Reasons to Save Existing Big Trees in Urban Areas

Saving big trees in urban areas is difficult, particularly during development as cities grow in size.. But there are many reasons why saving big trees and planting new trees that will become big over time is important. Excerpts from 3 separate articles  below help to explain why.
Note – The bolding of the text below is mine to help focus on the issue of the value of big trees, not that of the original authors.
1. The Large Tree Argument – the Case for Large-Statue Trees vs Small-Stature Trees , Center for Urban Forest Research, Southern Center for Urban Forestry Research & Information 2004
Large trees pay us back. We now know that, dollar for dollar, large-stature trees … deliver big savings and other benefits we can’t ignore. Small-stature trees like crape myrtle deliver far fewer benefits. In fact, research at The Center for Urban Forest Research shows that their benefits are up to eight times less. Compared to a small-stature tree, a strategically located large-stature tree has a bigger impact on conserving energy, mitigating an urban heat island, and cooling a parking lot. They do more to reduce stormwater run off; extend the life of streets; improve local air, soil and water quality; reduce atmospheric carbon dioxide; provide wildlife habitat; increase property values; enhance the attractiveness of a community; and promote human health and well being.
And when we use large stature trees, the bottom-line benefits are multipliedWhen it comes to trees, size really does matter. Don’t forget the established “Old Guard” We can’t forget the already-established trees. These older trees provide immediate benefits. The investment that community leaders made 30, 40, 50 years ago is producing dividends today. Dr. McPherson, Director of the Center for Urban Forest Research, points out that “since up-front costs to establish these large-stature trees have already been made, keeping these trees healthy and functional is one of the best investments communities can make.”” 
2.  The Struggle to Save Seattle’s Urban Forest in the Face of Development, Seattle Magazine, October 2017, University of Washington social scientist Kathleen Wolf, Ph.D
“Wolf knows this research well, because her own work is focused on how people experience nature in cities, including the human health and economic benefits of the urban forest—the phrase used to describe the trees and understory plants in a city. Forest bathing aside, research shows our health is boosted by having access to urban trees and other nature. “Neighborhood greening reduces depression, may help kids reduce ADHD symptoms, reduces our stress response, encourages physical activity, reduces signs of mental distress, increases cognitive memory, improves air quality and, overall, promotes significantly higher well-being,” she says.

City trees can also raise property values, reduce crime and muffle urban noise. They help the environment, absorbing water, decreasing flooding and the need for water treatment, and absorbing and storing carbon dioxide, directly fighting climate change. “Up until recently, trees really didn’t have a place at the table with city decision making, but now, because we know about their environmental services and the health benefits, trees are an important component of city decision making,” says Wolf. ” ….

Wolf says large trees provide “a much greater proportion of benefit” to cities compared to small trees, in terms of ecosystem services, such as water quality, air quality and carbon sequestration. “Are we going to relegate large trees only to parks and green spaces, or can we incorporate them into development?” she asks. “I’m not sure.”

3.  When it comes to the Climate, Older trees do it Better, Bryan Walsh,, Jan.15, 2014

“…according to a new study published in Nature, it turns out that the oldest trees are actually still growing rapidly, and storing increasing amounts of carbon as they age. An international research group led by Nate Stephenson of the U.S. Geological Survey Western Ecological Research Center reviewed records from forest studies on six continents, involving 673,046 individual trees and more than 400 species, going back as far as 80 years ago. For 97% of the species surveyed, the mass growth rate—literally, the amount of tree in the tree—kept increasing even as the individual tree got older and taller. Even though trees tended to lose leaf density as they aged…the total amount of leaf cover kept increasing as the tree itself got bigger and older. In other words, the number of leaves per cubic foot fell off but the leafy surface area grew and grew. That enabled the tree to keep absorbing an increasing amount of carbon as it aged.For some species of trees, that increase could be enormous. A single big tree could sequester the same amount of new carbon in a year as might be contained in an entire mid-sized tree.”

