
Riverton Creek
0.4
0.4
Riverton Park
0.6
0.6
S 115th Street Riverbank
0.3
0.3
S 152nd ROW
0.8
0.8
S. 125th St Site
0.2
0.2
S. 140th St. ROW & Riverbank Parcels
0.8
0.8
SCL - Duwamish Hill
2.2
0.4
2.5
SCL - Ryan Creek
1.6
1.7
3.2
6.5
SCL - Ryan Hill
1.8
1.8
Siccardi Site
0.9
0.9
Southgate Park
11.6
11.6
Green Tukwila 20 -Year Stewardship Plan 75
APPENDIX C. CONT.
Site Name
1
2
3
Tree -iage Category
4 5 6 7
8
9
Acres
per site
Thorndyke Elementary
5.0
5.0
TIB & S 130th St
0.2
0.2
Trail 1
0.9
0.9
Trail 3
0.8
0.8
Trail4
0.8
0.8
Trail Junction: Green River and Interurban
0.2
0.2
Tukwila Community Center
0.8
0.8
Tukwila Elementary School
0.4
2.8
3.3
Tukwila Hill Reservoir
0.2
0.2
Tukwila Hill Site
1.9
0.1
2.1
Tukwila Park
4.3
4.3
Tukwila Parkway Site
0.9
0.9
Tukwila Pond Park
6.3
6.3
West Valley Riverbank
3.3
3.3
Acres per tree -iage category
1.3
9.4
4.3
4.2
23.7
59.5
9.6
2.7
22.8
137.5
76
APPENDIX D OVERSTORY SPECIES DOMINANCE BY MU ACRES
Scientific name
Common name
Primary species
by MU acres
Secondary
species by MU
acres
Tertiary species
by MU acres
Acer macrophyllum
Bigleaf maple
43.2
26.6
8.8
Alnus rubra
Red alder
2.0
54.5
21.2
Sequoia sempervirens
Coast redwood
0.5
5.4
0.4
Betula papyifera
Paper birch
0.9
Betula pendula
Silver birch
0.2
Fraxinus Iatifolia
Oregon ash
0.5
Pinus contorta
Shore pine
0.1
0.2
0.6
Picea sitchensis
Sitka spruce
0.9
Populus balsamifera
Black cottonwood
57.9
8.6
17.1
Prunus emarginata
Bitter cherry
0.8
1.8
4.4
Pseudotsuga menziesii
Douglas -fir
7.6
10.8
20.7
Rhamnus purshiana
Cascara
3.3
Salix lucida
Pacific willow
1.7
0.9
9.0
Salix sitchensis
Sitka willow
3.0
5.1
0.8
Arbutus menziesii
Pacific madrone
0.3
Thuja plicata
Western redcedar
0.2
0.9
18.3
Green Tukwila 20 -Year Stewardship Plan 77
APPENDIX E. UNDERSTORY SPECIES DOMINANCE BY MU ACRES
Scientific name
Common name
Primary
Secondary
Rubus spectabilis
Salmonberry
29.3
8.1
Corylus cornuta
Beaked hazelnut
19.0
8.4
Grass species
Grass
17.3
2.2
Salix lutea
Yellow willow
14.2
8.1
Symphoricarpos albus
Snowberry
12.3
18.1
Cornus sericea
Red osier dogwood
11.3
22.6
Spiraea douglasii
Hardhack; spiraea
7.2
Gaultheria shallon
Salal
3.1
Pteridium aquilinum
Bracken fern
2.8
Juncus effusus
Soft rush
1.7
Polystichum munitum
Sword fern
1.3
15.3
Salix scouleriana
Scouler's willow
0.8
3.1
Holodiscus discolor
Oceanspray
0.6
0.2
Malus fusca
Pacific crabapple
0.6
Oemleria cerasiformis
Indian plum
0.4
20.2
Equisetum fluviatile
Swamp horsetail
0.3
Physocarpus capitatus
Pacific ninebark
0.2
3.1
Mahonia nervosa
Dull Oregon grape
0.1
6.2
Rubus ursinus
Trailing blackberry
2.0
Willow species
Willow (unknown sp.)
