Tree Protection Polling Results – Seattle. WA

Tree protection polling insights

Prepared for the Seattle City Council by the Northwest Progressive Institute team

May 3rd, 2023


Councilmembers, NPI thanks you for your work with Mayor Bruce Harrell to improve climate resilience and strengthen protections for Seattle’s trees. Keeping the Emerald City emerald is an important and laudable objective, but we won’t reach it unless we provide meaningful legal protections to protect more of our existing tree canopy. As you know, a mature tree takes a lifetime to grow. Merely requiring new trees to be planted somewhere else when a mature tree is cut down does not provide a 1:1 replacement. 

We need actionable strategies for tree retention – and for those strategies to be successful, we need to ensure trees are viewed by the law as community amenities rather than obstacles to development. That is why the work you’re currently doing to update Seattle’s tree protection ordinance is so important. 

Trees and more housing go hand in hand. Research keeps demonstrating that access to nature and the outdoors is good for our mental and emotional health. Our built environment can’t just be concrete, asphalt, steel, and glass.  And as our PNW summers become hotter, it’s going to be particularly important that new Seattle residents have access to shade. Urban forests are not a luxury – they are a necessity. 

This memo will walk you through the data that demonstrates that what we’ve just said in the preceding three paragraphs are the strongly held beliefs of an overwhelming majority of Seattleites. Across three different surveys conducted in the past eighteen months, we have repeatedly found massively robust majorities for almost every single tree protection idea that we asked about. 

On many issues that we research, we see a sharp divide among the public. But here, we see widespread agreement that spans the ideological and political spectrum. Washington is the Evergreen State and Seattle is the Emerald City. We are national leaders in environmental protection. We have a strong conservation ethic. Here, we believe the trees are the view. It’s very important that our policies reflect these values. 

Two-thirds of Seattle voters are already concerned about tree and canopy loss

In our most recent survey of the Seattle electorate, conducted in January 2023, in advance of the February 2023 special election, we asked a representative sample of 

QUESTION: How concerned are you about tree and canopy loss in your neighborhood and the city as housing density increases to meet Seattle’s growing population?


40% Very concerned

29% Somewhat concerned

18% Not too concerned

12% Not concerned at all

1% Not sure

Aggregated toplines:

68% Total Concerned

31% Total Not Concerned

Breakdown by council district for this question: 


Breakdown Citywide D-1 D-2 D-3 D-4 D-5 D-6 D-7
Very concerned 40% 51% 38% 37% 44% 33% 42% 26%
Somewhat concerned 29% 28% 24% 32% 23% 30% 32% 28%
Not too concerned 18% 14% 27% 20% 21% 24% 15% 13%
Not concerned at all 12% 7% 11% 10% 12% 8% 11% 32%
Not sure 1% 0% 0% 0% 0% 5% 0% 2%
Total Concerned 68% 79% 63% 69% 67% 63% 74% 54%
Total Not Concerned 31% 21% 37% 30% 33% 32%% 26% 44%
Net Concerned 37% 58% 26% 39% 34% 31% 48% 10%


Of those who said they were concerned, we asked this follow-up question:

FOLLOW-UP QUESTION: You stated you are concerned about losing trees in your neighborhood and the city. How important is having trees and nature in determining where you live in Seattle?


77% Very important

20% Somewhat important

2% Not too important

0% Not important at all

98% Total Important

2% Total Not Important

Seattle voters are not at all opposed to building more housing. But they want to see new apartments, duplexes, triplexes, fourplexes, and the like built without destroying what’s left of our urban forests. 

Trees are important to increasing climate resiliency, Seattle voters say

In a subsequent question in our January 2023 poll of the Seattle special election electorate, we asked respondents to tell us about the role of trees in the city. Nearly all respondents agreed that trees are important to everything from reducing noise to providing visual beauty. What was particularly interesting was that 72% said trees were very important to increasing climate resiliency. The intensity we saw there was only exceeded by providing habitat for birds and wildlife (80% say trees are very important for that.)

QUESTION & ANSWERS: Please indicate how important you think trees are to each of the following:


Important Total Important Total


Very Smwt Not Too At All
Increasing climate resiliency 72% 21% 6% 2% 92% 8%
Reducing air pollution 71% 22% 6% 1% 93% 7%
Reducing stormwater runoff 65% 28% 6% 1% 93% 7%
Habitat for birds and wildlife 80% 16% 3% 1% 95% 5%
Reducing heat island impacts 72% 20% 7% 1% 92% 8%
Noise reduction 54% 34% 10% 2% 88% 12%
Mental and physical health 67% 26% 5% 2% 93% 7%
More pleasant to walk and bike 65% 26% 7% 2% 91% 9%
Visual beauty 69% 27% 3% 1% 96% 4%

Across the lake, voters in Bellevue likewise see tree protection as key to building a livable city, along with more housing

In August of 2022, the Northwest Progressive Institute commissioned – in partnership with the Housing Development Consortium, Sightline, Complete Streets Bellevue, and Eastside For All – a poll of Bellevue city residents that focused on housing. In that survey, Change Research asked 475 Bellevue residents what attributes should be prioritized in the city’s future housing. 

Sufficient tree canopy was the second-highest ranked attribute overall, after cost/affordability. 

QUESTION & ANSWERS:: Which of the following attributes should be prioritized in Bellevue’s future housing? Select the three that are most important to you.