Washington Native Plant Society editorial on updating Seattle’s Tree Protection Ordinance

WNPS Comments on Seattle City Tree Ordinance

Western hemlock (Tsuga heterophylla). Photo: Ben Legler

Dear Mayor Durkan and Seattle City Councilmembers,

The Washington Native Plant Society commends you for your interest in Seattle’s trees and urges you to work with the Urban Forestry Commission to update Seattle’s tree protection ordinance this year. Our members and leaders have tracked Seattle’s progress toward effective tree protection as the urban tree canopy has continued to disappear.

Further delays of an effective tree protection ordinance increase the detrimental impacts of tree loss on our state’s largest city, a city many of us call home and that Washingtonians treasure. Losing our urban forest means losing the native plants that define the city.

Native trees and shrubs within Seattle’s urban forest create a strong, positive sense of place reflective of the Puget Sound region’s natural richness. These green oases also contribute to a healthy environment for people; they provide restorative, educational, and recreational opportunities for residents and visitors.

Our hemlocks, firs, and cedars provide habitat for birds and other wildlife that are disappearing in alarming numbers. Exceptional and heritage trees, grouped and individual, are the irreplaceable foundation of the urban forest. These established trees add economic value to urban neighborhoods. These trees ensure that neighborhoods are livable.

Douglas fir (Pseudotsuga menziesii). Photo: Ben Legler

Trees are a front line defense against and mitigation for climate change. Over the next 50 years, even with aggressive emissions reductions, temperatures will more than double Seattle’s days of extreme heat (pers. comm., June 24, 2019, Marcia Brown, Anthropogenic Warming and Public Health Consequences in Seattle and Spokane, University of Washington).

The presence of trees reduces local temperatures. Trees are a cost-effective way of cleaning smoke from the air. With increased smoke from wildfires, it is imperative to preserve and protect mature trees within our state’s cities. Trees also help control the stormwater resulting from heavier rainfalls. We need to increase the urban canopy, not stand by while it dwindles to nothing.

Protecting trees within urban areas contributes to environmental justice within the city as well as to regional ecologic health. Mature trees benefit the most vulnerable—residents without access to shelter and air conditioning, children walking to school, and elders out exercising. Protecting trees does not preclude dense development. Vancouver, to the north, has both significantly more trees and higher population density.

It would be a shame for Seattle, the Emerald City, to lose its trees. We must protect the trees we have now, as well as planting saplings that will shade future generations.

Among Seattle residents there is strong support for a robust urban forest, and for government that protects the city’s exceptional and heritage trees. Washington Native Plant Society members, many of whom volunteer in city parks and green spaces, understand that the tree canopy contributes to the public good and can’t be quickly replaced.

Western red cedar (Thuja plicata). Photo: Ben Legler

As our member Michael Marsh so aptly put it, “An exact parallel to removing a 70-year-old tree and replacing it with two saplings would be replacing an experienced City Council Member with two 3-year-olds.” We trust that you understand. The current rate of loss is unacceptable and fails to take into account the many benefits of trees.

The Washington Native Plant Society and our Central Puget Sound Chapter urge you to slow and reverse Seattle’s tree loss by updating the tree protection ordinance this year.

WNPS Editor’s Note 2: If you are interested in learning more about the Seattle Tree Ordinance, these three groups will help you follow it: Friends of Urban ForestsDon’t Clearcut Seattle, and TreePAC. You may also want to learn about the Last 6,000 Campaign, which aims to locate Seattle’s remaining majestic trees.

Not in Seattle? The benefits of urban and community forests stretch beyond the city limits. The website of the Washington State Urban And Community Forestry Program is a good starting place to learn more about how trees provide economic, environmental, psychological, and aesthetic benefits. The program can provide assistance for planting and sustaining healthy trees and vegetation. Similarly, the U.S. Forest Service Urban and Community Forestry Program provides a national lens on the subject. 

