UCSF Plans More Damage to Sutro Forest

The main destruction of Sutro Forest – from the so-called “Vegetation Management Plan” of 2018 – is already underway. But a recent Draft Environmental Impact Report (Read it here: UCSF-CPHP-Draft-EIR (1) ) developed because UCSF is making significant changes to its 2014 Long Range Development Plan, presages even further damage.


The Aldea Student Housing, which is adjacent to Sutro Forest, was formerly subject to a “space ceiling” that limited construction there. Now it has been removed from the space ceiling, and UCSF plans to build dormitories up to 96 feet high in a 40-foot zone. This will involve demolishing the old buildings and putting the new ones on the same footprint – or possibly changing it all to a “completely reconfigured and redesigned site.” Either way, this is likely to destroy even more trees than the already painful Plan.

The pictures UCSF is using to mock-up the changes are already obsolete.

Almost all the trees along Clarendon Avenue and the corner of Christopher and Clarendon are gone. Trees along Christopher are likely to be felled as well. Essentially, the picture above can be visualized as bare of trees.


In addition, UCSF is removing an area at the bottom of Medical Center Way from the forest, and removing the trees from the area. (This is near Edgewood – the purple triangle with the diagonal black bars.) In “compensation” it will add back to the Open Space Reserve an area that is already part of the Reserve. (The green space with the diagonal bars, lying between the Woods parking lot and the Surge parking lot.)

In fact, in UCSF’s prior maps of Mount Sutro Reserve, that area is shown as part of the Reserve. (Something like this has happened before. An acre was taken for the Regenerative Medicine Building – and the offered compensation didn’t happen.)

Here’s a UCSF map from 2013 that shows the area as a green part of the Open Space Reserve.

UCSF will also be felling more trees as it replaces storage tanks within the foot print of the forest.

Finally, as icing on the cake – a grove of redwood trees on Parnassus are to be felled.


As the world – and California – faces climate change, carbon-sequestering trees are one of the few “easy” ways to help fight this. Not cutting down mature trees that store – and sequester – the most carbon is the first step. In addition, the Vegetation Plan for removing thousands of trees has a potential for disaster, as what was one a damp self-sustaining forest for over 130 years dries out and weakens.

San Francisco has a 13.7% tree canopy cover, the lowest of any major city in the US. That number is from 2013, and is probably smaller by now, as a lot of tree-felling is under way.

Posted in deforestation | Tagged , , , , ,

Trees on Clarendon Avenue Felled

Sutro Forest extended along Christopher to Clarendon Avenue.
The section at Christopher and Clarendon was decimated for the rebuilding of the pump station in 2009, possibly poisoned in 2013… and in 2019, it’s been clear-cut. It’s gone.


In 2009, the forest area on the corner of Christopher and Clarendon was a lush dense grove before the pumphouse was built in 2009 (as shown in the poster visualizing the pump station):

Pump Station on poster

In 2013, here’s what it looked like. At the time, there was concern that someone was poisoning some of these trees.  After that, the poisoned trees and a couple of others were removed.

In 2019, the entire grove was clear-cut. There’s no grove between Clarendon and the pumphouse, just a couple of trees left.

All that is left of these beautiful 125-year-old trees are stumps.

Meanwhile, the planned trailhead from Clarendon is being built. It’s going to look *very* different from the charming visualization presented by UCSF.



Also gone – the tall trees that lined Clarendon Avenue in front of the Aldea San Miguel UCSF student housing.

I remember a time when you couldn’t even see the fence from the street. When UCSF thinned the vegetation there many years ago, they promised plantings that would conceal the chain link fence. Well, they planted some vines, but the concealment didn’t happen.

The chain-link fence is more prominent than ever.

And across the road, a swath of trees adjacent to the homes on Clarendon have been felled too, probably by SF Rec and Parks (or possibly Sutro Tower, not sure).

The destruction  of Sutro Forest – and indeed, many of the ancient trees of San Francisco – continues. It’s probably not a coincidence that nearly all the trees felled are eucalyptus.

Note: This article is based (with permission) on a version published on ForestKnolls.info 

Posted in deforestation, Environment, UCSF | Tagged , , ,

Season’s Greetings, and Good Wishes for 2020

When we started this website back in 2009, we had no idea that we would still be running it in 2020! But so it seems, and the battle continues though it is an uphill one.

The forest has already been considerably thinned, and some areas effectively clear cut (notably the East Ridge Trail, above the Aldea Student Housing). The picture below shows what was formerly a dense forest, which was then felled. The eucalyptus is resprouting, but we expect the sprouts will be destroyed too.

Nevertheless, there are still beautiful areas in the forest, and still a lot to enjoy – especially if you do not compare it with what used to be.

The forest is resilient. We hope that the forest managers will eventually leave it alone, and as it has done for the last century, it will rebound into its own.

Meanwhile, we light a candle to the future. A green one, because trees are our last best hope for stemming the climate crisis.





Posted in deforestation, Environment, Mt Sutro Cloud Forest

Clear-cuts in Sutro Forest

At the end of March, we went into Mount Sutro Forest. We found a lot of trees had been cut down, and it’s practically a clear-cut on the East side – contiguous with the Aldea Student Housing, where housing density is planned to be increased.

There are a huge number of felled trees, and what was once a dense forest from which you could hardly see any buildings looks like a logging site. It’s evident from the photographs how this is drying out the forest – despite the very wet winter.

Other parts of the forest are not as bad, but it may be a matter of time. A lot of trees have been felled along the new trail from Clarendon Avenue, and there are bare patches with no canopy at all.


The sense of seclusion – the sense of stepping out of the city into a different, magical, world – is gone in much of the forest because of tree-felling and the removal of the understory. You can see cars and houses where before there was just forest.

Tree stumps are everywhere.


There are some areas that have avoided or recovered from the destruction of the trees and understory.

Still given the plans for Sutro Forest, we have no way of knowing for how long. Certainly, in less than a year, it already is very different. Within five years, we expect the footprint of the forest to be significantly smaller, the understory to be destroyed, thousands of trees to be gone. Here’s our assessment of the expected impact of the Plan: What will Sutro Forest Look Like after the Plan?

For those who have loved this forest, we have hundreds of photographs from nine and ten years ago, memorializing the beauty and habitat that was here.  A few of them are in our Photos section, many more are in the articles describing our rambles through the forest. The Contents 2009-2017 page links these articles by year and month.

Perhaps, in a way, it’s a metaphor for our planet.

Posted in deforestation, UCSF | Tagged , , , , | 1 Comment

Dead trees: the life of the forest

UCSF is undertaking an assault on Sutro Forest, starting with trees it classifies as “dead or dying.” We question whether the so-called “dying” trees are actually dying, or merely in a defensive mode against four dry years, from which they would have recovered after this wet winter had they been given the chance. And importantly, the dead trees have enormous value in the forest.

We republish this article by Jack Gescheidt, first published at TreeSpiritProject.com with permission and minor changes. (The article and all the images are copyright to Jack Gescheidt.)


Even tree lovers may not know the myriad ways trees some label “dying” or “sick” or “infected” or “infested” (with beetles or other insects) are in fact beneficial to a forest. Perhaps you’ve figured this out already, or know it intuitively, but forests do just fine without us humans interfering. Especially when our “helping” is driven by financial gain.

But fans of forest beware: timber companies hellbent on extracting more wood from U.S. and world forests have concocted yet another way of saying down is up, wrong is right, and denuding forests does a forest good. Their newest sell-off-the-forest pitch is to “remove” only “dead” or “dying” trees, to “clean up” or “manage” forests more “responsibly” implying this does no harm. Don’t believe it. All the quotations are used to indicate these terms are euphemisms which don’t convey the reality of how damage is done in “responsibly” “managing” a forest. This would actually entail leaving it alone, and certainly not bringing in heavy machinery.

Extracting “dead” or “down” or “dying” trees is only the latest insidious way of doing additional harm while ignoring the reality of our current situation: global warming is threatening humanity, which is caused in large part by decades of massive, and ongoing deforestation, nationally and globally. What we humans should instead be doing is leaving existing forests be, especially old-growth forests, not inflicting more damage or extractions of any kind. And planting more trees than we cut down — I mean, “harvest.” Important note: planting a sapling is NOT an equivalent replacement for cutting down a mature tree. Leave mature trees stand AND plant more trees. This would benefit us humans — as well as animals and plants and planet, because we’re actually all in this together. Deforestation for short term profit equals environmental and societal catastrophe in the long term.