2 3 Not Ranked Total Ranked Avg. Rank
Cost / affordability: Bellevue needs homes that low and middle income families can afford to rent or purchase – and that nonprofit developers can afford to build 32% 9% 9% 50 50 1.6
Sufficient tree canopy: Bellevue needs homes that are built responsibly, with mature trees left standing in order to ensure that neighborhoods remain connected to the natural environment 13% 9 14% 64 36 2.0
Walkability and density: Bellevue needs homes that are within walking distance of common destinations like grocery stores, pharmacies, schools, restaurants, and churches 9% 13 12% 65 35 2.1
Range of sizes: Bellevue needs homes in a range of sizes, including homes that provide more space than a studio apartment but less space than a millennium mansion 10% 14 10% 66 34 2.0
Proximity to transit: Bellevue needs homes that are well served by buses and trains so that residents aren’t forced to buy or lease a car to get around 7% 15 11% 67 33 2.1
Low environmental impact: Bellevue needs homes that are built with high levels of insulation, sustainably-sourced materials, energy efficient appliances, and heat pumps 9% 9 7% 76 24 1.9
Multi-generational dwellings: Bellevue needs homes that can comfortably support more than a single family, or multiple generations of a family 7% 8 10% 76 24 2.1
Local developers: Bellevue needs homes that are built by locally based developers who have a stake in the city’s future and take the time to obtain and utilize community input 4% 7 8% 81 19 2.2
Home office space: Bellevue needs homes that allow residents to work remotely from a dedicated home office, as opposed to a shared space like a living or dining room 4% 5% 6% 85 15 2.1

Tree retention as a strategy for increasing the availability of affordable housing

Additionally, in response to a separate question, the survey found that 64% of Bellevue residents support relaxing restrictions like building height limits for projects that preserve existing mature trees on the property rather than cutting them down. 29% were opposed and 7% were not sure. 

QUESTION & ANSWERS: The Bellevue City Council is considering a number of ideas to increase the availability of affordable housing throughout the city’s mostly residential neighborhoods. Please indicate whether you support or oppose each of the following policies.


Support Oppose Not Total Total Net
Strg Smwt Smwt Strg Sure Support Oppose Support
Relax restrictions like building height limits for projects that preserve existing mature trees on the property rather than cutting them down 32% 31% 11% 18% 7% 64% 29% 35%

Voters across the state feel similarly

In NPI’s most recent statewide survey, conducted in March of 2023, our other frequent pollster Public Policy Polling asked the following question of 874 likely 2024 Washington general election voters:

QUESTION: The Legislature is considering several bills to address Washington’s housing crisis, including legislation that would make it easier for developers to build missing middle housing like duplexes or low-rise apartments. Do you strongly support, somewhat support, somewhat oppose, or strongly oppose including tree protection requirements in these housing bills to maximize the retention of existing mature trees on parcels being redeveloped and ensure that new trees get planted in low canopy areas to improve climate resiliency and environmental equity?


49% Strongly support

17% Somewhat support

9% Somewhat oppose

14% Strongly oppose

10% Not sure

Aggregated toplines:

66% Total support

23% Total oppose

That’s close to 3-to-1 support vs. opposition. 

In the King County subsample, the numbers were:

55% Strongly support

18% Somewhat support

7% Somewhat oppose

10% Strongly oppose

10% Not sure

Aggregated toplines for King County: :

73% Total support

17% Total opposition 

The need for updated tree protections in Seattle

In our July 2021 poll of the Seattle electorate, Change Research asked 617 respondents (likely Top Two voters) if they wanted to see Seattle’s tree protection ordinance strengthened, specifically to bolster tree equity. 82% said they strongly or somewhat agreed that the ordinance should be strengthened. 

QUESTION: Do you agree or disagree with the following statement: Seattle’s tree protection ordinance should be strengthened to include increasing tree planting in low income and previously redlined neighborhoods with insufficient tree canopy to reduce heat island impacts and counter climate damage?


 57% Strongly agree that Seattle’s tree protection ordinance should be strengthened

25% Somewhat agree that Seattle’s tree protection ordinance should be strengthened

4% Somewhat disagree that Seattle’s tree protection ordinance should be strengthened

7% Strongly disagree that Seattle’s tree protection ordinance should be strengthened

7% Not sure

Aggregated toplines:

82% Total agree

11% Total disagree

Ideas for protecting trees

In that same survey, we asked about this set of ideas for protecting trees:

QUESTION & ANSWERS: Please indicate your support or opposition for each of the following potential ideas for updating Seattle’s tree protection ordinance.


Support Oppose Not Total Total Net
Strongly Somewhat  Somewhat Strongly Sure Support Oppose Support
Increasing protections for significant and exceptional (large) trees 52% 25% 6% 7% 9% 78% 13% 65%
Adding replacement requirements for significant and exceptional tree removal 47% 29% 6% 7% 11% 76% 13% 63%
Creating a city tree planting and preservation fund 47% 30% 7% 8% 8% 77% 14% 63%
Requiring tree care providers (arborists) to meet minimum certification and training and register with the city 41% 34% 7% 6% 11% 75% 14% 61%
Creating a permitting process for removal of significant trees (trees greater than six inches in diameter at four and a half feet high) 31% 26% 14% 14% 15% 57% 28% 30%

Seattle has already enacted legislation requiring tree care providers to meet minimum certification and training and register with the city. Kudos on that!

In our July 2021 survey, we next asked: 

QUESTION: Cities like Austin, Texas require developers to maximize the retention of existing trees throughout the planning, development, and construction process, while Seattle allows building lots to be cleared of trees during development. Do you support or oppose requiring Seattle developers to maximize the retention of existing trees throughout the planning, development, and construction process?


58% Strongly support requiring Seattle developers to maximize the retention of existing trees

23% Somewhat support requiring Seattle developers to maximize the retention of existing trees

7% Somewhat oppose requiring Seattle developers to maximize the retention of existing trees

6% Strongly oppose requiring Seattle developers to maximize the retention of existing trees

6% Not sure

Aggregated toplines: 

81% Total Support

14% Total Oppose

We can see from the answers to this question that a very large majority of Seattle voters favor requiring Seattle developers to maximize the retention of existing trees as part of their projects. Again, this just shows that Seattleites view trees as community amenities rather than obstacles to development. 