1.7
Mahonia aquifolium
Tall Oregon grape
0.6
78
APPENDIX F. INVASIVE SPECIES OCCURRENCES BY MU ACRES
Scientific name
Common name
MU acres
% of project area
Rubus armeniacus
Himalayan blackberry
121.8
88%
Hedera helix
English ivy
70.0
51%
Phalaris arundinacea
Reed canary grass
57.1
41%
Prunus laurocerasus
Cherry laurel
38.5
28%
Calystegia sepium
Hedge bindweed
28.4
21%
Polygonum x sp
Knotweed
14.4
10%
Cytisus scoparius
Scotch broom
12.9
9%
Ilex aquifolium
English holly
11.9
9%
Crataegus monogyna
English hawthorn
11.0
8%
Tanecetum vulgare
Common tansy
8.6
6%
Geranium robertianum
Herb Robert
1.9
1%
Grass species
Grass
1.8
1%
Phragmites australis
Common reed
1.7
1
Robinia pseudoacacia L.
Black locust
1.0
1%
Cirsium arvense
Canada thistle
0.1
<1%
Solanum dulcamara
Bittersweet nightshade
0.1
<10/0
Green Tukwila 20 -Year Stewardship Plan 79
APPENDIX G. PUBLIC INPUT
The following answers provide a summary of the public input recieved from members of the community.
Information was solicited in person at various public venues as well as online.
When you spend time outside, what do you like to do?
by'
Percent of Responses
67%
Green River Trail
Relax
Enjoy nature
66%
Spend time with friends and family
65%
Exercise
60%
Play sports and games
35%
Picnic and BBQ
34%
Spend time alone
27%
Fish
12%
Walk dogs
3%
Garden
2%
Identify wildlife and native flora
2%
Bike
1%
What is your favorite Tukwila Park or place to go outside?
Park or Natural Area
Number of Responses
12
Green River Trail
Duwamish Hill Preserve
12
Duwamish Park
6
Tukwila Community Center
6
Riverton Park
6
Fort Dent
5
Crestview Community Park
5
Macadam Winter Garden
4
Foster
4
Cascade View Community Park
4
Tukwila Park
3
Crystal Springs
3
Bicentennial Park
2
North SeaTac Park
1
Codiga Park
1
Namaste Garden
1
Christensen Trail
1
80
APPENDIX G. CONT.
Where do you typically learn about community news and events?
Response
Number of Responses
Tukwila Reporter
16
Word of mouth /neighbors /coworkers /landlord
16
Online
13
Email
13
Social media (Facebook and Twitter)
12
Hazelnut
12
Fliers around town (library, coffee shops, community center, in parks)
12
Neighborhood listsery
10
Through the School District
5
City website
4
Mail
3
Parks and Rec Guide
2
Next Door
2
Forterra
2
Tukwila Talk
1
Text message
1
73% of the survey takers live in Tukwila. The following Tukwila neighborhoods were represented:
Tukwila Neighborhood
Number of Responses
Allentown
13
Riverton
11
Tukwila Hill
8
McMicken
8
Foster
6
Cascade View
4
Thorndyke
1
Poverty Hill
1
Tukwila South
1
Green Tukwila 20 -Year Stewardship Plan 81
APPENDIX G. CONT
What would make volunteering easier or more appealing to you?
Response
Number of Responses
Easy parking options
19
Clear communication about events
10
Easy access from public transportation
8
Transportation from a central location
7
Feel like you are making a difference
6
Childcare provided
6
A social atmosphere at volunteer events
4
Volunteer opportunities on the weekend
3
Volunteer opportunities on weekdays
3
Knowing that volunteer work will be maintained
3
Consistent scheduling for volunteer opportunities
2
Different types of volunteer opportunities
2
Volunteer opportunities after work hours
2
Informing the school district about opportunities
2
Not enough time to volunteer
2
Food and coffee at volunteer events
1
Volunteer opportunities held in my neighborhood
1
Kid - friendly activities
1
Volunteer opportunities during lunch hours
1
Volunteer event reminders
1
Interpreters available at volunteer events
1
Volunteering with coworkers at a work- sponsored event
1
Ongoing volunteer opportunities with no set schedule
1
82
APPENDIX G. CONT.