The timber industry’s latest assaults begin ideologically. If they win over your mind, and public opinion, they will destroy our forests, and harm all of us in the end. In the public relations assault you’ll hear and read this lie: that forests benefit from industrial removal of “dead” or “dying” trees; that doing so has little or no impact on a forest’s health. Nothing could be further from the truth. Standing dead trees, and trees that have fallen over, and trees in any and every state of decay, are essential to the life cycles of decay and regeneration of a forest. And thus our health depends upon these, since we depend upon forests for carbon sequestration, oxygen production, soil creation, water filtration, wildlife habitat, and so much more.

Chad Hanson, Director of the John Muir Project, UC Davis researcher, and Sierra Club board member, says this about dead trees and forests:

We are trapped by an outdated cultural idea that a healthy forest is one with nothing but green trees. An ecologically healthy forest has dead trees, broken tops, and down logs. Such forests may not look tidy from the perception of a forester, but it (a forest with lots of dead trees) is the most biologically diverse and healthy, from a forest ecosystem perspective….Pound for pound, ton for ton, there is probably no more important habitat element in western conifer forests than large snags and large down logs.

The old practice of killing trees — what modern industry euphemistically calls “harvesting” — to make too many products that are either unnecessary or readily replaced with non-tree sources, has now become a suicidal practice. By killing trees and destroying forests everywhere, we are also killing ourselves, slowly, surely, and increasingly not so slowly.
Beware, too, other misleading, non-scientific labels like “invasive” and “non-native” which are also now commonly used to justify killing trees, plants, and animals, sometimes even by well-intentioned but tragically misled environmentalists. All have drunk the industrial agricultural public relations Kool-Aid. Meaning they kill wild plants and animals, imagining they are doing good, even justifying toxic herbicide use to do so.

READ MORE: http://www.TreeSpiritProject.com/Invasion Biology

Beware, too, other misleading, non-scientific labels like “invasive” and “non-native” which are also now commonly used to justify killing trees, plants, and animals, sometimes even by well-intentioned but tragically misled environmentalists.  All have drunk the industrial agricultural public relations Kool-Aid. Meaning they kill wild plants and animals, imagining they are doing good, even justifying toxic herbicide use to do so. READ MORE: http://www.TreeSpiritProject.com/Invasion Biology

Dead and decaying trees are precious to a forest. Here’s a short list of services they perform:

DEAD TREES are wildlife habitat — homes! — for many species of insects, birds and mammals including beetles, bees, wasps, ants, mice, squirrels, salamanders, shrews, bats, rats, and wildcats (lynx, bobcat), raccoons, martens, and even cover for larger mammals including mountain lions and bears.

Forest cafeteria…

DEAD TREES feed numerous fungi like mushrooms which in turn feed myriad animals, including rodents like voles.
DEAD TREES provide crucial habitat (nesting, roosting and food storage) for many species of woodpeckers that rely solely upon them. Woodpeckers require dead wood that’s easier to penetrate than living wood. So woodpecker habitat is destroyed when timber companies extract dead trees, and forest health suffers as woodpecker services are diminished.
DEAD TREES are food for insects which in turn feed larger animals including birds and mammals, all essential to forest health.
DEAD TREES create new soil, a critical component from which all life springs
DEAD TREES retain critical moisture in a forest as decomposing woody material

We must protect all remaining un-logged, or old-growth (over 200 years old) forests and leave intact any and all forests for their critical ecological service in our era of anthropogenic global warming. These include carbon sequestration (CO2 storage) as double duty; keeping the carbon in a living tree in its wood and out of the atmosphere, as well as allowing living trees to continue extracting additional CO2 from the atmosphere every day it is alive.

In addition to these obvious, rational-minded functions, now is also an ideal time for us planetary citizens to become more aware of the equally valuable emotional and spiritual tonic trees provide us. Notice and appreciate each individual tree growing near you, regardless of its species or its country of origin.

There are no “invasive” trees! You may have your favorites kinds of trees, but all provide critical ecological service. Maintain trees, care for them, plant more of them, and feel how they can reconnect us to the natural world we have for too long abandoned. If more of us do this more often, we just might be able to save our own species from dying too.

– Jack Gescheidt


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The Destruction Has Started in Sutro Forest

A short time ago, UCSF sent out a circular saying it was going to start the tree-felling in Sutro Forest. We were surprised, because they’re supposed to avoid doing this in the winter when the ground is unstable with rain, and in the spring and summer when it’s the bird-nesting season. Tree-felling season was supposed to be in the Fall. But no, it’s happening now and they intend to finish by March. Thousands of trees will be gone, and the forest as we know it will be severely depleted.

Well, it’s started. Recently, a forest-supporter sent us these pictures:

The email that accompanied the pictures was unhappy. “Not much of a canopy anymore. This sucks.”

“In that location there were also trees marked with red paint, presumably for future removal?” they said in a follow-up email regarding tree-cutting near Clarendon Avenue. “Feel free to use my photos on your site. It wasn’t very long ago when running or walking these trails transported you into a different almost magical world. Increasingly as more and more trees are cut down, the surrounding city intrudes. Thank you very much for your advocacy.


Tree cutting has started in the East Ridge area (above the UCSF student housing at Aldea), Clarendon area (parallel to Christopher Drive), the Woodland Canyon Area (below Medical Center Way), the Farnsworth area (between Edgewood Avenue and the UCSF campus).

These are, coincidentally, the areas of the forest that as long ago as 2009, UCSF had targeted for tree destruction. (This was back when they were seeking a FEMA grant to pay for it – which they withdrew when FEMA wanted evidence.)  The language of the memo presents this as removal of dead and dying trees, though we have concerns both about the definition of ‘dead and dying’ and about the habitat impact of so much tree removal. (And dead trees, are, in fact, a habitat treasure for wildlife.)

The memo says they plan to bring in goats to eat the understory in February 2019, but a subsequent memo says it’s happening earlier.

Anyway, what we can expect in Sutro Forest this year is a lot less forest – thousands of trees removed, missing canopy, and bare open patches where the understory is also gone.

We hope you have made memories of the beautiful forest as it used to be. This site has been fighting the battle since 2009; others started in 1999. Sadly, the Sutro Stewards, who partner with UCSF in working in this forest, support this felling of trees and destruction of the understory.

This 130-year-old forest is no longer going to be a forest. 




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Season’s Greetings!

Mount Sutro Cloud Forest

Photo credit: Paul Hudson

We’d like to bring you one of our favorite photographs of Sutro Forest, together with our best wishes to all our readers. Season’s Greetings to our forest lovers!

Posted in Mt Sutro Cloud Forest

Blackberry Provides Valuable Habitat

From time to time, over the years, we have written about the value of blackberry as habitat, and as part of this wonderful forest.  (See: Sutro Forest Ecosystem and Wildlife Habitat.)

Recently, wildlife photographer and observer Janet Kessler published this article on Coyote Yipps, documenting coyotes feeding on blackberry. It’s republished here with permission.


by Janet Kessler

[Click on the picture above for a 5-minute video of coyotes feeding on blackberry.]

Notice how gingerly the coyotes move around. That’s because thorns hurt them as much as they hurt us humans. Both coyotes carefully rummage through the patch of berries, picking just those that are perfectly ripe and delicious. They spent over half an hour doing so.

I’ve been noticing a lot of fruit seeds in coyote droppings everywhere lately, so coyotes all over are enjoying summer fruit. What I don’t know is if they are being drawn to the fruit simply because it is delicious and they like it, or if it is because their usual rodent pickings are scarcer at this time.

Please note that Himalayan Blackberries are an important food source, not just for coyotes, but for all sorts of wildlife, including birds, AND even we humans love to pick and eat them. They are a Horn-of-Plenty for so many species, not only as a food source, but also as an impenetrable, thorny thicket, which serves as a protective habitat barrier for wildlife from dogs and humans. It tends to be invasive, so it may need to be controlled in places, but let’s think twice about altogether exterminating such a useful plant.

Posted in Environment | Tagged , , ,

The Very Long Life of Eucalyptus Trees

From the time we established this website in 2009, we have battled a series of myths used to attack eucalyptus trees. One of the most pernicious is that the trees are short-lived, and so are dying of old age. We discovered that was not true, and dealt with it in our article, Eucalyptus Myths.