More ideas for protecting trees

In our autumn 2021 general election survey – which anticipated the victories of Mayor Bruce Harrell, City Attorney Ann Davison, and Councilmembers Teresa Mosqueda and Sara Nelson – we asked likely general election voters about another set of tree protection ideas. As before, we found plenty of support.

The following questions were asked of 617 respondents in October of 2021 by Change Research: 

QUESTION: Portland, Oregon requires developers to provide a comprehensive Tree Survey and Tree Plan at the beginning of the building development process. Developers enter the Tree Survey information into a spreadsheet, which facilitates data collection on tree loss and replacement. Supporters say Seattle could follow suit to ensure the city maintains a healthy tree canopy, while opponents say it would be yet another regulation that would slow down development. Do you support or oppose requiring developers in the City of Seattle to complete a Tree Survey and Tree Plan prior to construction permits being approved?


50% Strongly support

24% Somewhat support

9% Somewhat oppose

9% Strongly oppose

8% Not sure

Aggregated toplines

74%Total Support

18% Total Oppose

We then asked: 

QUESTION: Oversight of trees in Seattle is currently overseen by nine city departments. Do you support or oppose creating a new Seattle Department of Environment and Climate that would include a consolidated urban forestry division?


44% Strongly support

28% Somewhat support

6% Somewhat oppose

12% Strongly oppose

10% Not sure

Aggregated toplines:

72% Total Support

18% Total Oppose

Finally, we asked:

QUESTION & ANSWERS: Please indicate your support or opposition for each of the following ideas for updating Seattle’s tree protection ordinance.


Support Oppose Not Total Total Net
Strongly Somewhat  Somewhat Strongly Sure Support Oppose Support
Give priority to planting native and climate resilient trees 66% 23% 3% 3% 5% 89% 6% 83%
Charge developers replacement fees for trees that they remove and don’t replant, with the amount of the fee corresponding to the size of the removed tree to make up for lost canopy 56% 22% 7% 8% 8% 77% 15% 62%
Increase building setbacks to allow larger, street-facing trees to be planted 38% 29% 10% 10% 14% 67% 20% 47%
Reduce the number of significant, non-exceptional trees that can be removed by private property owners from three (3) per year to two (2) in three years 29% 26% 14% 14% 17% 55% 28% 27%
Lower the upper limit for exceptional tree protection from thirty (30) inches in tree diameter to twenty-four (24) inches in diameter 29% 21% 12% 13% 25% 50% 25% 25%


Across all of our public opinion research on tree protection, we have never found less than a majority supportive of any of the ideas and strategies we have asked about for retaining trees and facilitating the planting of new trees. There’s broad, deep, and enthusiastic support for making the Emerald City a national leader in both tree protection and smart density. For this aspiration to be realized, we need an updated tree protection ordinance with teeth in it. The trees cannot speak for themselves, to paraphrase from The Lorax, so it’s critically important that the law speak for the trees. Please use this lens when considering and voting on the amendments that have been submitted to the draft ordinance. 

Thank you for your service to the people of the City of Seattle. 


Please get in touch with us.

Updated Comments on Tree Ordinance Amendments proposed to be voted on by the Land Use Committee on May 4th