Friends of Seattle’s Urban Forest Note – You can support the efforts of the Washington Native Plant Society by donating or becoming a member. Go to

Organizations Supporting Resolution in Support of the Seattle Urban Forestry Commission’s Draft Tree and Urban Forest Protection Ordinance

Submit your Group’s Resolution of Support

Seattle’s current tree ordinance is outdated and failing to protect our urban forest. The Seattle Urban Forestry Commission (UFC) has submitted their recommended updates to the Mayor and City Council.

Let the Mayor, City Council and council candidates know that your group supports the UFC’s draft Tree and Urban Forest Protection ordinance.

List of organizations that have endorsed the Resolution: 

32nd District Democrats

34th District Democrats

36th District Democrats

43rd District Democrats

46th District Democrats

Friends of Seattle’s Urban Forest

King County Democrats

Mt Baker Meaningful Movies

Neighborhood Treekeepers

Seattle Green Spaces Coalition

South Seattle Climate Action Network

Tree PAC

Seattle Again Delays Enacting New Tree Protection Ordinance

Coalition for a Stronger Tree Ordinance

Seattle Again Delays Enacting New Tree Protection Ordinance

Dear Tree Protection Advocates,

Unfortunately once again the Seattle City Council and Mayor are doing what they have done for the last ten years. They are again, while trees continue to be cut down, opting for more studies rather than passing an updated Tree Protection Ordinance now. We already know the tree ordinance isn’t working to save trees according to the City’s  recent Tree Regulations Research Project Report and other information.

The  Seattle Urban Forestry Commission has been working for the last 10 years  providing the Mayor and City Council  with recommendations and in June, at the Council’s request, provided them with a draft ordinance update based on these recommendations and recent Council resolutions on what should be addressed.  Rather than consider this draft, they want to start over.

On Wednesday, Sept 11, 2019, the Council Finance and Neighborhoods Committee will meet from 2-4 PM in Council chamber to discuss and pass another resolution: 

Res 31902 A RESOLUTION declaring the City Council’s and the Mayor’s intent to consider strategies to protect trees and increase Seattle’s tree canopy cover. 
Central Staff Memo
Summary and Fiscal Note

Rather than starting  over we urge the Council to consider adopting, after review, the Urban Forestry Commission’s June 2019 draft Tree and Urban Forest Protection Ordinance.

Here is the Draft Urban Forestry Commission’s Ordinance:
Tree and Urban Forest Protection Ordinance  

You can send the Mayor and City Council a quick e-mail urging they adopt the Urban Forestry Commission’s draft Tree and Urban Forest Protection Ordinance.  We have lost enough trees in Seattle already.  We do not need more studies for another year as trees continue to be cut down every day.

Go to 
Send an e-mail by clicking on the Take Action button.
Add your own comments to personalize the message.

Steve Zemke

Chair – Coalition for a Stronger Tree Ordinance – a Project of Friends of Seattle’s Urban Forest and TreePAC.

PS  Help is needed now with donations to fund our campaign.
Click on the donate link below to give a campaign donation via to help update the tree ordinance. Money will help pay for yard signs, printing and other expenses.Thanks.

  Donate here


Friends of Seattle’s Urban Forest 
Tree PAC
Don’t Clearcut Seattle


Continue reading

Resolution urging passage of Seattle UFC draft Tree and Urban Forest Protection Ordinance

Resolution in Support of Seattle Urban Forestry Commission’s 

 Draft Tree and Urban Forest Protection Ordinance

Whereas Seattle is not only losing its big trees but many others as developers frequently are scraping lots clean of trees to maximize their building sites, and

Whereas Seattle is not requiring developers to replace all exceptional trees and trees over 24” DBH (diameter at 54” high) removed, as prescribed by SMC 25.11.090, and

Whereas, unlike Portland and other major cities, Seattle has not instituted a Tree Removal and Replacement permit system on either developed property or property being developed but only relies on a complaint-based system on developed property that is not protecting trees, and

Whereas the Seattle City Council (“the Council”) voted in 2009 and again in Resolution 31870 in April 2019 to support updating its Tree Protection Ordinance,and

