Saving our Urban Forests – A Small Step Forward

mt davidson understoryThis article is republished from the Death of a Million Trees website with permission and minor edits.

The San Francisco Forest Alliance (SFFA) has announced (see below) the successful conclusion of a year-long process of developing a policy for the management of San Francisco’s urban forest by the city’s Urban Forestry Council (UFC). If you have not been closely following the development of this policy it may be difficult to appreciate the importance of this accomplishment.

Native plant advocates made every effort to prevent the UFC from adopting a policy that would make a commitment to the preservation of the urban forest. As our readers know, native plant advocates want the entire urban forest to be destroyed because it is non-native, so they can attempt to recreate native grassland and scrub that existed at the end of the 18th century, prior to the arrival of Europeans.


Native plant advocates tried several different strategies to make the case to the UFC for the destruction of the forest. This is the sequence of the many bogus narratives they attempted to sell to the UFC:

  • They started with the claim that the forest is diseased and dying and must be destroyed. With the help of arborists and our usual independent research, we were able to disprove this particular story line.
  • Then they claimed that forest health would be improved by radical thinning of the forest. Again, our research was able to prove that mature forests do not benefit from thinning because mature trees are unable to respond positively to increased light and wind. The trees that remain are actually more vulnerable to windthrow because they are not adapted to increased wind.
  • Then they claimed that the forest is dying of drought and must be destroyed to prevent the dead trees from becoming a fire hazard. Again, our research was able to prove that our eucalyptus forest is drought-tolerant and is actually more likely to survive the drought than the native plants which will not precipitate as much fog drip as tall trees. However, the final document contains an erroneous claim that the drought has “serious negative effects to mature trees.” In fact, young trees require more water than mature trees.

In December 2014, after listening to six months of these horror stories, it seemed that the UFC was headed in the wrong direction. Their questions and comments, as well as the meetings we were able to arrange, seemed to indicate they were prepared to endorse the destruction of our urban forest. In January 2015, the first draft of the UFC policy confirmed our worst fears. They endorsed “land conversion” from forest to native grassland and scrub and the use of herbicides to prevent the resprouting of the forest.


Having done everything we could to prevent this outcome, we despaired. And then the UFC produced a revised draft in April 2015 which was a 180-degree turn from the first draft. We will never know what turned the UFC around, but we surely had a hand in it. Even if there was some unseen influence operating in the background, our viewpoint was confirmed and vindicated by the final outcome.

The UFC then postponed approval of their document, saying they were waiting for public comments from one of the stakeholders. I presume this delay was requested by the Recreation and Park Department, because the final revision of the document accommodated its so-called Natural Areas Program by stating that “management priorities and decisions for some of the mature and historic tree stands [within the “natural areas”] may be different from management practices for other areas of the urban forest.” However, written comments from the Recreation and Park Department were not visible to us.

We are taking the time to tell you about this accomplishment because we hope you will be encouraged by it. Sometimes the odds seem overwhelmingly against our efforts to save our urban forest. But with tenacity and commitment, it is possible to prevent bad things from happening. We are deeply grateful to those who participated in this successful effort to prevent the development of an official city policy that could have endorsed the destruction of our urban forest.

Much remains to be done. Do not give up hope that we can save our urban forest. Please renew your commitment to our efforts.



Greetings to SFFA Supporters and Members

This week the Urban Forestry Council of the Dept. of Environment accepted a document now called“Guidelines for Managing Mature and Historic Tree Stands,” which had originally been called “Best Management Practices for Urban Forests.” It was written largely by John Leffingwell of HORT Science who sits on the Council, with assistance from Mei Ling Hui, staff member from Dept. of Environment; John Flanagan, Chair of the Council; and Igor Lacan, who also sits on the Council and works for the San Mateo-San Francisco Cooperative Extension service.

[You can also read it here: draft_guiding_principles_for_mature_and_historic_tree_stands_6_16_15]

The document went through several iterations, starting back with its first draft in January 2015, which followed six months of meetings and presentations in 2014. By April 2015 it had been completely revised and had moved away from its earlier endorsement of restoration ecology and the native plant agenda of destroying blue gum eucalyptus forests. Unfortunately, it was passed including one section called “Competing Land Use Priorities” that provides a disclaimer for the Natural Areas Program to treat its trees differently than other urban forests in the name of “protecting San Francisco’s ‘remnant fragments’ of its original landscape.” That section could, at some later date, be used by Rec and Park as endorsement of their destructive plans in the Natural Areas.