Of the 83 individuals surveyed, the following percent identified as:
Race
Percent of Responses
White or Caucasian
67%
Asian/ Pacific Islander
14%
African - American or Black
11%
Latino
4%
Native American
2%
Other
1%
Chose not to say
6%
Age range of the 83 individuals who responded to the survey:
Under
Age Range
18
Number of Responses
2
18
-24
4
25
- 34
11
35
- 44
20
45
-54
20
55
-64
14
65 and older
7
Chose not to say
5
Survey answers were collected online and in- person. Of the 83 surveys filled out, the responses
were collected from the following sources:
Survey Source Number of Responses
Online Survey
43
Outreach Tabling at Public Events
37
Green Tukwila 20 -Year Stewardship Plan 83
APPENDIX H. SHORT - AND LONG -TERM STRATEGIC PLAN AND
BENCHMARKS
Short -Term Strategic Plan Benchmarks 2013 -2017
in
w
2017
2018
2019
2020
2021
Develop stewardship
plans for two priority
sites
Continue work on 1.5
previously enrolled
acres
Continue work of 3.5
previously enrolled
acres
Continue work on 6.5
previously enrolled
acres
Continue work on 9.5
previously enrolled
acres
Enroll 1.5 acres in
initial restoration
Enroll 2 new aces
into restoration
Enroll 3 new aces into
restoration
Enroll 3 new acres
into restoration
Enroll 4 new acres
into restoration
Develop tracking
plan
Develop stewardship
plans for any new sites
Develop stewardship
plans for any new
sites
Develop stewardship
plans for any new
sites
Develop stewardship
plans for any new
sites
COMMUNITY
Recruit and manage
3,000 volunteer
hours
Recruit and manage
3,000 volunteer hours
Recruit and mange
3,200 volunteer hours
Recruit and manage
3,500 volunteer hours
Recruit and manage
3,800 volunteer
hours
Establish a
stewardship
program
Recruit 5 new stewards;
support all active
stewards
Recruit 2 new
stewards; support all
active stewards
Recruit 2 new
stewards; support all
active stewards
Recruit 2 new
stewards; support all
active stewards
Publicize in local
media
Plan and host signature
community planting
event
Host volunteer
appreciation event
Host 1 community
appreciation event
Host signature
community planting
event
Host volunteer
appreciation event
Host 2 community
appreciation event
Host signature
community planting
event
Host volunteer
appreciation event
Host 3 community
appreciation event
Host signature
community planting
event
Host volunteer
appreciation event
Host 5 community
appreciation event
Develop basic
branded outreach
and promotional
items
Work with schools on
youth stewardship
program
Create updated
branded outreach
and promotional
materials
Publicize first 5 years
of work
Update community
engagement plan
84
Short -Term Strategic Plan Benchmarks 2013 -2017 (continued)
RESOURCES
2017
2018
2019
2020
2021
Convene agency
partners for
preliminary
coordination
Establish
management team
and working partners
Seek additional
partners
Identify and pursue
funding to support
field, community
and administrative
work as needed
Identify and pursue
funding to support
field, community and
administrative work
as needed
Develop business
engagement plan
Seek additional
partners
Identify and pursue
funding to support
field, community and
administrative work as
needed
Expand capacity
for volunteer and
community events
Explore options for
more formalized
management
structure if needed
Identify and pursue
funding to support
field, community and
administrative work
as needed
Expand business
engagement
ADMINISTRATION
Begin planning
for long-range
management
structure
Finalize plans for
management
structure
Establish working
Community
Advisory Committee
and Management
Team
Publish and distribute
20 year management
plan
Write 2017
annual report
Write 2018
annual report
Write 2019
annual report
Write 2020
annual report
Develop 2018
work plan
Develop 2019
work plan
Develop 2020
work plan
Develop 2021
work plan
Develop 2022
work plan
Green Tukwila 20 -Year Stewardship Plan 85
Long -Term Strategic Plan Benchmarks 2022 -2036 (continued)
o
J
W_
"-
2022 -2026
2027 -2031
2032 -2036
Continue work on previously enrolled
acres: 13.5 in 2022; 18.5 in 2023; 24.5
in 2024; 31.5 in 2025; 39.5 in 2026
Continue work on previously
enrolled acres: 47.5 in 2027; 55.5
in 2028; 63.5 in 2029; 71.5 in 2030;
79.5 in 2031
Continue work on previously enrolled
acres: 85.5 in 2032; 87.5 in 2033 -2036
Enroll 5 acres in 2022; 6 acres in 2023;
7 acres in 2024; 8 acres in 2025 & 2026
Enroll 8 acres in 2027; 8 acres in
2028; 8 acres in 2029; 8 acres each
year in 2030; and 6 acres in 2031
Enroll any remaining 2 acres, additional
sites and acquisitions if needed
Conduct 5 -year monitoring and BMP
review
Conduct 10 -year monitoring and
BMP review
Conduct 15 -year monitoring and BMP
review
D
VHost
Recruit and manage 4,000 volunteer
hours annually
Support 20 active stewards
Recruit and manage 4,000
volunteer hours annually
Support 25 active stewards
Recruit and manage 3,000 volunteer
hours annually
Support 25 active stewards
Host annual signature planting event
annual volunteer appreciation
event