We are pleased to republish this very thorough article, which includes local examples of healthy eucalyptus trees over 150 years old. It is republished with permission and minor changes from Death of a Million Trees, a website that fights unnecessary tree killing in the San Francisco Bay Area.




When the native plant movement began in earnest, about 25 years ago, its proponents weren’t expecting blowback from those who value the existing landscape. As far as they were concerned, the trees had to be destroyed solely because they “don’t belong here.”

When they started destroying our predominantly non-native urban forest, they learned that it wasn’t going to be as easy as they thought. They began to defend their destructive projects with cover stories to convince the public who didn’t share their devotion to native plants that it is necessary to destroy non-native trees because they are a threat to public safety and to wildlife.

One by one, we have debunked the myths that were used to justify the destruction of our urban forest:

Great horned owl in eucalyptus. Courtesy urbanwildness.org

  • About 20 years ago, one of the first myths was that eucalyptus trees kill birds. It is an absurd claim that is completely unsupported by reality. With a lot of careful research, we were eventually successful in convincing the public that birds are not harmed by eucalyptus. In fact, many bird species are dependent upon the trees for safe nesting and winter nectar. That myth is dead.
  • The claim that eucalyptus and other non-native trees are more flammable than native trees was a powerful narrative that was more difficult to kill. As wildfires have increased in frequency and intensity in California, that claim is no longer credible because every wildfire occurs in native vegetation. Again, this myth was eventually disproved by reality.
  • More recently, we have finally put to rest the claim that “nothing grows under eucalyptus.” This myth was based on a theory that eucalyptus emits allelopathic chemicals that prevent the growth of plants in the eucalyptus forest. Thanks to a recent, rigorous study done at Cal Poly, we know with confidence that the allelopathy story is another myth.

It was not surprising that the nativists, having run out of bogus justifications, created a new narrative. In parks that the East Bay Regional Parks District had been planning to thin, we began to see clear cuts. When we inquired about why it was necessary to destroy ALL of the trees, we were told they were hazardous. Then, in the minutes of a meeting of East Bay Regional Park District Park Advisory Committee , we saw the claim that eucalyptus lives only 50-60 years. Simultaneously, this claim was made in San Francisco by proponents of destroying all eucalyptus trees there.

We eventually tracked down the source of that lifespan estimate to a website called SelecTree, which originally said that the longevity of blue gums is only 50-150 years. We knew that isn’t an accurate estimate because of how long blue gums live in Australia and how long they have already lived in California. We provided that information to the authors of SelecTree and were able to get the estimate corrected to “greater than 150 years.” That’s not nearly long enough, but it is the longest lifespan estimate available on that website and it corresponds with many other trees, including native Coast Live Oak.

In the process of researching the lifespan of eucalyptus, we learned several interesting stories about blue gums that have lived in California for 150 years and are still going strong. We would like to share some of this information with our readers today.


Blue gum eucalyptus and all other species of eucalyptus are native to Australia. They were brought to California shortly after the Gold Rush of 1849. Since they haven’t been in California 200 years, we don’t know how long they will live here. But how long they live in Australia is obviously relevant to answer that question because longevity is specific to tree species. We can expect some variation by climate, but not much, and the climate of Australia is similar to the climate in California with wet, mild winters and hot, dry summers.

We know that blue gums live in Australia about 200-400 years because Australian scientists tell us that:

Growth Habits of the Eucalypts by M.R. Jacobs, (Institute of Foresters of Australia, 1955, 1986): Blue Gum eucalyptus lives in Australia from 200-400 years, depending upon the climate.” In milder climates, such as San Francisco, the Blue Gum lives toward the longer end of this range.

That reference was corroborated by John Helms, Professor Emeritus of Forestry at UC Berkeley and an Australian who said in response to our question about blue gums in California, “Blue gums would commonly live for 200 – 400 years, although I presume that some might live longer.”

We also asked the Australian National Botanic Gardens. They said, “It’s possible that the average lifespan of a native species growing in the wild in Australia would differ to the average lifespan of the same species introduced in northern California, since introduced plants can often “escape” their natural predators when such introductions occur.”

In other words, since eucalyptus trees have more predators in Australia than they do in California, we should expect them to live longer here. This is called the “predator release” hypothesis. Ironically, that hypothesis is used by nativists to support their claim that eucalyptus is invasive in California. (California Invasive Plant Council rates the “invasiveness” of blue gum as “limited.) It’s only logical to apply that hypothesis to the question of how long blue gums will live in California.


However, using actual experience in Australia to predict the future of blue gums in California requires some speculation. Therefore, we turned to the question of how long they have lived in California for guidance. We found several interesting local stories about blue gums that were planted in California 150 years ago and remain healthy and vigorous today.

There are many examples of blue gums being planted as street trees in California about 150 years ago. One of the most well-known examples is the city of Burlingame on the San Francisco peninsula. When the City was founded in the 1870s, John McLaren was hired to plant trees to provide a much needed windbreak because the City was nearly treeless, as was the entire San Francisco peninsula. McLaren planted over 500 eucalyptus (blue gum and manna) along the main highway through Burlingame, along with a row of English elms. John McLaren was subsequently hired by the city of San Francisco, where he planted many more eucalypts while serving as superintendent of the parks department for 53 years.

The eucalypts in Burlingame are still thriving, but the elms have been dead for about 60 years. SelecTree says the longevity of English elms is “greater than 150 years,” the longest category of longevity published by SelecTree and completely open-ended.

El Camino Real bordered by Eucalyptus trees. Burlingame, SF Bay area, California, USA

The people of Burlingame greatly value their eucalypts and designated them as “heritage trees” in 1975 under a local ordinance. That local legal status did not protect them from several attempts by Caltrans to destroy the trees. The people of Burlingame came to the defense of the trees and were eventually successful in getting permanent legal status to protect 2.2 miles of the trees. That section of El Camino Real in Burlingame lined with eucalyptus was listed on the National Register of Historic Places in 2012.

Caltrans is now working cooperatively with the people of Burlingame to address safety concerns while “also keeping an eye to the prized grove of eucalyptus trees along the street.” A task force was formed in 2018 to discuss these issues. The City of Burlingame remains committed to the preservation of these trees, which suggests that they have a future there. (1)

The life span of street trees is generally much shorter than trees planted as forests because they are subjected to more wind and polluted air of heavily traveled roads, such as El Camino Real. Although blue gums have passed the test of those challenging conditions with flying colors, they have not been planted as street trees for decades. Their out-sized scale makes them unsuitable for that purpose. If blue gums can survive as street trees on heavily traveled roads, they can surely survive longer in the protection of their neighbors in forests.


The blue gums on the campus of Stanford University are another example of 150 year-old blue gums that are very much alive. Although blue gums were included in the campus landscape design of Frederick Law Olmsted in the 1880s, many of the blue gums actually predate his design: “Several hundred mighty giants on the campus date back prior to 1870 when Leland Stanford acquired several farm properties, one of which already had avenues of gum trees. They are mostly Tasmanian blue gums and red gums with a sprinkling of manna trees.”

Eucalyptus on Stanford campus

That description of the old blue gums was written in 1971. The trees are still alive and well. I worked on the Stanford campus for 10 years and walked among those trees at every opportunity.


Mountain View Cemetery in Oakland, California was designed by Frederick Law Olmsted in the 1860s. Like most of the East Bay, the site was treeless. Olmsted’s design was an eclectic collection of mostly non-native trees, including blue gums. The cemetery is on steep, windward facing hills, where the windbreak provided by blue gums is particularly valued.

Eucalyptus in Mountain View Cemetery, planted on an unirrigated windward facing hill. 2017

Olmsted designed a straight avenue through the cemetery lined with magnolia trees. Many of the magnolia trees have died and those that remain are in poor condition. SelecTree claims that the life span of Southern magnolia is “greater than 150 years,” which is contradicted by our local experience.

The current owner of the cemetery destroyed many of the blue gums about 5 years ago, in the middle of the extreme drought. He replaced many of the blue gums with redwoods. The redwoods are irrigated and are still surviving. I did not object to the removal of the blue gums because they are on private property. I confine my advocacy to healthy trees on public land.


SelecTree has revised its listing of blue gum longevity based on the information we provided. The myth that our blue gums are dying of old age will not die as easily. We will have to repeat this information many times and in many different venues, just as we did for every other myth. If and when that particular myth dies, we can be sure there will be another waiting in the wings. Ideologies stubbornly persist, despite contradictory evidence. And yet, we just as stubbornly persist in defense of our urban forest.