e-mail sent to Seattle City Council
Dear Councilmember Dan Strauss,
Concerns regarding amendments are based on Wednesday, April 26 amendment sheet, which is the latest the public has seen.
We have not seen any updates on amendments on the Land Use Committee Agenda sent out today, May 1 for the two scheduled meetings on May 4th, so these comments are based on last week’s update.  Only 2 of the 9 sections had revisions last Wednesday and actual amendment language was still not available in most cases.
A2 – Why allow for 100% lot coverage in MR, commercial and SM zones? Do we want zero tree zones and more heat islands? This was not discussed in the 2023 DNS or 2023 Addendum. The 2021 canopy study says the multifamily zones haves a 23% canopy cover, the commercial/mixed use has a 12% canopy cover. Why put in things that guarantee tree removal. Other cities are struggling to add trees.
A4 – A guaranteed 85% lot coverage needs to be removed. The 2023 Addendum to the 2022 DNS did not take into account the impacts of HB 1110 and other state legislation that makes the ability to retain trees much more difficult. The Hearing Examiner last stated that the balance of keeping trees and increasing housing were both goals in the Comprehensive Plan and that last year’s draft balanced these goals. Now new provisions are being added that will remove more trees. Existing trees are the survivors.  Replacing them is costly and removing their current benefits in an increasing climate crisis.
A4, A-5, and A6 – A guaranteed 85% lot development area needs to be removed. Keep the flexibility using FAR as the current ordinance language provides to let tree retention, protection and planting be decided lot by lot depending on what trees are on the lot and moving building placement if possible.. Exceptions can be made for greater building lot coverage if conditions permit but there is no flexibility for trees with an 85% guarantee for development area.   Existing townhouses less than 15 feet wide have been built in Seattle. Retain flexibility in design and lot placement on site development
A-7 Support creation of Tree Preservation and Planting Areas of 20% for multifamily areas and 40% for Neighborhood Residential areas like Portland, Oregon has done. With state legislation requiring allowing 4 plexes and 6 plexes across most of Seattle having passed the State Legislature with HB 1110,  Seattle will never reach 30% tree canopy but will shift to 23% or less currently in the MR zone. We need trees where people live, in their neighborhoods, for a livable city.
B-7 Allow the in-lieu fee fund to be the One Seattle Tree Fund proposed by Mayor Harrell. Allow it to both preserve and plant trees like Portland, Oregon does. Add to tree replacement, that funds can also be used to protect existing trees, including tree groves,  by use of covenants and land purchases and donated land to create neighborhood dedicated tree parks and protected tree areas.
B-10 Expand the possible options to be explored to include creating a Climate and Environment Dept that has an Urban Forestry Division. The goal shall be to give Green Infrastructure protection and enhancement as an important focus on livability in the future of our city. We are facing an impending climate crisis and need to think of new ways to address the future by thinking boldly.
C-2 – Rather than “request SDCI modify its practices to consider trees at the beginning of the tree permit process” require that they do by requiring a tree inventory and a tree (landscaping plan) plan be submitted with a request for a development permit. Other cities like Portland, Oregon do this. Mayor Harrell has said we need data to make good decisions, and this is one way to get data. Require that developers maximize the retention of all 6″ DSH trees and larger (not just 12″ DSH and larger) throughout the entire development process. Six inch DSH trees are established trees, survivors, that have a head start on growing larger and do not need $4000 or more spent to plant and maintain for 5 years.
D-7 As written, there are 2 problems here.  This provision could apply to vacant lots which were to have no trees removed unless hazardous, and if a developed lot, why allow removal of more trees just because a lot has 40% trees.  This was not discussed in the DNS or addendum and states no compelling reason to allow this loophole to remove more trees.
E-4 would require a lot of replacement trees. Certainly 1:1 (which may become equivalency in the distant future) is not an answer. The UFC recommended 2 for 1 for trees 12-24″DSH , 3 for 1 for 24-36″ DSH and 4 for1 for trees over 36″ DSH Mercer Island has 1 for < 10 ” DSH, 2 for 1 for 10″ -24″ DSH ,3 for 1 for 24″-36″ DSH , and 6 for 1 for over 36″ DSH and exceptional trees.
E-5 and E-10 address the same issue and should be combined.
F-3 – Should include two violations in a year for any illegal tree cutting rules, eg two violations of removing a Tier 1, Tier 2, Tier 3 trees or more than two Tier 4 trees in 3 years.  Minor violations, like paperwork or address violations should have fines but not push a company out of the city. Let fines increase with multiple minor violations if necessary for corrective action by a company.
F-4 – Several reasons to keep 15% or greater canopy area and branches 2 ” diameter as reportable work – It is consistent with SDOT procedures, allows collection of data of canopy removal (both canopy area and canopy volume loss), and allows SDCI and public ability to check on tree trimming work. Likely outcome of change will be much less tree trimming work will be reported as reportable work.
G-6 – Change “require consideration” to “require” Tree Protection Areas must be set up for all Tier 1 – Tier 4 trees on neighboring property whose root zones are also on the lot where the development is occurring. This includes both public and private trees.
H-4 – Opening up options to remove Heritage Trees besides being hazardous reduces them to Tier 2 trees -Exceptional Trees.
Keep Heritage Trees non-removable unless they are a hazard tree. There are not that many of them and most are said to be street trees.
I-4 As proposed by Urban Forestry Commission, amend the Tier System to include the currently used nomenclature to make it easier for the public to understand. eg Tier 1 – Heritage Trees,, Tier 2- Exceptional Trees, Tier 3 – Significant Trees 12-24″ DSH and Tier 4 Trees – Significant Trees 6-12″ DSH. We are aware of no other city that has a Tier System which creates confusion and de-emphasizes the value of the trees to the public.
Steve Zemke
Friends of Seattle’s Urban Forest

Documents Relating to Seattle Draft Tree Protection Ordinance April 26, 2023

The Seattle City Council is in the processing of updating Seattle’s Tree Protection Ordinance. Wording for specific amendments is happening now. Final discussion and adoption of amendments will take place at two Special Land Use Committee meeting on Thursday May 4th, 2013 at 9:30 AM and 2 PM meetings

CB 120534 AN ORDINANCE relating to tree protection; balancing the need for housing production and increasing tree protections; and amending Sections 23.44.020, 23.47A.016, 23.48.055, 23.76.004, 23.76.006, and Chapter 25.11 of the Seattle Municipal Code.

Briefing, Discussion, and Possible Amendments

Full Text: CB 120534
Summary and Fiscal Note
Summary Att 1 – Expanded Summary of Code Changes
Director’s Report
Draft Directors Rule 2023-XX – Tier 2 Trees
Draft Directors Rule 2023-XX – PIL
2023 Tree Hearing Schedule
Tree Protection Presentation (3/22/23)
Tree Protection Presentation (3/29/23)
Central Staff Memo
Central Staff Presentation (4/7/23)
Tree Protection Presentation (4/7/23)
2023 Tree Hearing Schedule (updated)
Central Staff Memo (4/21/23)
2023 Tree Hearing Schedule (updated v2)
Full Text: CB 120534 v2
Full Text: Word v.2 for editing
Table of Amendments v2 (added 4/26/23)

Here is a list of Seattle City Council members and their Land Use staff.

2023 Seattle Tree Protection Poll Briefing by NPI

January 2023 Seattle Tree Protection Findings Briefing Packet

Click on bottom of slide above to see results NW Progressive Institute – January 2023

See also::

Second set of Seattle tree protection poll findings affirms voters value urban forests –  NW Progressive Institute – Dec 20, 2021

Seattle voters overwhelmingly favor policies to protect and expand the city’s tree canopy  – NW Progressive Institute – Sept 15, 2021

2023 Tree Protection Ordinance Update Documents


Council Bill 120584 AN ORDINANCE relating to tree protection; balancing the need for housing production and 6 increasing tree protections; and amending Sections 23.44.020, 23.47A.016, 23.48.055, 7 23.76.004, 23.76.006, and Chapter 25.11 of the Seattle Municipal Code.