Whereas in 2017 in its Tree Regulations Research Report, the city  found that “Current code is not supporting tree protection” and “we are losing exceptional trees (and groves) in general.”, and

Whereas Seattle’s trees and urban forest are vital green infrastructure in Seattle that reduces air pollution and stormwater runoff, reduces climate change impacts like heat island effects, provides essential habitat for birds and other wildlife, and is important for both physical and mental health for people living in Seattle, and

Whereas the Seattle Urban Forestry Commission has drafted, at the suggestion of several Council members, an updated Tree Protection Ordinance that is consistent with the eight recommendations the Council adopted in Section 6 of Resolution 31870 in April 2019, and

Whereas the draft ordinance would:

  1. Increase protections for Seattle trees and tree canopy volume by requiring tree removal and replacement permits for all significant trees (over 6” DBH) removed on both developed property and property being developed on all land use zones in the city;
  2. Require 2 week posting of tree removal and replacement applications on site as SDOT does;
  3. Require  tree replacement on site, which in 25 years, is equivalent to the tree canopy volume removed or require a fee paid into a Tree Replacement and Preservation Fund to plant and maintain for 5 years the trees elsewhere in the city;
  4. Retain current protections for exceptional trees and reduce upper threshold for exceptional trees to 24” DBH;
  5. Allow no more than 2 significant non-exceptional trees to be removed over 3 years on developed property;
  6. Require registration of all tree services providers with the city;
  7. Track all significant tree loss and replacement; and
  8. Provide adequate funds to administer and enforce the ordinance.

Therefore, be it resolved that we support the efforts of the Coalition for a Stronger Tree Ordinance to update and strengthen Seattle’s current ordinance. We urge the Mayor and Seattle City Council to pass the Seattle Urban Forestry Commission’s June 15, 2019 draft Tree and Urban Forest Protection Ordinance and to enforce it.

Please let the Mayor and City Council know that your organization has adopted this resolution. Send your message easily and quickly by going to and click on the link “Organizational Support”

We will also add your organization’s name to our list of organizations supporting adopting the Seattle Urban Forestry Commission’s draft Tree and Urban Forest Protection Ordinance.


Action Needed Now on Draft Tree Protection Ordinance

Action Needed Now to Protect Seattle’s Trees and Urban Forest

Urge Mayor Jenny Durkan and Seattle City Council members to provide strong leadership now to pass legislation this year to significantly strengthen Seattle’s current Tree Protection Ordinance.

Seattle’s urban forest is an integral and vital part of our city.  It provides many benefits and amenities to those living in our city. Research has shown that retaining existing trees and planting new trees is one of the best ways to mitigate our climate crisis.    Trees help clean our air and enhance public health, reduce stormwater runoff, decrease the impacts of heat and wind, provide habitat for birds and wildlife and give us a connection with nature in our neighborhoods.

Seattle’s rapid growth is reducing these beneficial impacts as trees are removed. It is urgent that Seattle act now to stop the continued loss of trees, particularly large trees and exceptional trees and tree groves, and to promote environmental equity as we replace and plant more trees to increase our tree canopy.

Urge the Mayor and City Council to adopt the draft revisions for the Tree and Urban Forest Protection Ordinance that the Seattle Urban Forestry Commission submitted in June 2019 to Councilmember Sally Bagshaw and the Seattle City Council. The updated draft would:

  1. Expand the existing tree removal and replacement permit program, including 2-week public notice and posting, as used by the Seattle Department of transportation (SDOT) – to cover all trees 6” DBH and larger on private property in all land use zones, both during development and outside development.
  2. Require the replacement of all trees removed that are 6” DBH and larger with trees that in 25 years will reach equivalent canopy volume – either on site or pay an in-lieu fee into a City Tree Replacement and Preservation Fund. Allow the Fund to also accept fines, donations, grants and set up easements.
  3. Retain current protections for Exceptional Trees and reduce the upper threshold for exceptional trees to 24” DBH, protect tree groves and prohibit trees over 6”DBH being removed on undeveloped lots. 
  4. Allow removal of no more than 2  significant non-exceptional trees in 3 years per lot outside development
  5. Establish one citywide database for applying for tree removal and replacement permits and to track changes in the tree canopy.  Post online all permit requests and permit approvals for public viewing.
  6. Expand SDOT’s existing tree service provider’s registration and certification to include all tree service providers working on trees in Seattle.
  7. Provide adequate funding in the budget to implement and enforce the updated ordinance.