However, there is much in the document that would mitigate against that destruction, including a section called “Protect and sustain iconic forest stands.” This section argues that our mature and historic tree stands “are character defining features of the city that provide unique experiences to those who enjoy them” and should be “protected and managed for their cultural and social benefits to residents and visitors.” Their importance is “evidenced by community groups formed around the protection and management of these sites” [Note: that would probably mean the SF Forest Alliance and Concerned Citizens for the Maintenance Alternative.] Although this document may not sound important, it is. It will be used as a guideline by the Urban Forestry Council whenever issues or plans related to the urban forests are brought before them. Potentially, the Board of Supervisors might refer to it as well when there is an appeal of the EIR for the Natural Areas Program’s management plan.

It took a year’s worth of volunteer hours from SF Forest Alliance leaders who attended meetings, made comments and presentations. Additionally, others, including Dr. Joe R. McBride and members of the Hills Conservation Network made presentations before the Council supporting our point of view.

We see it as a small step in the right direction.

Thanks for your continued support!

San Francisco Forest Alliance


1) We encourage you to visit our Blog at Enter your email address as the top right (“sign me up”) in order to receive our updates directly to our email.

2) If you’re on Facebook, please “Like” our page Alliance. We currently have 424 “likes.” Help us to take it over 450!

3) We can be reached at this email address:

We welcome your interest and support!

Wishing You All a Good 2015!

The year end 2014 marked the third full year for this site, which was started in December of 2011. Now we’re well into the beginning of 2015 and the continuing fight to save our forests and natural spaces for the sake of the environment and for families who visit these places.

We’d like to wish all our readers a great year ahead by reprising these children’s drawings that we first posted in January 2014.

Save-the-Eucalyptus sm

Save the Eucalyptus by Desiree Minkler

the-morning-before-the-loggers-came sm

The Morning Before the Loggers Came – Desiree Minkler


Whoos For Us? – Tacy Prins Woodlief

no-more-homeless-owls sm

No More Homeless Owls – Blake Bogert


Poisoned Water – Ayumi Beeler

Why Urban Trees Are Important to Us All

Recently, we wrote about the importance of setting a tree canopy cover goal for San Francisco, a city that should be a green leader. We’d like to see such a goal incorporated into the Urban Forest Master Plan, which unfortunately watered down its goals from the first public draft. San Francisco has an tree canopy cover percentage of only 13.7% – as against an ideal of 25%. (We’re writing to the Planning Commission at  – and if you would like to add your voice, please do the same. Tell them the Urban Forest Master Plan needs a canopy cover goal!)

Mt D 6-17-2013

Urban trees are a public asset. They benefit us all in many ways: Green infrastructure; fighting climate change; improved public health; reducing crime; improving economic values.  Recently, we found an excellent note from Alliance for Community Trees (ACTrees) that compiled all these benefits – and documented the scientific data. We’re summarizing and including the PDF with permission.

You can read it here as a PDF:  benefits_of_trees – Actrees  There’s 19 pages of  information in bullet  points.


This is based on the note from ACTrees, using excerpts and summaries to bring out key points.