– Summary and Fiscal Note
– Summary Attachment – Expanded Summary of Code Changes
– Draft Director’s Rule 2023-XX – Tier 2 Trees
– Draft Director’s Rule 2023-XX –  PIL
Director’s Report


Priority Talking Points on Amending Mayor Harrell’s 2023 draft Tree Ordinance

Friends of Seattle’s Urban Forest

Talking Points for Seattle Tree Protection Ordinance Update testimony before the Land Use Committee

  • Remove the guaranteed  “development area of 85%.” for lowrise, midrise, commercial and mixed zones. If middle housing legislation passes in Olympia, all of Seattle will be up zoned  by the state as multifamily. It will seriously reduce space for trees on building lots in the city. Seattle City planners need flexibility to save trees for healthy communities.
  • Require 20% lot allowance for “tree preservation and planting areas” in multifamily areas and 40% tree lot allowance for 1-4 units in the neighborhood residential zone.  Portland passed legislation in 2020 to allow up to 4plexes  in their neighborhoods after the state mandated zoning updates. Portland responded in Nov 2022 to update the tree protection legislation.
  • Require a Tree Inventory of all 6″ DSH and larger trees and a Landscape Plan prior to any Building Permit being issued.
  • Require “maximizing the retention of existing trees 6″ DSH and larger” throughout the entire development process. Urban forests need a diversity of tree ages and species to be healthy and sustainable.
  • Require all in-lieu fees for trees that can’t be preserved or replaced on site to be based on the square inches of trunk starting at 12″ DSH to equalize their value based on size. Larger fees can both serve as a disincentive to remove trees and also more fairly compensate for the increasing ecoservices value lost by the city as trees get larger. In-lieu fee should be $17,87 per square inch for all removals 12″ DSH and larger.
  • Require for replacement 2 trees for 12-24″ DSH trees removed, 3 trees for 24 – 36″ DSH and 4 trees for above 36″ DSH for more equivalency of the increasing value of ecoservices trees provide as they increase in size. One for one replacement is no equivalency for what is lost as trees increase in size. Mayor Harrell’s Executive order 2023-03 requires the city to replace any healthy tree removed at a 3:1 ratio.
  • Keep the long standing and widely used exceptional tree and significant tree nomenclature.  Remove the term “tiers” and give trees their dignified names back, like exceptional and significant, so the community can continue its relationship with trees, rather than thinking of them only as numbers.

2023 Seattle Mayor Harrell’s Draft SDCI Tree Protection Ordinance Issues

2023 Seattle Mayor Bruce Harrell’s Draft Tree Protection Ordinance – Issues 

We support the following provisions in the 2023 SDCI draft Tree Protection
1. Lowering the upper limit for exceptional trees to 24” Diameter at Shoulder Height (DSH) from 30” DSH
2. Requiring street trees be planted whenever development would add one or more principal dwelling units on a lot
3. Continuing protection for exceptional trees less than 24” DBH and tree groves and heritage trees
4. Continuing prohibition on removal of trees 6” DBH and larger on undeveloped lots.
5. Requiring replacement of all 12” DSH and larger trees removed by developers
6. Requiring an in-lieu fee for developers to replace trees 12” DSH and larger that cannot be replaced on the development site.
7. Requiring in lieu fees be used to replace and maintain newly planted trees removed by developers
8. Limiting removal of 6”-12″ DSH significant outside development to two trees in 3 years.
9. Protected trees and replaced trees are covered by a covenant.
10. Requiring 5-year maintenance for relocated or required replacement trees
11. Requiring 6-day advance notice online of all 6” DSH and larger trees proposed for removal by Tree Service Providers, posting on site on day of work and remaining for 5 days after removal.
12. Creation of 3 new SDCI positions to monitor and assist in implementing and enforcing provisions in the ordinance draft.

Key provisions that need to be revised or added to the draft tree protection ordinance:  

 1.Require 20% lot allowance for “tree preservation and tree planting areas” in multifamily areas and 40% lot allowance for 1-4 units in the neighborhood residential zone as Portland Oregon does in their family residential zone.  Portland passed legislation in 2020 to allow up to 4plexes  in their neighborhoods after the state mandated zoning updates. Portland responded in Nov 2022 to update the tree protection legislation.

  2. Remove the guaranteed “85% lot development area” provision.  If the current middle housing legislation passes in Olympia, almost all of Seattle would be affected by this change, with a significant loss of tree canopy city wide. The city needs flexibility to evaluate development and protecting trees lot by lot, not one size fits all circumstances. 

 3.  Require a Tree Inventory of all trees 6” DSH and larger and a Tree Landscaping Plan be submitted by developers, as Portland Oregon does, prior to any building permits being approved. This information fits with collecting in lieu fees prior to issuing building permits and facilitates reporting and tracking of tree loss and replacement, rather than city workers having to pull this information from site plans. Mayor Harrell’s Executive Order asked for data on trees removed and replaced. Getting this information up front from developers is the best way to do this. 

 4. Require developers throughout the total development process to maximize the retention of existing trees 6” DSH and larger with adequate space for trees to grow and survive. The current draft removes consideration of protecting 6”-12” DSH trees and also removes them from site plans. Keep them on the site plans and protect them during development.  Trees 6” DSH and larger represent 45% of trees in the NR zone according to Seattle’s Ecosystem Values Report. Most of these trees are established potential replacement trees for existing large trees that die. Trees 12” DSH and larger only represent 18% of the trees in the NR zone. A diversity of ages and species for trees is essential for a healthy urban forest. 