(1) Here is the public record, on which my report about the trees in Burlingame is based:







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UCSF to Start Cutting Trees in Fall 2018 – “Final EIR” Published

UCSF has issued its proposed Final Environmental Impact Report. (You can read it here as a PDF. It’s more than 2000 pages. Mount Sutro Vegetation Management Plan 2018 Final EIR_Full Document

They expect to have it certified by the Board of Regents soon. [Edited to add on May 5 2018: UCSF has announced the plan is approved. “Earlier this week, UCSF’s Chancellor approved the final plan following the certification of the Final Environmental Impact Report. Now that the plan is approved and finalized, UCSF can begin implementation in September, after the end of bird-nesting season.”]

This will mean they will start cutting down thousands of trees this Fall, probably in mid-August September 2018. If you love this forest, visit it now. It’s going to look very different by this time next year.


A lot of trees are already gone, cut down in the name of “safety.” This is true not only of the UCSF section of the forest, but also in the Interior Green Belt (the city-owned portion.)

It’s also going to be bad for carbon sequestration; a rough calculation made by the Nature Conservancy estimated that 1 acre of trees was equivalent to preventing a year’s emission by 30 cars. Cutting down trees here will release a lot of Green House gases.

We also expect poorer air quality. These trees fight particulate pollution, at least while they’re standing.

In both the short and long term, there may well be issues of slope stability. The trees, and their intergrafted roots, stabilize the slopes like a deep living geotextile. The trees also precipitate fog, keeping the surface soil damp, but use the moisture at the lower levels and thus prevent the soil from getting deeply saturated. As to roots of the felled trees die, the geotextile starts to decay. Meanwhile, the trees are no longer drying the deeper soil. The landslide risk could remain for years after the trees are felled, waiting for the right circumstances.

All the wiggly black lines in the map below indicate soil creep direction, and the straight double arrows show the direction of potential landslides.

Posted in Environment, Mt Sutro Cloud Forest, Mt Sutro landslide risk, UCSF | Tagged , , , , | 3 Comments

Two Nativist Myths: Eucalyptus Kills Other Plants; Mutually Exclusive Relationships are Common in Nature

We re-publish with permission (and added emphasis) an article from  MillionTrees.me, a website that fights the unnecessary felling of trees in the Bay Area. The article, a report from someone who attended the February 2018 meeting of the California Native Plant Society (CNPS), is important for two reasons:

  1. It has some notes from the presentation made by Dr Yost on the myth of eucalyptus allelopathy. (There is more information in this article on SFForest.org, the website of the San Francisco Forest Alliance: The Myth That Nothing Grows Under Eucalyptus.)
  2. It highlights one of the important myths of nativism: Mutually exclusive co-evolution.

One reason nativists believe it is important to “restore” native plants is that they believe that wildlife depends on these specific plants. If this was actually true, then destroying those plants would endanger wildlife higher up in the food chain, and potentially collapse the ecosystem. Doug Tallamy popularized this theory to non-scientists.

Do mutually exclusive relationships exist? Yes – but they’re rare. And they’re rare for a reason: They can’t handle change, and change is the norm for ecosystems. What’s much more normal in nature is adaptability – wildlife adapts to its environment, whether new food sources or new threats.  The result of change is often more diversity, not less.

The risk now is that a large number of people are invested in nativist theories – and practice, most of which involves chainsaws, pesticides, and digging up plants in a strange effort to garden the wilderness.

The abstracts from the CNPS conference are available here: CNPS 2018 technical-presentation-abstracts-by-session


I am pleased to publish the following report of one of our readers who attended the conference of the California Native Plant Society in Los Angeles at the beginning of February 2018. 

Million Trees

I attended the last conference of the California Native Plant Society in San Jose in January 2015.  It was interesting to note a few significant new themes in the recent conference in 2018.  Both fire and climate change were much more prominent themes in the recent conference.  While both are relevant to the future of native plants, neither seemed to have any effect on the “restoration” goals of the native plant movement.  For example, there were several presentations about massive die offs of native oak trees, resulting from higher temperatures, drought, and disease.  These presentations ended with urgent pleas to plant more oaks.  That seemed a fundamental contradiction and a denial of the reality of climate change.  When the climate changes, the landscape changes, but native plant advocates are not willing to acknowledge that.  In fact, the greater the threats to native plants, the greater the commitment to their preservation and “restoration.”


The conference began on a low point for me, but a high point for most attendees of the conference.  The keynote speaker was Doug Tallamy.  He was introduced as a “rock star” of the native plant movement, and indeed he is.  His presentation was very effective in delivering his message, which is that most insects are “specialists” with mutually exclusive relationships with native plants that evolved over “tens of thousands of years.”  If you believe that claim, you also believe that the absence of native plants will result in the absence of insects and ultimately the collapse of the entire food web.

Doug Tallamy’s closing photo, CNPS Conference 2018

Most native plant advocates believe that gloomy scenario, but few scientists still do, which creates a tension within this community of native plant advocates composed predominantly of amateur “botanists” and a smattering of academic ecologists.

For example, one of the first presentations after Tallamy’s keynote was an academic ecologist from UC Berkeley who advocated for accommodating the movement of plants outside of historical native ranges to accommodate climate change. (1) He said that restoring only with local natives is “maladaptive” and that a bioregional perspective is needed to create sustainable landscapes.  Allowing Monterey pines to grow in the San Francisco Bay Area, where they have grown in the past and are presently deemed “native” just 150 miles away, seems a good example of such a broader definition of “native.”  An amateur nativist, parroting Tallamy, asked this hostile question: “But if we move the plants how will wildlife survive?”  The academic delivered this tart dose of reality: “There are few mutually exclusive relationships in nature.  Wildlife will also move and will adapt to changes in vegetation.”

Science debunks a myth about eucalyptus

The high point of the conference for me was a presentation by Jennifer Yost, Assistant Professor at Cal Poly, San Luis Obispo.  She and her graduate student studied the claim that nothing grows under blue gum eucalyptus trees because of allelopathic chemicals emitted by eucalyptus that suppress the germination of other species of plants.  Two studies of this hypothesis were done in the 1960s, but the analytical methods used by those studies were misleading.

CNPS Conference 2018

Rigorous methods used by Yost’s team included planting seeds of 5 native plant species in the soil of eucalyptus forests and comparing germination rates of seeds planted in the soil of oak woodlands.  They also tested the effect of blue gum volatile leaf extracts, and water-soluble leaf extracts on germination and early seedling growth.

They concluded, “In these experiments, we found that germination and seedling growth of the species tested were not inhibited by chemical extracts of blue gum foliage, either at naturally-occurring or artificially concentrated levels.” (2)

CNPS Conference 2018

Yost observed that the lack of allelopathic effects of blue gum on the soil implies that blue gum forests theoretically can be successfully planted with native plants after removal of the trees.  However, she cautioned that those who destroy the blue gums should carefully consider what will replace them.  Will an aggressive non-native weed quickly colonize the bare ground?  If so, what is the benefit of destroying the blue gums? 

I had a conversation with one of the most influential nativists in the San Francisco Bay Area after Yost’s presentation.  This new scientific information does not alter his commitment to destroying blue gum eucalyptus in the Bay Area.  After all, there are many more negative claims that remain unchallenged by scientific studies.  For example, there are no studies that prove that blue gums use more water than native trees, as nativists claim.  Nor are there any studies that prove that eucalyptus leaves contain less moisture than the leaves of native oak or bay laurel trees, which theoretically makes eucalyptus more flammable, as nativists claim.  The lack of scientific evidence enables the persistence of speculation justifying irrational fear of blue gum eucalyptus.

Nativism dies hard because of lack of scientific studies

There appeared to be three distinct groups of people in the crowd of about 900 conferees.  There was a large contingent of grey-haired volunteers who are the backbone of every native plant “restoration.”  They are the dedicated weed pullers.  There is an equally large contingent of young people who are making their living writing the “restoration” plans and directing the activities of the volunteers.  The smallest contingent is a few academic scientists who study the underlying issues in their ivory tower.  The goals and conclusions of these three groups are increasingly divergent as scientific studies disprove the assumptions of the citizen “scientists.”