  1. Economic benefits:  The 3.8 billion trees in the US have a structural asset value of around $2.4 trillion.
  2. Reducing storm water runoff and maintenance costs: Urban forest can reduce storm water runoff by 2-7%, and a mature tree can store 50-100 gallons of water during storms. Portland is planting 4,000 trees to implement a gray-green storm water management solution – and saving $64 million.
  3. Improving air quality: Trees clean the air by absorbing carbon dioxide, sulphur dioxide, nitrous oxides, and trapping particulates.
  4. Improving water and soil quality: Trees divert captured rainwater into the soil, where micro-organisms filter out impurities. Trees can also help remediate contaminated soil, absorbing many contaminants.
  1. Improving attention: Kids with Attention Deficit Disorder function better in green settings – as do college students in dorms with a green outlook.
  2. Decreasing asthma and obesity: Columbia University researchers found that asthma rates fell by 25% for every extra 340 trees per square kilometer [247 acres]. Kids in greener neighborhoods have a lower Body Mass Index.
  3. Improving physical and mental health: Visual exposure to settings with trees helps recovery from stress within 5 minutes. And in one study, workers without nature views from their desks claimed 23% more sick days.
  4. Reducing hospital days: Patients in post-op recovery had shorter hospital stays and needed less pain medicine if they had green views, compared with rooms facing a brick wall.
  5. Protection from Ultra-violet rays: A person takes 20 minutes to burn in full sun, but 50 minutes in part shade, and 100 minutes in full shade.
  6. Noise reduction: Trees absorb noise. A belt of trees 98 feet wide and 49 feet tall can reduce highway sound by 6-10 decibels.
  1. Traffic calming and accident reduction: Trees improve driving safety. One study found a 46% decrease in crash rates after landscape improvements were installed. Drivers reduce speeds by an average of 3 miles per hour in the presence of trees. Trees can also reduce road rage by reducing stress.
  2. Reducing road maintenance costs: Trees prolong pavement life. Shaded roads can save up to 60% of paving costs.
  1. Business districts – Increased sales, desirability, and rents: Shoppers prefer districts with high-quality trees, and spend more time there. They are willing to pay 7-10% higher prices. Commercial offices with trees have a 7% higher rent.
  2. Jobs: In 2002, distributing, planting, and maintaining trees added about 2 million jobs. [Now – it can only be higher.]
  1. Increasing property values: Studies have found up to 37% increase in residential values.
  1. Storing carbon and reduction of carbon emissions: Urban trees in the US store 700 million tons of carbon, and sequester 22.8 million tons of carbon per year. Urban trees sequester more carbon than wild forests because they grow faster. In California, if 50 million trees were planted, they would sequester 4.5 million tons of CO2 annually, and could reduce air-conditioning energy use equivalent to 1.4 million ton of CO2 in addition. That would be like retrofitting every household with energy-efficient devices.
  2. Carbon mitigation programs: In Los Angeles, the ‘Million Trees LA” campaign plans to plant one million trees, aiming to reduce carbon equivalent to taking 7,000 cars off the street each year.
  3. Reducing the heat island effect: Trees reduce the heat island effect. Shaded surfaces may be 20-45 degrees F cooler than unshaded ones. Trees cool city heat islands by10-20 degrees, reducing ozone levels and helping cities meet air quality standards.
  1. Trees reduce energy consumption: Trees can reduce both cooling and heating costs by providing shade and acting as windbreaks. A 25-foot tree can reduce annual heating and cooling costs of a typical residence by 8-12%.
  1. Less violence and crime: Public housing with nearby trees and nature reported 25% fewer acts of violence. Apartment buildings with high levels of greenery had 52% fewer crimes than those without any trees.
  2. Improves community: In buildings with trees, people report significantly better relations with their neighbors. People report a stronger feeling of unity and cohesion with their neighbors.
  3. Wildlife and biodiversity: Urban forests help create and enhance animal and bird habitat.


How much tree cover a city needs depends on local climate. Eastern cities ideally need 40% and western cities need 25% canopy cover.

[San Francisco has 13.7%, a city estimate updated from USDA’s 2007 estimate of 11.9% using a different methodology. We will summarize the excellent USDA report on San Francisco’s Urban trees another time, but you can read the whole report here: SF Urban Forest fs fed US]

felled trees 015

Bees in Glen Canyon – Update

 We’ve reported here before about the bee tree that was cut down as part of the “improvements” to Glen Canyon Park – and the one that was killed by mistake when someone thought it was a nest of yellow-jackets, not bees. This meant that only one of the three wild bee trees was still a living hive. We recently had both good news and bad news. There’s still only one bee tree, but the bees have proved resilient.

Karen Peteros wrote this note, which is published with permission. [This was originally published at Save the Trees of Glen Canyon Park.]


Scott Mattoon and I have been working with RPD [San Francisco Recreation and Parks Department] Capital Improvements since 2011 to minimize adverse impacts Glen Canyon Park improvements could have on our feral honey bee colonies.

exposed hive with bees (Photo- Scott Mattoon)

Exposed hive with bees (Photo – Scott Mattoon)

One bee tree was lost on the hill above the Rec Center. Despite many many meetings with RPD, and a negotiated agreement to cut that bee tree at 25′ and otherwise leave it alone, the subcontractor failed to get that instruction and cut the tree at 5′. The trunk split and the colony exposed, but I was able to save the remaining bees and queen and install them in a Langstroth hive.