 5. Retain definitions and use of exceptional and significant trees. Remove the confusing and biased proposed new classification of trees as Tier 1, Tier 2, Tier 3, and Tier 4. The use and understanding of trees as exceptional has been in the tree ordinance since 2001 and described in more detail in the 2008 Director’s Rule. 16-2008. Significant trees are understood to be those 6” DSH and larger that are not exceptional. Many other cities, including in this region, use these definitions.  

 6. Require for replacement 2 trees for 12-24″ DSH trees removed, 3 trees for 24 – 36″ DSH and 4 trees for above 36″ DSH for more equivalency of the increasing value of services trees provide as they increase in size. One for one replacement is no equivalency for what is lost as trees increase in size.  Require that tree replacement numbers increase with the size and canopy volume of the removed tree. such that in 25 years or less they will reach equivalent canopy volume lost – either on site or pay a replacement fee that also increases with the size of the tree removed. Just requiring replacement with a tree or trees that “results upon maturity, in a canopy cover, that is roughly proportional to the canopy cover prior to removal” ignores the services the tree provides and would have continued to provide if not removed.  The fact that removing an 80-year-old tree takes 80 years to reach any equivalency to what was lost, needs to be considered in responding to the climate crisis and climate resiliency needs. No language is added to specifically consider the size of trees removed and the ecosystem services lost when a tree is removed.  One reason to increase the required number of trees to be replanted or pay a higher in lieu fee when trees are replanted is to compensate for the magnitude of the tree loss and the multiple decades and cost it takes to replace them 

 7. Increase in lieu fee schedule to require the $17.87/square inch in-lieu fees to start with 12″ DSH trees rather than 24″ DSH trees. In-Lieu fees need to adequately cover the city’s additional cost of planting and maintaining the trees for 5 years. 

 8. All replacement in lieu fees and fines should go into a One Seattle Tree Fund as stated in Mayor Harrell’s ‘s Executive Order. It should be a dedicated Tree Planting and Preservation Fund like Portland, Oregon has (not into SDCI’s budget). The Fund should be added to this draft. The Fund should report yearly on its budget to the City Council and Mayor. The One Seattle Tree Fund should be overseen by the City Urban Forester located in OSE because the distribution of funds would be interdepartmental. Allow the One Seattle Tree Fund (Tree Planting and Preservation Fund) to also accept fines, donations, grants, purchase land, set up covenants and for educational purposes as Portland, Oregon does. 

 9. The role of the new City Forester position created by the Seattle City Council in OSE should be defined in this ordinance. 

 10. Create an Urban Forestry Division within SDCI with additional staff as recommended in a separate budget provision or expand the Urban Forestry staff and responsibility in the Office of sustainability and Environment for independent oversight of trees. 

 11. Expand the existing Seattle Department of Transportation (SDOT) Tree Removal and Replacement Permit Program using the Accela database system to include SDCI to cover all significant trees 6” DSH and larger, and all exceptional trees, on private property in all land use zones, removed both during development and outside development. The proposed ordinance remains a complaint-based system relying on citizens which has been proven to not be effective in code compliance. SDCI only has 2 arborists who are mostly check site plans and in the field. 

 12. Require SDCI to submit quarterly reports to the Office of Sustainability and Environment on tree removal and replacement as currently required by other City Departments and as required yearly by Mayor Harrell’s Executive Order 

 13. Extend ordinance to cover all land use zones, including Highrise, Industrial, Downtown and Institutions 

 14. Allow city certified inspectors to enter property if necessary to ascertain any illegal tree activity 

 15. Expand the required tree protection covenant to include a replacement requirement for a tree that dies. Make it a permanent “protected tree planting site” for the life of the building. 

17. Remove or clarify language of tree drip line “may be irregular in shape to reflect variation in branch outer limits” Dripline is used to determine tree protection area and branches shortened in some areas may not reflect root structure or may have been removed in certain areas if tree has been limbed up. 

 18. Require that maintenance of relocated and replacement trees include “watering as needed” 

 19. Require street trees be planted if ADU’s are added to a lot. ADU’s, particularly Detached ADU’s, reduce space for trees on site and increase tree removal and are currently exempt from original lot coverage limits in NR zone. 

 20. Remove the 1000 square feet addition to an existing structure exemption requiring planting street trees. Additions increasing the building footprint are removing existing or potential tree planting and preservation space. 

 21. Give the SDCI Director the authority to reduce or waive any fees assessed by this ordinance, taking into account a homeowner’s financial circumstances or ability to pay. 

 22. Split the purpose and intent section. Add to intent “address climate resiliency and reduce heat island impacts across the city” 

23. Require removal of invasive plants, like ivy, scotch broom, and holly from development sites to help stop the spread of invasive species in our city that add to maintenance costs and replacement of dying trees.  24.  

4/3/2023 draft – Please contact Steve Zemke with any additional issues, concerns and/or corrections, regarding the above document. Thanks 