The tension between science and the citizenry is as evident within the native plant movement as it is in American politics at the present time. The general public rejects scientific evidence at its peril.  The rejection of science will not end well.  In the case of uninformed nativism in the natural world, the result will be a barren, poisoned landscape.

  1. “Climate change and open space conservation: Lessons from TBC3’s researcher-land manager partnerships in the San Francisco Bay Area,” David Ackerly1, Naia Morueta-Holme5, Sam Veloz3, Lisa Micheli2, Nicole Heller4 1University of California, Berkeley, Berkeley, CA, USA, 2Pepperwood, Santa Rosa, CA, USA, 3Point Blue Conservation Science, Petaluma, CA, USA, 4Peninsula Open Space Trust, Palo Alto, CA, USA, 5University of Copenhagen, Copenhagen, Denmark
  2. Abstracts of CNPS conference presentations are available here:  CNPS Conference abstracts
Posted in eucalyptus, nativism | Tagged , , ,

Bad News from Sutro Forest – Clearcuts in Interior Green Belt

A forest lover alerted us to some serious tree destruction on the Cole Valley side of Sutro Forest – the Interior Green Belt. This is the city-owned side of the forest.

We knew that some tree-cutting was planned. Some months ago, a storm blew a tree down onto a house at night, causing damage and putting the occupants at risk. (Fortunately, they were not harmed.) After that, we heard that 11 trees were removed along the forest edge.

What’s happening now is much more – some 40-90 trees. They are pushing the forest back along its Eastern edge. A lot of trees are already down, and some beautiful old ones have notices and orange dots showing they’re slated for destruction. This will happen within the next week.  [We understand from later correspondence that the number is 55 trees. That’s a lot of beautiful, mature trees.]

Again, “safety” is being used as an excuse for tree destruction well beyond the need to remove hazardous trees that threaten homes and buildings.

This forest, nestled in the heart of the city and surrounded by neighborhoods, is headed for destruction. First, the whole area will be shrunk for the purpose of creating a “defensible space” – even though that is probably the worst thing that could be done in terms of safety of a forest that garners moisture from the fog. Then tree cutting in the forest’s interior will increasingly dry it out.  And more trees will be cut down as wind-hardened trees from the forest edge are removed.

BACK IN 1958

This strip, the Interior Green Belt, was saved when the then-expansive forest was felled for development. It’s ironic that the trees preserved 60 years ago with so much difficulty are casually being cut down now. Here’s what the newscopy was back then:

Newscopy: “Once a quiet wilderness area, now Sutro Forest is becoming thoroughly developed.”

Newscopy: “This is the story of Sutro forest – and how the city has laid it waste. It is a story of trees versus concrete. Of green glades gobbled up for houses, eave-to-eave, row on row. Maybe it is the story of our way of life, inevitable in the push of population. But in many ways it is a tragedy. For Sutro Forest was once an 1100-acre spread of foliage within the vast Adolph Sutro-owned San Miguel ranch, and its trees were man-grown, hand-planted in a painstaking effort to provide beauty for San Francisco. But the march of the city is trampling the forest down, plucking it out by roots. Sutro was near as our sandy hills came to having ‘the forest primeval.’ But it’s now ‘the vanishing pine and hemlocks…’ Only a few people care. Some Twin Peaks home-owners have protested. Only one city agency – the Planning Commission – has sought to preserve at least leafy fragments, snatching an acre here, two acres there almost from the bulldozers. Now it is trying to salvage one parcel of 12.5 acres…”.


People saved it then; perhaps people can still save it from the forces nibbling away at its borders and heart.


Posted in Mt Sutro Cloud Forest, Natural areas Program | Tagged , , , , | 14 Comments

Season’s Greetings!

It’s the holiday season again, and we’d like to wish all our readers and supporters all the best, for this season and for the year ahead.

Painting by Brian Stewart

We’d like to celebrate with this quiet painting by artist Brian Stewart, showing bees on eucalyptus flowers.

As the world’s tallest flowering plant, and one that blooms year-round, eucalyptus gives sustenance to a host of creatures: Bees and other insects, birds that feed on the nectar or the insects, or nest in and on the tree. To us, this tree symbolizes the giving spirit of the season.


Posted in Environment, eucalyptus

Lest We Forget (2): Sutro Forest 2007

This website was set up only in 2009, and except for a few pictures of San Francisco in the old days, most of our photographs come from June 2009 or later. Hiker Tony Holiday (who blogs at Stairways are Heaven) shared with us some pictures from before that. These are from 2007; in an earlier post, we published pictures from 2004, 2005, and 2006 to recall the beauty and density of the forest before most of the “work” started and before most of the tree-felling started. We publish them here with permission.


These pictures, taken on a hike in 2007, show the lush green forest in the early days of the “work” when the main objective was opening the trails. This was something everyone could get behind.

The forest, green and lush in January as it was in May. The forest gets rain in winter, and cloud forest precipitation in summer. It’s green year-round.

The tank picture below shows the original trailhead for the upper Historic Trail. Later, they opened the trail right off the road as it is now.” – Tony Holiday

The forest is always green except where it’s opened up and dries out. The picture below shows the summit, which is the driest part of the mountain. Even in winter, the grasses quickly dry.

While Sutro Stewards and UCSF were mainly building trails, they got a lot of public support. But later, when they supported destroying trees and the forest’s ecology, forest-lovers realized the need to work to save this beautiful ecosystem.

Posted in Environment, Mt Sutro Cloud Forest | Tagged , , , , | 2 Comments

Lest We Forget: Sutro Forest – 2004, 2005, 2006

This website was set up only in 2009, and except for a few pictures of San Francisco in the old days, most of our photographs come from June 2009 or later.  Hiker Tony Holiday (who blogs at Stairways are Heaven) shared with us some pictures from before that – between 2004 and 2006. We publish them here with his permission, to recall the beauty and density of the forest before most of the “work” started and before most of the tree-felling started. (Later on, we’ll publish some 2007 pictures of the forest as well.)

[Edited to add: We did. Lest We Forget (2): Sutro Forest  2007]


This is Medical Center Way, a paved road that runs north-south through the forest and connects the Aldea Student Housing with the UCSF campus. The beautiful eucalyptus trees festooned with ivy come right up to its edge.


Here’s the summit garden in 2004, with flowers in bloom.

Here are more wildflowers, also from May 2004.

What a change from now – same place !” commented Tony. He’s right. The summit seldom manages to look like this any more. In the early days of the garden, an extensive irrigation system was installed. (You can see the pipe in the picture above.) They stopped irrigating it after 4 years, we’ve heard. This must have been while it was still being watered. For contrast, here’s a picture taken in May 2010.

And here’s yet another from 2004 – a lovely nasturtium understory under the eaves of the forest. (The nasturtiums need no watering.)


This is the trailhead from Crestmont, in the Forest Knolls neighborhood, in 2005.

Another view of the trailhead, showing the wooden steps and flowers planted beside them. A graceful entrance to the forest with trees standing sentinel on either side.

And here are two from Medical Center Way again, still looking like a woodland road under a tree canopy.


Here are some lovely Sutro Cloud Forest pictures from 2006.

The hiker half-hidden behind the tree gives a sense of scale and mystery. The picture below, taken in July 2006 shows how lush the forest used to be before the “thinning” started.

These rocks are the Fairy Gates that give the Fairy Gates Trail its name. (One of the originators of this trail, long before it was tidied up and reopened, objected to the name. He called it the Topo Trail.)

Here’s a view of the UCSF Chancellor’s Residence through the trees. With the forest at its back and a view over the city at the front, it must be one of the best houses in San Francisco.

Another pretty trail picture from 2006:

A view of the trailhead off Medical Center Way

And the steps leading down to the UCSF campus


Back when I went on these group hikes they were just opening the upper Historic and Mystery Trails to the public. The lower Historic had not been opened yet.” – Tony Holiday

Tony also sent us these pictures from a group hike:

Back then I took group hikes and was totally innocent re efforts planned to thin out the forest !!” – Tony Holiday

Thank you, Tony, for this time machine. It reminds us of what the forest could be again if they stop fighting resurgent nature.


Posted in Environment, Mt Sutro Cloud Forest | Tagged , , , , | 2 Comments

Furious Letter from a Forest Lover

We received this letter from a long-time hiker in Sutro Forest, who is aghast at the destruction there. We publish it unedited.


“Dear fellow environmentalists and friends of Mount Sutro Forest …

I am lately shocked and horrified even more than usual by the great harm being done to Mount Sutro.