The bee tree that Scott discovered to have had its hive opening spray-foamed shut a few years back (above where Islais Creek goes underground) due to mistaken identification as a culprit of a nearby sting incident, seems to have reopened and a swarm moved in last year. That colony has done well, and recently swarmed (I understand Philip Gerrie retrieved the swarm).

revived hive

Revived hive – Photo (c) Janet Kessler

the bee tree that was killed has bees again

The bee tree that was killed has bees again. Photo (c) Janet Kessler

After many discussions, emails and meetings with RPD, Scott and I have convinced RPD to leave that tree alone for now. It has a substantial lean but, if it were to fall, it would not cross the path especially if RPD would cut off the top limbs right above the crotch where the limbs grow out of the main trunk. That’s been our recommendation but it has not yet been done to reduce the risks if it were to fall.

As usual RPD does what it wants — under-doing things by not cutting the limbs to reduce the risks if the tree were to fall which has been their stated concern but also over-doing things by placing the orange fence around the tree unreasonably suggesting the bees are a safety hazard when they are not. Nonetheless, the orange fence has served to be educational to bring park goers’ attention to honey bees in a natural habitat.

Finally, the very large mother bee tree, fenced down near Silvertree, with the opening in the base is undisturbed but the colony died out after many years of perpetuating itself.

I have not seen any bee activity there since late last year. 

the remaining bee tree

The old bee tree. Photo (c) Janet Kessler

Give the wax moths another year or more and, hopefully, the cavity will be cleaned out sufficiently to be deemed suitable by a future swarm looking to set up residence.

Karen Peteros,
Glen Park neighborhood resident & beekeeper
San Francisco Bee-Cause

Opposing ROSE’s Policy 4.2 – Update

[UPDATE: Disappointingly, despite what we were told was a deluge of emails and phone calls, the Board of Supervisors passed the ROSE – including Policy 4.2. Details are available here: The ROSE disappointment.]

Two weeks ago, we explained why we oppose the ROSE (Recreation and Open Space Element of the General Plan for the city of San Francisco), and asked San Franciscans to write to the Land Use Committee of the Board of Supervisors. The main issue is that the draft ROSE includes Policy 4.2, which potentially could extend the same principles as the Natural Areas Program (i.e. cutting down trees, restricting access, using toxic herbicides, all to favor Native Plant museums) to all the city’s Open Spaces.

Here’s an update.

  • The Land Use Committee decided not to decide. Thanks to your emails and phone calls, the three Supervisors on the Land Use Committee grew concerned about the issue. Though they did not vote NO on the ROSE, they did not vote yes either. Instead, they passed it on to the full Board of Supervisors without a recommendation. The Board was expected to vote on June 24th, 2014.
  • The Full Board postponed the vote to July 8th, 2014. Because of the uproar against the ROSE, the Board decided to postpone the vote for two weeks, until July 8. Supervisor Scott Wiener (District 8) said that some of his colleagues had not been “briefed” on the ROSE. We are not sure if that means briefed by one of the city departments that is hoping to push the ROSE through with the egregious Policy 4.2 still included; or if they wish to take the time to understand the concerns of those so vehemently opposed.

The good news is this gives us more time to get even more people to ask them to Vote NO on the ROSE. The West of Twin Peaks Central Council voted this week to send a letter urging the Supervisors to Vote NO on the ROSE. Others are trying to visit the supervisors to brief them from our point of view. We encourage you to write (e-mail) and/or call your Supervisor to urge him/her to enter a no vote on July 8th.

The Natural Areas Program is a really bad model to extend all over the city. Even within its current bounds, it generates enormous controversy, quite disproportionate to its size. There is no reason to use the same principles elsewhere.


Watch our video on Youtube, (where you can also sign up for the SF Forest Alliance Youtube channel):


What we stand for can be summarized in four key areasTreesAccessToxinsTaxes.

This is an opportunity for the Supervisors to stop something that would be bad for our city, for residents and families, and wildlife. It would build conflict into the General Plan, possibly for decades.

The San Francisco Forest Alliance asks the Supervisors to vote NO on the ROSE, to send it back to Planning until Policy 4.2 is removed. We’re a grass-roots organization of people who love nature and the environment, pay taxes responsibly, and want access to our parks and wild places – with our families.

Citizens care about their city Parks, and want to keep healthy trees and to open access to natural areas. Citizens expect city management to act responsibly and in the public trust.