Host annual signature planting
event
Host annual signature planting
event
Host annual signature planting event
Host annual signature planting event
Host bimonthly community
appreciation events
Host bimonthly community
appreciation events
Host bimonthly community
appreciation events
RESOURCES
Evaluate needs, costs and resources
based on first 5 years of work
Evaluate and update methods
Evaluate and update methods
Identify and pursue funding to
support field, community and
administrative work needed
Identify and pursue funding to
support field, community and
administrative work needed
Identify and pursue funding to support
field, community and administrative
work needed
Ensure proper funding base is in place
for long -term maintenance, monitoring
and community engagement
Develop annual work plan and write
annual report of accomplishments
Develop annual work plan
and write annual report of
accomplishments
Develop annual work plan and write
annual report of accomplishments
86
APPENDIX I. GLOSSARY OF TERMS
Adaptive Management
A structured, repeating process of decision making
aimed at better understanding a management system
through monitoring, evaluation, and development of new
management strategies. The Green Tukwila Partnership
will utilize an adaptive management strategy to inform its
administrative and restoration practices over time.
Balanced Scorecard
A strategic planning and management tool developed to
measure both financial and nonfinancial performances
against strategic goals. Tukwila's balanced scorecard
measures the performance across three key elements:
fieldwork, community, and resources.
Canopy Cover
The percent of a forest floor or specific geographic
area covered by tree crowns. Assessed using aerial
orthophotographs as well as ground -based techniques,
it can be used for all trees in a given geographic area or
specific tree species. Canopy cover has been shown to be
an important ecological indicator used for distinguishing
plant and animal habitats as well as assessing on -the-
ground conditions in urban areas. The canopy cover
of Tukwila's forested parkland was assessed using aerial
orthophotographs followed by on- the - ground field
verification.
Conifers
Cone - bearing trees, most of which are evergreen, with
needle or scalelike leaves. Examples include pine, fir,
hemlock, and spruce. The dominant conifers found
in Tukwila's urban forest include Douglas -fir, western
redcedar, and western hemlock.
Crown Closure
Canopy closure is the proportion of the sky that is obscured
by leafy vegetation when viewed from a single point on the
ground, looking up. Closure is affected by tree heights and
tree canopy widths and takes into account light infiltration
into the understory. Canopy closure is a data measurement
in the Forest Landscape Assessment Tool (FLAT) used to
categorize Tukwila's forested parkland for the 20 -Year Plan.
Deciduous
A tree or shrub that loses its leaves or needles during the
fall and winter months (in contrast to an evergreen plant).
Examples found in Puget Sound forests include bigleaf
maple, red alder, and snowberry.
Ecosystem
The interactive community or relationships of living
(biotic) organisms such as plants, animals, and microbes
with nonliving (abiotic) components such as air, water,
soils, and weather.
Forest Restoration
Actions and management to reestablish or enhance
processes that support a healthy forest's structure, ecological
functions, and biodiversity levels. Restoration actions may
include removal of nonnative invasive plants, applying
mulch, and planting native trees, shrubs, and ground cover.
In an urban environment, the natural ecological processes
may never be fully restored. Therefore, forests will need
ongoing management with long -term maintenance and
monitoring.
Green Cities Network
The combined regional group of Green City Partnerships,
which currently includes Seattle, Kirkland, Tacoma,
Redmond, Kent, Puyallup, Tukwila, Snoqualmie and
Everett. The Network is not a formally defined entity;
rather, it is made up of the city partners, Forterra staff,
other nonprofits, and participating volunteers who
contribute to achieving the goals of each Green City.
Network participants are invited to share best management
practices, current relevant research, and funding
opportunities.
Green City Partnership
A public - private venture between a local municipality
(e.g., parks departments, public works, utilities, and
other government agencies), community groups, and
Forterra. The vision of each Green City Partnership is to
create a healthy, livable city with sustainable urban forests
and natural areas that connect people to nature through
community-based stewardship.
Greenspace
A protected area of undeveloped landscape such as
grass, trees, or other vegetation set apart for recreational,
aesthetic, or ecological purposes. In the context of the 20-
year plan, greenspace refers specifically to lawns, greenbelts,
meadows, wetlands, and forests within the city of Tukwila.