Preliminary evaluation of the draft 2023 Seattle SDCI tree ordinance update

The following is a preliminary evaluation of the draft 2023 Seattle SDCI Tree Protection Ordinance update. 3/17/2023
  • 2023 Draft tree protection ordinance update being presented to the city is now a tree and housing ordinance. “An Ordinance relating to tree protection: balancing the need for housing production and increasing tree protections and amending Sections 23.44.020. 23.47A.016, 23.48.055,23.76.004. 23.76.006 and Chapter 25.11 of the Seattle Municipal Code.
  • The 2023 draft tree ordinance has been significantly changed from the 2022 draft. Many of the changes follow those recommended by the Washington building industry.  Neither the Seattle Urban Forestry Commission or the public was presented with the proposed ordinance changes to discuss them prior to their release, the same as with the 2022 draft.  Not all of the documents have been presented or are readily accessible to the public including any new Director’s Rules, or An Expanded Summary of Code Changes or SDCI Director’s Report – Tree Legislation March 6, 2023. Also not available is a detailed comparison of the changes made from the 2022 draft on which a determination of non-significance was made.
  • Removed definition of exceptional trees in current ordinance. They would now just be called Tier 2 trees
  • Removed definition of significant trees that was in 2022 draft last year.
  • A proposed renaming of trees would create confusion and bias by deleting the common definition of trees as either exceptional or significant. It would classify trees as Tier 1, Tier 2, Tier 3 and Tier 4. The Tier number goes up as the size of the tree decreases. Many other cities use the exceptional and significant terminology as has Seattle for many years. A Tier classification is not terminology used by other cities and should be rejected.. The re-classification is an attempt to diminish the public perception of the value of trees by removing common nomenclature the public understands and will hurt efforts to protect and plant trees.
  • Removes protections for significant  that are 6 – 12 inches DSH. These trees would be  called Tier 4 trees. They would no longer be required to be on development site plans and could be removed during development without the city considering them for protection. Previous language talked about protecting potential exceptional trees. Many are potential replacement trees for our urban forest as older trees die. This is also a loss of critical data needed to track tree loss and replacement as required by Mayor Harrell’s Executive order.
  • The proposed ordinance does not cover trees in the industrial or downtown areas and is only updated for institutions when they develop a new Master Plan.
  • Buildings would be allowed to cover 85% of the lot in multi-family zones, eliminating space for trees. Seattle’s Neighborhood Residential (formerly single-family) zone is poised to become a multi-family zone if the state middle housing bill passes.
  • A new street tree requirement would only apply to homes where single-family houses are built, not new multifamily family housing in neighborhood residential zone.. The Building Industry lobby in the Washington State Legislature is pushing for townhouses and other multifamily housing in Seattle’s neighborhood residential zone. All housing built, regardless of the housing zone, should be required to plant street trees.
  • Added definition of a Tier 1 tree as a heritage Tree. There are only about 178 in Seattle according to SDOT map. A separate number of 131 has been mentioned. They should continue to be under the definition of exceptional trees.
  • When no new development is proposed on developed property, two Tier 3 trees (12″ DSH to 24″DSH non-exceptional) in 3 years may be removed in Neighborhood Residential, Lowrise, Midrise, Commercial and Seattle Mixed Zones.  Says no more than three Tier 3 and 4 trees may be removed in any one year period in all other zones. Doesn’t say what those zones are but High Rise and Industrial are not listed in previous sentence. 
  • Does not require tree inventory and landscape plans be done prior to issuing building permits like Portland, Oregon requires. This means no data is being collected on tree loss or replacement on site. Site plans are not in an accessible data form, requiring city workers to retrieve and put in a database system increasing costs for the city. Developers should submit the data in the form of a tree inventory as Portland Oregon requires. . And the draft does not require 6 -12 inch DSH trees to be on site plans. This is inconsistent with other City Departments like SDOT which requires permits to remove 6″ DSH trees and larger. Mayor Harrell’s Executive requires this collection of data. It needs to include tree species, DSH, tree health, and the reason for removal to help assess changes in the city’s tree canopy.
  • Only recording 12″ DSH and larger trees is only about 18% of Seattle’s trees in neighborhood residential zone.  6″ DSH trees represent about 45% of trees in neighborhood residential zone according to Seattle Forest Ecosystem Report
    • Still only requires developers plant one or more trees for trees removed. Replacement  at maturity must roughly equal canopy area lost. The number of trees required for replacement for an 80-year-old tree when only one for one replacement is required is not any equivalency in terms of canopy volume and environmental benefits lost. Replacement of one tree to reach equivalency takes 80 years, assuming it survives.  As far as we know no more than “one for one” tree replacement has ever been required. No data records are kept on tree replacement. Replacement language was first in the 2001 Ordinance but only within the last several years has SDCI put language to that effect in their client assistance memos.  No fund or records exists of any funds collected by the city to replant trees off site in public areas. Also no records of trees planted off site exist that I am aware of. There is no database record of trees replaced on site. No replacement required for non-development removal of trees.
  • Draft ordinance does not set up a separate Tree Planting and Preservation Fund but only has SDCI collecting the funds. Portland Oregon has a Tree Planting and Preservation Fund administered by the City Forester, maintained as a separate fund and  independent of their general fund or building department. Mayor Harrell’s Executive order 2023-03 One Seattle Tree Plan – Growing and Fostering an Equitable Tree Canopy on Public Land orders the creation of a One Seattle Tree Fund but it is not in the draft. It should be located in the Office of Sustainability and Environment under the oversight of the City Urban Forester to insure oversight and independence. Portland Oregon’s Fund is overseen by their urban forester, independent of their building department 
  • Language reverts to only requiring 3 days posting online for Tree Service Provider work. The City Council just passed an ordinance to require 6 business days’ posting online. The six business days need to be maintained. The online reporting also needs to require tree species and reason for tree removal for all work done, not just “deciduous trees” as reported in some instances.
  • New – in lieu fees collected for replacing trees 12″ DSH and larger during development. No reference to trees removed outside development for tree replacement. Portland requires at least one tree be replanted for trees removed outside development.  In-lieu fee amount to be decided by SDCI Director’s Rule. In lieu fees appear to have changed significantly from the draft Director’s Rule X-2022. Significant, non-exceptional trees 12″ DSH and larger in lieu fee have increased to $2833. Exceptional Trees are based on $17.87 per square inch. Portland, Oregon charges $450/diameter inch. A 24″ diameter tree in Seattle would have an in-lieu of $8,080, in Portland it would be $10,800.
  • No requirement for property owners to get a permit to remove a tree, unlike SDOT and many other cities require. The Ordinance update remains a complaint-based system by citizens which has been proven to not be very effective. SDCI has only 2 arborists who it appears do not have time to do field checking. SDCI relies on project planners to do any checking in the field it appears but there is no requirement they be arborists or city foresters.
  • The City urban forester position approved in the city budget and responsibilities is not included in the ordinance and needs to be added. The City Urban Forester should oversee the One Seattle tree Fund  proposed by Mayor Harrell. Also the fund is proposed to look for outside funding as Portland does for their fund.
  • Draft Director’s Rule X-2023 Designation of Tier2 Trees (Previously Exceptional Trees) does not mention tree groves.
Please send any corrections or additional evaluation to to help complete this document. Thanks.