The despicable monsters who are responsible for this ongoing destruction should be jailed/fined for crimes against the environment.

First of all, the trees at the Belgrave trailhead have been felled and huge logs lie across the ivy.

Sutro Cloud Forest - Belgrave Trailhead with felled trees - 2017

Sutro Cloud Forest – Belgrave Trailhead with felled trees – 2017

As you climb higher up, it fortunately (so far) looks as gorgeous as ever — but this was such a shock…

How could these misguided tree killers be allowed to continue to destroy Sutro Forest and other parks and green spaces?

Irreparable harm is being done to the upper Historic Trail also, as well as the other trails. Logs and branches were all over and huge trunks along the trails, some where sawdust was still on the trail next to the doomed tree. Of course it was unnaturally dry where these crazies have done their damage.

It would improve my mood greatly to see the demise of these destructive, antienvironment tree-haters.

What was supposed to be a peaceful nature appreciation hike turned out to also be a bummer as not only did I note with horror the destruction of beautiful, big, healthy trees, but all along the trails as well were the big green dots on other trees that were marked for murder by this bunch of environmental criminals.

It appears they would like nothing more than to make Mount Sutro as bare as Twin Peaks and Bernal Heights Park.


We’re saddened  that two entrances to the forest that were absolutely magical are now … ordinary. The entrance at Belgrave was a couple of posts leading to a narrow winding trail amid tall trees. Once you stepped inside, it was another world.

Sutro Cloud Forest - San Francisco CA - Belgrave Trailhead 2006

Sutro Cloud Forest – Belgrave Trailhead 2006

The entrance to the Stanyan trail was similar – a sudden, miraculous transition from an pleasant residential area into a fairy-tale forest in the heart of the city. Those entrance trees are also gone, victims of “tree-work” after the Stanyan trail was opened up.



Posted in deforestation, Mt Sutro Cloud Forest | Tagged , , , | 5 Comments

“Hazardous Tree Work” – Cutting Down Trees on Mount Sutro This Winter

Well, the nesting season is over – and the cutting is starting.

On Nov 9, 2017  we received a notice from UCSF that they are starting “hazardous tree work” on Monday November 13. 2017.  They plan on cutting down 50 trees and pruning about 200.  Since “hazard” is a popular excuse when people want to cut down trees, we asked for documentation that the trees are actually hazardous.

We won’t get it before work starts – Friday Nov 10, 2017 UCSF was closed for Veteran’s Day, then it’s the weekend, and then work starts Monday Nov 13. However, it is going to continue intermittently through January 2018, so we will update you when we know more. The UCSF notice is below:

UCSF’s NOTICE – NOV 9, 2017

Here’s the notice:


UCSF Hazardous Tree Work

Dear Neighbors:
UCSF is scheduling hazardous tree trimming and removal starting Monday, November 13. The work will occur along the Historic, Northridge, Clarendon, Fairy Gate, and potentially East Ridge trails. We estimate that approximately 50 trees will be removed, and 200 trees will be pruned.

The work is expected to occur intermittently through January, 2018. The work will be done using chainsaws and hand tools, which will generate noise in the area. UCSF’s good neighbor commitment limits noisy work on weekdays to between 8 a.m. and 5 p.m. During the work, the affected trails will be closed, and visitors will be redirected. Signs will indicate where trail closures will occur.

If you have questions or concerns, please contact Lily Wong at (415) 476-8318 or email at Lily.Wong3@ucsf.edu.


We are pleased that they are actually pruning trees instead of cutting them all down. But we suspect that the tree-cutting activity planned by UCSF is more aggressive than safety demands. They have not been good at identifying hazardous trees. A recent tree-fall in the Aldea campus was from a tree that was considered safe, according to Julie Sutton, (UCSF’s arborist managing this forest). Meanwhile, over a thousand trees have been cut down over the last few years.

UCSF needs to be more aware of the risks of thinning the forest and destroying its capacity to hold moisture. This impacts many safety issues, including slope stabilization, forest health, and windthrow.

Posted in Environment, Mt Sutro Cloud Forest, UCSF | Tagged , , , ,

Barn Owl in Sutro Forest

Evening visitors to the Sutro Forest have long known that Great Horned Owls live or visit there.  They’re specially easy to hear, with soft resonant hoots.

Dusk, mist, Great Horned Owl

Last night, it was a Barn Owl, which is less easy to see. This account is republished with permission  from ForestKnolls.info, a website/ blog for the neighborhood just south of Sutro Forest.


I was driving west along Clarendon Avenue, heading homeward. As I slid into the turn lane to make a right on Christopher, something white lay on the side of the road. I slowed nearly to a stop, unsure what it was. Then I recognized it as a barn owl, wings spread. My fear was that it might be injured, perhaps from hitting a car.

To my relief, it rose into the air and disappeared into the trees of Sutro Forest, a rodent clutched in the talons of its right foot. It must have just caught it. I breathed a sigh of relief.

But I was in even more luck! As I turned right, it sailed out of the forest ahead of me, looped over Christopher Dr, and flew back to a tree beside the street. Then it took off again, but only went a little deeper into the forest.

The last time I saw a barn owl in Forest Knolls was seven years ago: Evening Walk with Owl and Moon

Later, I went back. The owl was there, but difficult to see in the darkness. I heard rustling sounds that suggested it was eating the rodent it had caught. I tried getting photographs, but both my phone and camera rebelled at the darkness. This picture is an edited public domain photograph.

So if you hear hisses, screeches, and rasping noises from the forest – or around our neighborhood – it’s barn owls on rodent patrol. (Also, please don’t use rodenticides, especially slow-acting ones like brodifacoum. It could kill the owl.)

Posted in Environment | Tagged ,

Monarch Butterfly at Twin Peaks – Oct 2017

A few days ago, a viewer watching the planes rehearse for Fleet Week spotted a different kind of aerial phenomenon: Monarch butterflies, fluttering around over Twin Peaks.

“I was driving by Twin Peaks,” they wrote, “and paused to watch the stunt airplanes… and I saw several Monarch butterflies. I had a hard time getting a photo, but here’s a blurry one.” They ended with a plea to photographers armed with something more than an iPhone:  “Someone, please get some better shots?

Will these butterflies overwinter in the eucalyptus forests on Mount Sutro and Mount Davidson? They may very well do so. It’s excellent habitat. We’re reprising below part of an article written after a visit to Natural Bridges State Park, where these insects regularly roost.

This is particularly crucial in view of UCSF’s plans to cut down thousands of trees on Mount Sutro – according to the 2017 Draft Environmental Impact Report, as many as 4,500 trees in the first year alone, and 6,000 in Phase I (the first five years).

Excerpts from


We’d read that Monarchs might feed from eucalyptus flowers, which provide a winter resource to so much wildlife. That proved to be true. Looking through binoculars, we saw the eucalyptus flowers far overhead were full of butterflies.

We knew, of course, that Monarchs depend on eucalyptus trees along the West Coast. What we also learned was that other so-called “invasive” plants also help Monarch butterflies to survive. The boardwalk trail has interpretive signs with infographics. We found this one, Nourishing Nectar, particularly interesting.

nourishing nectar sign about Monarch butterfliesEnglish ivy is one of the key plant species of Sutro Forest – and it’s under attack in both the old and new Plan for Sutro Forest. Since the Monarch butterflies found its nectar a nourishing snack, surely this would also be true of other nectar-feeders. Are UCSF – and the Sutro Stewards who do much of the actual work – aware of the habitat destruction killing this ivy causes?

cape ivy

Cape Ivy provides cover and habitat

We didn’t see English ivy in bloom at Natural Bridges State Park this December. Maybe as a fall-flowering plant, its season was over. But Cape Ivy around the tree trunks had small yellow flowers that offered the Monarch butterflies another snack.

monarch butterfly nectaring on Cape Ivy 2

Monarch Butterfly nectaring on Cape Ivy Flower

Cape Ivy is also one of the plants in the understory of Sutro Forest, and it’s being targeted for destruction along with English ivy. Yet its nectar clearly has nutritional value for insects and thus, it has a place in the food chain. And it’s obviously important as habitat and cover for small birds.