Please let the Mayor and City Council know you support the 7 items above as recommended by the Seattle Urban Forestry Commission by copying  and pasting them in an email to send to the Mayor and Seattle City Council in support of updating Seattle’s Tree Protection Ordinance. They need to hear from you. Add your own personal comments and reasons for support.

Send to,

 and to the Seattle Urban Forestry Commission for posting as public comment  on the UFC draft ordinance –

Thank you for your help.

Coalition for a Stronger Tree Ordinance

Good News – Tree Protection Ordinance Update this Year is a GO!

Coalition for a Stronger Tree Ordinance
Dear Tree Protection Advocates,

We have passed a big hurdle. On Wednesday Councilmember Sally Bagshaw came to the Seattle Urban Forestry Commission. She told the Commission that she met with Mayor Jenny Durkan on Monday. Mayor Durkan has agreed to move forward this year with  Councilmember Bagshaw and the City Council on working to pass an update to SMC 25.11 – the Tree  Protection Ordinance.

The tentative schedule will be a very tight one. But things are coming together and if we continue to let the Council and Mayor know that the people in Seattle urgently want a stronger tree ordinance that works, we can make it happen!

So one first step is to thank Mayor Durkan and Councilmember Sally Bagshaw for moving this legislation forward now. Thank them by sending an e-mail to: and

A key component was the work of the Seattle Urban Forestry Commission (UFC) in providing a draft revision of the Council’s last tree ordinance draft to Councilmember Sally Bagshaw as she requested. When Councilmember Bagshaw was asked on Wednesday if she saw any problems with the draft, she responded with a no. She gave the UFC  permission to  circulate the  UFC draft and here it is. The first 5 pages of the document below is an outline of what is in the draft, followed by the actual UFC draft ordinance.

Draft UFC revision to Council D7 draft – Tree Regulations:
Tree and Urban Forest Protection and Land Use Regulations

The plan moving forward is for the Council and City Departments to review the draft, have the City Attorney review the draft, complete a SEPA review, file the draft with the Council Budget and Neighborhood Committee chaired by Councilmember Bagshaw by the beginning of September, circulate the draft for public comment including holding  forums in September in both North and South Seattle, put adequate  funding in the budget to fund implementation of the ordinance  and pass the Legislation in the first two weeks of December after the budget is adopted.

So there are a lot of steps in this process, but it is moving. We can do this but we need to coordinate our efforts as tree advocates so that we can speak in unison and work in unison to be most effective.

Join us at our meeting tomorrow Sat. July 6th to discuss the next steps.

Coalition for a Stronger Tree Ordinance
Campaign Planning Workshop on Updating  Seattle’s Tree Protection Ordinance in 2019 
Saturday July 6, 2019 10:15 AM to 12:15 PM
Broadview Library, 12755 Greenwood  Ave NE, Seattle, WA

Also help is needed now with  donations to fund our campaign.
Click on this link to give a campaign donation to  update the tree ordinance via today. Thanks

  Donate here

Steve Zemke

Chair – Coalition for a Stronger Tree Ordinance – a Project of Friends of Seattle’s Urban Forest and TreePAC.

websites – and

facebook – Friends of Seattle’s Urban Forest  and facebook – Tree PAC

Seattle Urban Forestry Commission submits Draft Tree Protection Ordinance Update to Council

Seattle City Councilmember Sally Bagshaw to Champion Tree Protection Ordinance Update

Seattle City Councilmember Sally Bagshaw, who Chairs the Finance and Neighborhoods Committee, has agreed to pick up the effort to update Seattle’s Tree Protection Ordinance. The legislation was being pushed by Councilmember Rob Johnson for the last year and a half. Johnson resigned earlier this year after the Seattle City Council passed the Mandatory Housing Affordability Ordinance he was pushing.