Comments on Seattle’s 2021 Tree Canopy Assessment Final Report

Comments on Seattle’s 2021 Tree Canopy

Assessment Final Report

  1. The City of Seattle 2021 Tree Canopy Assessment Final Report was produced by the City of Seattle’s Office of Sustainability and Environment using findings from the University of Vermont Spatial Analysis Lab report. However, the interpretation of data was done by unnamed people in the city of Seattle, who wrote or reviewed the “final report”.  The University of Vermont collected some of the data but are not the authors of the report. 
  2. The report defines tree canopy as “The layer of leaves, branches and stems that provide tree coverage of the ground when viewed from above.” Not mentioned is that the measurement is done at 8 feet above the ground. This is in contrast to US Army Corps of Engineers, who defines the Tree strata as starting at 20 feet in height, and the shrub/sapling layer from 3-20 feet in height 
  3. So, the City of Seattle canopy actually includes all shrubs and hedges such as laurel, holly and rhododendron bushes that frequently are over 8 feet high, and smaller saplings. The canopy measured would  more accurately be described as “tree and shrub cover.”
  4.  Although asked and confirmed before the report was released that the report would look at tree canopy volume, the report has no such analysis despite LIDARS ability to do so. This is important as tree canopy volume is a more accurate measure of the environmental services trees can provide to cities, as compared to tree canopy area.
  5. While the report defines a large (exceptional) tree as > 30 inches diameter, it does no analysis of large trees gains or losses, and neglects to compare any changes in large exceptional trees over the time period. 
  6. The report mentions trees planted by the city but provides no data on any survival rates of the trees planted. Also, the number of trees removed by SDOT or Parks is not given,  only the number of new plantings. 
  7. The report looked at tree loss during development but only looked at development projects that were begun and completed between 2017 and 2021. The actual tree loss calculation should have looked at all projects that begun between 2017 and 2021 for the most accurate results, not just those that were completed.  What is missing are projects that begun in that time period but were not completed. This is important as trees are usually removed at the beginning of projects, so the actual tree loss is likely significantly higher than what was reported. Also, if the next 5-year analysis follows the current calculations, projects begun before 2022 but completed after 2022 will not be in the analysis, leaving a gap in calculating tree loss during development. 
  8. Key data points in Table 4 in the Appendix show that redeveloped parcels in neighborhood residential zone saw a 33.6% loss of tree canopy and redeveloped parcels in multifamily zones saw a 49.6% reduction in tree canopy.  Issues of concern for future canopy loss include middle housing legislation being considered by the Washington State legislature which would basically convert most of Seattle’s neighborhood residential zone to the multifamily zone. Also, ADU legislation was passed in Seattle in July 2019 for the neighborhood residential zone which will allow 3 units of housing to be built on any lot, increasing potential for additional tree loss. 
  9. Figure 8 is in contrast to other references on trees and urban Island heat impacts. Figure 8 is a scatter plot showing the relationship between maximum afternoon temperature and percent tree canopy, and the report somehow concludes that “…at the hexagon scale on a hot day (where a hexagon is the size of several city blocks) hexagons with 26% tree canopy experienced temperatures that were 1-degree lower than hexagons with no canopy.” This interpretation is misleading as to the on the ground results and is an example on how statistical analysis can be misused. See references below for additional information: 
  •  The original report “Seattle and King County Washington Heat Watch Report” done in 2020 reported as high as a 24-degree F temp difference across the county. The analysis of heat impacts is much more nuanced and is affected by a number of things like time of day, tree canopy, buildings and pavement, closeness to water and size of area considered. The “one-degree lower statement” unfortunately is contrary to what many other researchers have found and clearly misrepresents the temperature differences between areas with trees and those not having trees. 
  • NPR – “In Seattle the difference between the coolest and hottest neighborhoods could be as much as 14.5 degrees, according to a 2019 NPR analysis of surface thermal data from NASA and US Geological Survey satellite imagery from summer days in the last decade.” 
  • King 5 June 23, 2021  “Areas of King County with more paved landscapes and less tree canopy are feeling the heat more intensely than less urbanized areas, according to a new study from King County and Seattle. More urbanized areas were as much as 20 degrees hotter due to an abundance of hard surfaces like parking lots, rooftops and streets which absorb heat, 
  • According to Portland State University research – “While testing solutions that reduce urban heat, the study … showed that paving over places that previously had a lot of tree canopy could raise the temperature as much as 25 degrees Fahrenheit on a summer day. Nearby neighborhoods would experience a spillover effect.” Portland State University Study Demonstrates How Plants, Trees, and Reflective Materials Can Reduce Extreme Heat of City Neighborhoods, 2019
  • New York Times – Hidden Toll of the Northwest Heat Wave: Hundreds of Extra Deaths, Aug 11, 2021, ” During the deadly heat wave that blanketed Oregon and Washington in late June, about 600 more people died than would have been typical , a review of Mortality data for the week of the crisis shows.”    
comments by Steve Zemke and Rich Ellison
TreePAC and Friends of Seattle’s Urban Forest
March 6,  2023