We were interested to learn that, unlike the Monarchs east of the Rockies (which migrate from Canada to Mexico and back), the butterflies in the West migrate between the interior and the coast.  The butterflies east of the Rocky Mountains go south to Mexico in winter. The butterflies on the Western side come to the California coast.

fallmigrationmap usfwsThe Monarchs in the Western migration depend heavily on non-native, naturalized species of plants. Some 75% of the Monarch roosts are mainly eucalyptus. In fact, eucalyptus, Monterey Pine, and Monterey Cypress (which nativists consider an “non-native” species outside the Monterey Peninsula) account for around 90% of the tree species they use.

But as we saw, they also draw sustenance from Fall and Winter-blooming ‘weeds’ like English ivy and Cape ivy. This can be critical – the Fall generation of these butterflies is the longest-lived, and makes the migration to the Coast and back again that preserves the species. The extra nutrition improves their likelihood of surviving.

Western migration explanation

Of course, it’s not just naturalized plants. Milkweed is the Monarch’s nursery plant; that’s where it lays its eggs and where its larvae feed. The main threat to the Eastern migration – which has been declining sharply – is that farmers use more pesticides than ever to eradicate weeds, and the butterflies are simply not finding enough of it. There’s a move to grow more milkweed.

Meanwhile, it’s crucial to preserve the Western migration, which seems robust for now. What would happen if the eucalyptus that shelters these butterflies are felled?

[Edited to Add: Apparently it’s NOT robust. See the comments.]

It could happen. We don’t think that anyone would cut down trees that are well-known as Monarch roosts – as in Natural Bridges State Beach. But in some years, the butterflies spill out into other trees, and could potentially establish new overwintering sites. Two years ago, they even came to San Francisco.


The whole area we visited was a lively habitat of naturalized plants. Eucalyptus. Ivy. Blackberry. Grasses. It was full of wildlife, and not just butterflies. We saw a lot of birds, and heard the rustles and twitters of even more. A Townsend’s warbler made a brief appearance before diving back into cover. And high above, we heard a woodpecker – maybe a Downy – in a eucalyptus tree.

woodpecker tree

maybe downy woodpecker

Downy Woodpecker?

Native plant advocates say that native plants provide superior habitat for native species of animal life. There’s no evidence that this is true. Some few species of insects are tied to particular plants, but even then, the rapid reproduction rates of insects suggests that they would evolve to use new plant species once they’re plentiful enough. A great example: How the soapberry bug adapted to use a new food source – in only 100 generations (about 20-50 years).

All the evidence is that naturalized plants provide a resilient and rich habitat for a range of animal species – and with no extra effort from land managers. We only have to avoid destroying them.


Posted in Environment, eucalyptus, UCSF | Tagged , , | 2 Comments

Disturbing Sutro Forest Would Release a Lot of Green House Gases

We’ve pointed out before that Sutro Forest is an excellent carbon sink: The trees are tall, fast growing and have dense wood. In some parts of the forest, the mid-story of blackwood acacia boosts this carbon storage as well. The understory is lush and evergreen. The forest floor is damp most of the time. It’s practically the perfect carbon forest. It’s also a special ecosystem and excellent wildlife  habitat.

Disturbing this forest is going to release Green House Gases (GHG), and the Sutro Forest DEIR (where the deadline for comments closed on September 22nd) underestimates how much. Here, we publish with permission the comment from Eric Brooks. He’s the Sustainability Chair, San Francisco Green Party and Campaign Coordinator, Our City SF. [Please note: all the photographs in this article are ours and not part of the comment sent to UCSF.]


Comments To: Draft Environmental Impact Report (Draft EIR) – UCSF Mount Sutro Open Space Reserve Vegetation Management Plan

Fundamental GHG Calculation Flaws & Neglect of Wildlife Habitat Retention Strategy

To all concerned with the Draft Environmental Impact Report for the UCSF Mount Sutro Open Space Reserve Vegetation Management Plan,

I write to raise very serious concerns about very fundamental and deep flaws in the Draft EIR (DEIR) assessment of greenhouse gas emissions from the proposed project and related wildlife habitat impacts.

The assessment has key and deep flaws in its methodology for greenhouse gas assessment, and must be fundamentally changed, and the assessment completely redone.

1) The first deep flaw in the methodology and assessment is the assumption on page 4.7-3 that:

“Forest‐soil carbon is a large, stable pool, accounting for some 50 percent of the total forest carbon and changing very slowly over hundreds of years (Kimmins 1997). For timeframes of 100 years and less, forest accounting can ignore this pool and focus on changes to more labile forest carbon components (i.e., trees, understory, litter).”

This assumption is simply not correct and completely ignores the fact that when forest soils become both disturbed and more exposed to the elements, due to tree and vegetation removal, vast amounts of carbon in the form of CO2 and methane are released *from* the soil. The greenhouse gas emissions calculations and assessment must therefore be completely redone to include soil carbon losses in the calculations.

2) The second deep fundamental flaw in the DIER greenhouse gas assessment is its reliance on the Significance Criteria under section 4.7.5 on page 4.7-10

This criteria is solely an arbitrary emissions cap and is the wrong criteria. The only proper criteria by which to assess greenhouse gas emissions of a forest is to compare its net carbon sequestration and emissions before disturbance, to its net sequestration and emissions after disturbance, in order to make a comprehensive assessment of its full internal net sequestration and emissions impacts – including all soil impacts and carbon losses and sequestration. It is the percentage net increase of greenhouse gas emissions in any given forest that matter, not an arbitrary cap on a specific emissions number which is not related to the full carbon cycle of that specific forest.

Therefore this assessment must be fully redone to examine solely the correct net sequestration and emissions, from the forest area that will be managed, accounting for all factors, and also accounting for the fact that near term net emissions over the next 20 years are the most significant because it is over the next 20 years that the planet is hitting a wide array of extremely dangerous climate crisis tipping points, and also because that is the proper window in which to analyze the forcing effect of methane (about 87 times higher than CO2 under that time frame).

3) Besides, and partly because of, the completely incorrect omission of soil carbon loss in the assessment, the net sequestration/emissions calculations in section 4.7 are far too optimistic and appear to be incorrect. This section does not properly and fully account for all emissions and sequestration losses, with an eye to new data which shows that after forests are disturbed it takes at least a century, and likely longer, for a disturbed forest to return to net sequestration of carbon. See links below which discuss these dynamics and which can serve as a starting point for redesigning and redoing your greenhouse gas analysis to make it an accurate one.

4) Chipping of felled and downed trees induces them to lose their carbon to the atmosphere much more rapidly. This assessment must be redone to show options for not chipping felled and downed trees at all, and instead leaving these trees intact, and on site, both as snags and downed trees. (See point 5.)

Chipping in Sutro Forest – 2016

5) Removing any vegetation (especially trees, including dead and felled trees) from a forest, drastically reduces the ecological capacity of that forest to uptake, store and retain carbon, and also dramatically reduces the crucial role of intact dead and dying trees to serve as wildlife habitat.

This DEIR contains no management assessment or mitigation plans that would call for a dramatic reduction in tree felling and removals in order to leave the forest and its soils as undisturbed as possible in order to maximize carbon sequestration, and maximize wildlife density and biodiversity through enhanced intact habitat. See the third link below to the report “The Myth of Catastrophic Wildfire” by expert forest ecologist Chad Hanson, PhD, to get a sense of, and some numbers on, the importance of leaving dead and dying trees intact and on site in a forest.

This assessment must be completely redone to show a management and mitigation option which *only* removes dead and dying trees *which pose a direct threat to human health and safety and property integrity* while leaving all other trees in the forest undisturbed. This assessment must include both net greenhouse gas, and wildlife density and diversity impacts.


Old-growth forests as global carbon sinks – Sebastiaan Luyssaert, et al
(contains extensive data showing that forests store more carbon the less they are disturbed)

Forest Carbon Basics – Mark E. Harmon, PhD (contains basic numbers for how forest and soil carbon dynamics operate over both short and long term timescales and shows clearly that disturbed forests store less carbon for a century or longer)

Click to access Forest_Carbon_Basics-Harmon.pdf

The Myth of Catastrophic Wildfire – Chad Hansen, PhD
(See pages 19, 22 and 23 *and* referenced documents and studies)

Click to access TheMythOfTheCatastrophicWildfireReport.pdf

Thanks for your attention to this extremely important matter.

Eric Brooks
Sustainability Chair, San Francisco Green Party
Campaign Coordinator, Our City SF

Sutro Forest

Sutro Forest viewed from Forest Knolls

Posted in Mt Sutro Cloud Forest, UCSF | Tagged , , ,

What Will Sutro Forest Look Like After the Plan?