Councilmember Bagshaw met with the Seattle Urban Forestry Commission last month and urged them to send her a draft for her to consider. On June 14, 2019 four members of the Urban Forestry Commission met with her – Weston Brinkley the UFC Chair, Stuart Niven – Arborist, Josh Morris – NGO position (Seattle Audubon) and Steve Zemke -Wildlife Biologist. (Sandra Whiting -Urban Ecologist had also participated in the drafting but was not present).  They presented Councilmember Bagshaw  with the draft they had prepared.

Draft – Tree and Urban Forest and Land Use Regulations.

Outline of UFC Draft Tree and Urban Forestry and Land Use Regulations June 14, 2019 draft

Seattle’s Tree Ordinance on the Move Again

Coalition for a Stronger Tree Ordinance
Seattle’s Tree Protection Ordinance Update is on the move again. Councilmember Sally Bagshaw has agreed to move this legislation forward, after Councilmember Rob Johnson resigned from the Seattle City Council earlier this year.

Councilmember Bagshaw met with the Seattle Urban Forestry Commission last month and asked them to produce a draft update of the ordinance. A new draft is being finalized, based on the Seattle City Council’s previous work, the current ordinance,  the Seattle Urban Forestry Commission’s  work and the issues the City Council agreed with in the accompanying City Council Resolution passed  as part of the MHA Ordinance.

A drafting committee of the Seattle Urban Forestry Commission will be presenting their draft to Councilmember Bagshaw and Council staff on Friday June 14, 2019.

The Coalition for a Stronger Tree Ordinance will be meeting the next day, Saturday, June 15th, to discuss what’s in the draft and what comes next. You’re invited to come and participate in the discussion.

Coalition for a Stronger Tree Ordinance
Briefing on Tree Protection Ordinance Update
Saturday June 15, 2019 10:30 AM to 12:30 PM
Lake City Library, 12501 28th Ave NE, Seattle, WA

Looking forward to seeing you Saturday..

Steve Zemke

Chair – Coalition for a Stronger Tree Ordinance – a Project of Friends of Seattle’s Urban Forest and TreePAC.


New Tree Rules for Single-Family Homes in Seattle

New Tree Rules for Single-Family Zones

Large treeOn April 19, new rules went into effect for tree planting and protection requirements in single-family zones. The recently passed Mandatory Housing Affordability Ordinance 125791 made several important changes to tree protection requirements in the Seattle Municipal Code (SMC) 25.11, Tree Protection, and SMC 23.44, Single Family Zone. Those changes are:

  1. SMC 25.11.040, Restrictions on Tree Removal, no longer includes an exemption from the exceptional tree designation or from requirements for tree removal on single-family lots less than 5,000 square feet. The exceptional tree rules now apply to all sizes of lots in single-family zones, including the residential small lot category. Trees can now be removed only under the same criteria that apply to lots greater than 5,000 square feet.
  2. The residential small lot (RSL) zone is now a part of SMC 23.44, Residential, Single-Family.
  3. The tree planting, retention, and protection requirements for single-family zones, formerly located in SMC 23.44.008.I, are now in a new section, SMC 23.44.020.  The “caliper inch” planting or retention requirement for lots zoned as single-family 5,000, 7,200, and 9,600 remain the same (SMC 23.44.020.A).  Planting or tree retention requirements for RSL lots is different. It is based on a point system and providing street trees is now required (SMC 23.44.020.B).  Unlike the other three single-family zones where street trees can be counted toward the planting or retention requirement, street trees are not counted toward the on-site requirement in RSL zones.

For more information about tree protection rules, see our Tree Protection Code webpage.

article copied from SDCI website  – New Rules for Single-Family Zones