Supporting “Clean, Green and Safe” from Scott Wiener

tree preservation zone madison WI

Tree preservation zone, Madison WI – Perhaps San Francisco can do this too?

We’re asking the Board of Supervisors at San Francisco’s City Hall to support Supervisor Scott Wiener’s “Clean, Green and Safe” budget package. Here’s what he’s proposing (this is taken from a note from his office):

  • $2 million to increase tree maintenance in our parks (Recreation and Parks Department). Rec and Park has only enough staff to maintain an average of 750 trees per year – out of a total of 131,000 trees in our parks. With an aging tree population, we are approaching a crisis of hazardous tree conditions in our parks. This funding will allow Rec and Park to increase tree maintenance to address hazardous tree conditions before these trees cause damage or injury and to better ensure the long-term health of all park trees.
  • $2.6 million to expand Park Patrol (Recreation and Parks Department). Currently, there are no more than two Park Rangers per shift to patrol all 220 of San Francisco’s parks. The increase in patrol officers would provide one dedicated Park Ranger on 24/7 patrol for each of the six Park Service Areas throughout the city. With more coverage of our parks, Park Rangers will be better equipped to enforce park rules and address the nearly $1 million in graffiti, property damage, and illegal dumping that occurs in our parks every year.
  • $2.7 million to landscape maintenance and cleaning in our public spaces (Department of Public Works). Years of staffing cuts have left DPW with insufficient personnel to keep our streets, sidewalks, and public spaces clean and our green landscaping thriving. Getting the debris and waste cleaned off our sidewalks and out of our public spaces is a primary responsibility of city government. These funds will increase landscape maintenance staff and cleaning crews to make our neighborhoods cleaner and healthier.


Here’s our letter to the Board of Supervisors:

The San Francisco Forest Alliance urges you to support Supervisor Wiener’s “Green, Clean and Safe” budget package.

We hope this proposal will help to address the need to maintain our park and Natural Areas trees, and thus preserve them rather than allowing them to deteriorate and then using contractors to cut them down when Capital funds become available.

Maintaining the trees in our forests and our parks – and planting new ones – will help the city maintain and expand its tree canopy, which in turn reduces pollution, provides fresh air, battles global warming through carbon sequestration, and provides a habitat for hundreds of species of birds and animals. Research has shown that trees improve human health, and that when urban forests are destroyed, death rates rise.

We also hope that this would fund park patrols particularly at night, thus reducing vandalism in our parks, and making them safer for everyone. It should also enable the city to clean up, maintain, and police our urban parks and plazas that fall into disrepair and misuse.


Carolyn Johnston, President, San Francisco Forest Alliance

Open Letter to SF Weekly

Recently, journalist Rachel Swan saw our post Fighting the NAP Nativist Agenda and our video caught her attention. (Here’s  our video on Youtube, where you can also sign up for the SF Forest Alliance Youtube channel)

She  had some questions for us for an article she intended to write for SF Weekly. We sent her an email in response. Of course,  she didn’t repeat it in her short and hard-hitting article, but we thought our readers might be interested in seeing what we said. We’ve put it in this open letter to SF Weekly.


Dear SF Weekly,

Thank you for reporting on the rift within the environmental community, and to Rachel Swan for planning the article. This is something too few San Franciscans are aware of.

(We hope we’re not actually slinging mud when we oppose the destruction of trees, use of toxic herbicides, and access restrictions in our parks. We think it’s possible to oppose the Nativist Agenda in the strongest terms while being respectful of the people who support it.)

Your reporter sent us a few questions, which we answered at some length. Obviously she couldn’t include all of that in the article. But we’d like to share it with our readers, and perhaps you would like to share it with yours.


Her first question was what plant we thought was being preserved in Glen Canyon Park, justifying herbicides and tree-cutting?

We don’t actually think the tree-cutting and herbicide application in Glen Canyon is targeted at preserving any specific native plant. Instead, it’s a more generalized preference for “native” plants, so that herbicides are used to remove non-native plants naturalized to the Canyon, and non-native trees are cut down, to be replaced (if at all) with “native” shrubs and other smaller plants. Though the original Environmental Impact Report for the Glen Canyon project said it would not be in the Natural Areas of the canyon, in fact the work area did include a substantial “Natural Areas” portion.