Invasive plants
Introduced nonnative plant species with traits that allow
Green Tukwila 20 -Year Stewardship Plan 87
them to thrive outside their natural range and outcompete
native plants. Invasive plants are typically adaptable and
aggressive, with high reproductive capacity, and likely to
cause economic and /or environmental harm.
Madrone
Arbutus menziesii (aka Pacific madrone, madrona) is a
broadleaf evergreen tree native to western North America,
particularly to Puget Sound lowland forests. The bark is a
rich orange -red color that when mature naturally peels away
in thin sheets, leaving a smooth greenish appearance. The
Pacific madrone is in decline, especially in urban areas, and is
a difficult species to reestablish. The species offers important
habitat and supports a unique plant community often found
on drier slopes along shorelines, or in areas with sandy or
rocky, well- drained soils.
MU (Management Unit)
A defined geographic area or forest stand within a park
characterized by the vegetation type or conditions present.
Forest stands within Tukwila parks were delineated into
MUs based on one of five categories: forested, natural
(nonforested), open water, hardscaped, or landscaped. MUs
were then further designated based on tree -iage category as
described in the 20 -year plan.
Mulch
A protective covering, usually of organic matter such as
leaves, straw, bark, or wood chips, placed around plants to
prevent weed growth, moisture evaporation, and the freezing
of roots. Covering the ground with mulch is a maintenance
practice used in urban forest restoration following invasive
plant removal and native plant installation.
Natural Area
Undeveloped land, consisting of native and nonnative
vegetation, that is not maintained as an ornamental
landscape, and where normal ecological cycles proceed.
Natural areas can be public or private land. The forest
assessment conducted for the 20 -year plan defines natural
areas as those HMUs with less than 25% tree cover, in
contrast to "Forested Areas," which have more than 25% tree
cover.
Orthophotograph
An aerial photograph that has been adjusted for
topographic relief, lens distortion, and camera tilt. It can
be used to measure true distances, because it is an accurate
representation of the Earth's surface, and is often used with
geographic information systems (GIS).
88
Overstory
The uppermost layer of branches and foliage that forms
the forest canopy. Common overstory trees found in Puget
Sound forests include Douglas -fir, western redcedar, western
hemlock, and bigleaf maple.
Photosynthesis
A process used by plants and some algae to convert light
energy from the sun, carbon dioxide, and water into
carbohydrates that provide sustenance for those organisms.
Photosynthesis takes place in the chloroplast cells of leaves.
The primary by- product of photosynthesis is oxygen.
Riparian
Pertains to the area along the banks of a river, stream, or lake.
Runoff
Runoff refers to unfiltered rainwater that reaches nearby
water bodies by flowing across impervious surfaces such as
roads, parking lots, driveways, roofs, and even compacted
soils in landscapes. When the landscape is undeveloped or
soils are not compacted, rainwater soaks into forest and
meadow soils, where it is filtered by natural processes, slowly
feeding into underground aquifers, streams, and lakes.
The filtration process removes pollutants such as motor
oils, gasoline, fertilizers, and pesticides. Forested parklands
in Tukwila assist in reducing stormwater runoff entering
Possession Sound, the Snohomish River, and Everett's other
streams and wetlands.
Tree Canopy
The uppermost layer of the forest, formed by leaves and
branches of dominant tree crowns. The tree canopy forms the
forest overstory.
Tree Canopy Vigor
Vigor refers to a tree's active, healthy growth. Plants with
"low tree canopy vigor" have stunted growth, premature
leaf drop, late spring -leaf development, sparse foliage,
light green or yellow foliage, twig and branch dieback, or
other abnormal symptoms. A combination of factors (e.g.,
flooding, shifts in environmental conditions, or physical
damage) reduces a tree's vigor. Stress on a tree can make it
vulnerable to diseases and insects that accelerate its decline.
Understory
The vegetation that grows below the forest canopy.
Understory plants consist of saplings of canopy trees,
together with smaller understory trees, shrubs, and herbs.
Examples of understory plants found in Puget Sound forests
include vine maple, beaked hazelnut, tall Oregon grape, salal,
and sword fern.
Woody Shrub
A woody, multistemmed plant that grows to less than 26 feet
tall and is found in the forest understory. Examples found
in Puget Sound forests include red flowering currant and tall
Oregon grape.
Green Tukwila 20 -Year Stewardship Plan 89
GREEN
TUKWILA
PARTNERSHIP