Who, she wanted to know, did we target our video at, and what result did we wish to see?

Our video is intended to get the word out to people who care. San Francisco Recreation and Parks Department policy is hostile to the 117,000 non-native trees in the park system’s Natural Areas. (They are on the wrong side of the climate change issue). We hope this video will show our concerns about tree removals, trail closures and herbicide usage, and show that native plant gardens provide very limited recreation opportunities and are not sustainable.

Most people don’t understand what’s happening in their parks until they see trees being removed or pesticide notices or trails being blocked, and then it’s usually too late. They also can’t understand why a program like NAP is funded at around $1.5 mn annually (which would go up by a factor of 4 or more if the Significant Natural Resource Areas Management Plan is adopted), while recreation centers are closed because the Director was fired, or the retiring gardener in their local park was not replaced, or park patrols are infrequent because of staffing issues.

Here’s what we would like to see happen:

  • We would like trees to be preserved as far as possible unless they are truly hazardous (and it’s not used as an excuse). They should be the responsibility of a department that wants to protect them instead of one which wants them gone. San Francisco’s tree canopy at 13.7% is low compared to most major cities – and we lose more trees each year than we plant. Trees fight pollution and save lives. In this era of global warming, trees are a crucial resource, sequestering carbon. (Eucalyptus, a fast-growing and long-lived tree with dense wood, is particularly effective at doing this.) We want tree-felling for native plant “restoration” to be stopped and prevented.
  • We want to stop use of toxic herbicides in Natural Areas (all Tier I and Tier II herbicides).
  • We want no additional access restrictions on people or pets in Natural Areas.
  • We want financial resources to be allocated in line with people’s actual priorities – which would include functioning (and open!) restrooms, funding for recreational programs people enjoy, patrols that improve safety, trash removal.


Have we encountered different sub-groups within the native plants community, she asked, or did we really think there was one unified agenda?

Let’s be clear: We don’t object to native plants, or to the people who value them. When we speak of the “nativist agenda” we mean the ideological preference for native plants that drives such entities as the Natural Areas Program (NAP) to try to destroy existing trees, habitats, and recreation opportunities – and use powerful herbicides in natural areas. They are a small minority of our park users, and large areas of our parks shouldn’t be landscaped to their preferences, ripping out of plants that the rest of us enjoy and that are important to birds and other wildlife. (NAP has 1100 acres, about 1/4 of the total SFRPD land.) “Nature” does not favor one plant over another.

We have people from the “native plant community” among our supporters: they like native plants, but not the destruction of existing trees, wildlife habitats, and access opportunities.


Finally, she wanted to know who the San Francisco Forest Alliance was. Were we homeowners? Off-leash dog-walkers? Opposers of pesticides? (In the article – which we link below- she quoted Jake Sigg’s definition of us: “Forest lovers, feral cat activists, and off-leash dog walkers.”)

So who are we, really? We’re very broad group with one thing in common: People who enjoy nature and our parks and advocate for trees, the environment and for wildlife.  SF Forest Alliance is not a membership organization, so we don’t have a roster or dues. We’re a grass-roots organization with many supporters, some of whom are active in helping us to spread the word. Our petition to Mayor Lee is currently at over 1500 signatures – and this is only the latest of several of our petitions that got thousands of signatures (including many on paper only). If you want a better sense of who we are, read some of the comments on that petition – or on the earlier one HERE.

We have hikers, birders, and people who want public money spent on making parks more beautiful and accessible for recreation. We have homeowners, renters, and people who share apartments. Some of us have pets and walk them on- or off-leash; others don’t.  Some are parents or grandparents, others not.

We all want unrestricted access to our parks, for us and for our families (including children and pets) for active – not just passive recreation. We’re all opposed to toxic herbicide use in “natural” areas. We all oppose removing of healthy trees. We believe most people have these values.

The SFWeekly article said in conclusion: “So it’s not enough to be a tree-hugger anymore; you have to hug the right tree.”

For our part, we think all trees that aren’t actually hazardous are “the right tree” wherever they originated. Perhaps she referred to the Native Plants Community, who dislike non-native trees (and nearly all the trees in San Francisco are non-native, because it had hardly any trees before.)


The San Francisco Forest Alliance

If you’d like to read Rachel Swan’s article in the SF Weekly, it’s here: Going Native: A Plant Lovers’ War Turns Political