It’s going to look pretty awful in Sutro Forest when UCSF implement the Plan.
The most immediate action: Cut down thousands of trees. Here’s what the Draft Environmental Impact Report (DEIR) says:

“The density of the forest would experience the most rapid decrease during Phase I of the plan. The largest number of trees and largest amount of vegetation would be removed during Phase I to manage forest treatments areas, defensible space, and native restoration areas.”

Phase I is what will start immediately after the Environmental Impact Report is certified, probably this Fall.

  • They will widen two of the major trails into roads suitable for heavy machinery.
  • They will clear NINE quarter-acre “staging areas” for machinery. (Bear in mind we’re speaking of a forest that is only 59 acres in total!)
  • They will remove a *lot* of trees, especially on the South Ridge.
  • They will shrink the total area of the forest by about a third.

The impact is going to be Significant and Unavoidable, according to the DEIR.

The “Aesthetics” section of the DEIR shows “before” and simulated “after” pictures of the forest from 5 strategically selected vantage points, or “Key Observation Points.” (The map showing where they are is at the end of this article.)


Only one of the Key Observation Points  is outside the forest, and for some quixotic reason, it’s taken from Midtown Terrace, from a location where there’s no clear view of the forest. There are no simulations of the look from the communities immediately surrounding the forest – Cole Valley, Forest Knolls, Inner Sunset, even though the DEIR notes that those neighbors are most aware of how the forest looks. There’s no simulation from the obvious viewpoint, Twin Peaks.

For the external view, they admit: “…the removal of trees would reduce forest density and create a gap near the south side of the Reserve…” but deny it’s significant. We were unable to replicate the picture that UCSF has in its DEIR.  But here they are. They show barely any change.

We doubt this is accurate, and we don’t think they’re considering the impact of all the other tree removals for the road, the staging areas, and the groups of trees they just want to cut down.

Here’s our picture of Sutro Forest from the South –  from Twin Peaks – before tree-felling.

Here’s our own  best guess simulation of what it will look like after they’ve hacked down many of the South Ridge trees. We’re using a basic Paint program, so it’s crude, but we think it gives a better idea. (This may even be optimistic.)

Or, when they eventually manage to destroy all the trees…

From the Cole Valley side, UCSF provides no simulation at all. Yet one of the major areas for tree removal lies just above Medical Center Way, the paved road that bifurcates the forest. Here’s the view from Tank Hill:

Here’s what would happen with removal of the large trees above Medical Center Way.

And then – if the trees gradually get removed, maybe it will return to this. (The second picture below is an actual photograph from before the trees were planted.)


The Aesthetics section argues that for hikers, the dead trees uglify the forest. We suspect that the authors of the study have no understanding of how a naturalized forest looks. It’s supposed to have trees in all conditions – they all have a part to play in the forest’s ecology.

They show four simulations from inside the forest, of dubious accuracy. The pictures show many trees gone, but they show a lot of understory remaining – even though the plan is to gut the understory.

The first picture looks like a forest. The second – well it’s a trail, with some trees around. And they show distant views, which in real life will only appear a few days each year – this is, after all, a Cloud Forest right inside the Fog Belt. Much of the year, it’s look like this.

If you love the mysterious, green, dense Cloud Forest on Mount Sutro, you should plan to make memories really soon. And get your comments to UCSF in.  If the Plan is implemented this year, as is planned, the forest you know will be gone in months.


They should be sent by email (EIR at planning.ucsf. edu) or mail to Ms
Diane Wong, at UCSF Campus Planning, 654 Minnesota Street, San Francisco,
CA 94143-0286. Phone 415-502-5952

Also write to:
1) Governor Jerry Brown, c/o State Capitol, Suite 1173, Sacramento, CA
95814. Phone 916-445-2841; Fax 916-558-3160
2) The UC Board of Regents. Address: Office of the Secretary and Chief of
Staff to the Regents, 1111 Franklin St, 12th Floor, Oakland, CA 94607
Fax (510) 987-9224. Their email address is regentsoffice@ucop.edu
3) Dr S. Hawgood, Chancellor, University of California, San Francisco
513 Parnassus Avenue S-126, San Francisco, CA 94143-0402, Phone 415-476-1000
Email Chancellor@ucsf.edu or sam.hawgood@ucsf.edu
4) Vice Chancellor Barbara French – Barbara.French@ucsf.edu
5) Copy to Supervisor Norman Yee – Norman.Yee@sfgov.org
6) If you could copy us at fk94131@yahoo.com that would be


Here’s the map of the Key Observation Points (including the only one from outside the forest – in Midtown Terrace).



Posted in deforestation, Mt Sutro Cloud Forest | Tagged , , ,

Sutro Forest Plan: Heavy Machinery in Unstable Areas

Recently, we wrote that the  Sutro Forest 2017 Plan Imposes a Landslide Risk. A University of Washington study shows that mudslides are most like 5-10 years after trees have been cut down on slopes. The picture below shows the South Ridge, which will be directly affected.

But it’s not just the tree-cutting. UCSF is widening two major trails into roads fit for heavy equipment, and adding nine quarter-acre “staging areas” for machines and felled trees. Both the roads are above Forest Knolls. (The heavy yellow lines in the map below are the new roads. The red squares are the locations of the staging areas, each of which will be a quarter acre.)

The picture at the top of this article gives some indication of how steep the hillside is. And the  roads above Forest Knolls are atop a slope *known* to be unstable. Look at this landslide hazard map:

The double black arrows show landslide direction. The wiggly black arrows show soil creep direction. All those dark green areas? Potentially unstable. All the gold areas? Also potentially unstable.

Though the Draft Environmental Impact Report claims it’s making safety its first priority – it doesn’t look like it. In attempting to mitigate one (overstated) concern (dead trees falling), they’re worsening the risk of landslides.


— ### —

Posted in Mt Sutro landslide risk, UCSF | Tagged , ,

Sutro Forest 2017 Plan Imposes a Landslide Risk

Landslide under blue tarp. South Ridge at top left.

We’re reading the Draft Environmental Impact Report (DEIR) for the 2017 Sutro Forest Plan, and got to the section on landslide risk. This has been one of our concerns, especially since the tragedy at Oso, Washington, where the felling of trees in previous years was a factor in destabilizing the slope. (We wrote about that HERE: Cut Trees, Add Landslide Risk) We know this area is subject to landslides – we had a blue tarp covering unstable areas in Forest Knolls for a year when cutting trees destabilized a slope, and another just above UCSF’s Aldea housing area.


We were shocked at what we found in the DEIR:
“Increased instability could cause a landslide that would impact Crestmont Drive, Christopher Drive, and Johnstone Drive. An existing landslide scarp is visible above Christopher Drive. Some homes along Christopher Drive could be placed at additional risk from localized landslides due to plan implementation. Phase I activities would result in a potentially significant impact…”

The map above is taken from the DEIR. All the dark green areas are potentially unstable. All the gold areas are potentially unstable. All the cream areas are potentially unstable. The little red blobs and stars are already unstable. The black arrows show the direction of potential landslides – right into our communities. Here’s the key to the map. The light yellow and light green areas are where they are cutting down trees in Phase I (five years, starting this fall – 2017):

Legend to Landslide Hazard Map Sutro Forest 2017

What’s the proposed “mitigation”? Avoiding work in the forest for 2 days when the soil is wet after rain. This completely ignores the fact that landslides are a MULTI-YEAR hazard after tree removal.

Here’s the proposed mitigation in their own words:
“After a significant storm event (defined as 0.5 inches of rain within a 48-hour or greater period), the following conditions shall be met prior to any vegetation management activities:

  • The maps detailing areas of historic slope instability or rock fall in the Final Geotechnical and Geological Evaluation Report for UCSF Mount Sutro shall be reviewed (Rutherford + Chekene 2013) 
  • If ground-disturbing or vegetation removal activities are proposed within or adjacent to areas of historic slope instability or rock fall, the saturation of the soils shall be estimated in the field; if muddy water drips from a handful of soil, the soil is considered saturated (Brouwer, Goffeau and Heibloem 1985) 
  • The areas of historic slope instability or rock fall shall be flagged if the moisture content of the soils is determined to be high (i.e., muddy) and ground-disturbing or vegetation removal activities shall be avoided for a minimum of 48-hours after a significant storm event to permit soil drying…”

In other words, we won’t chop down trees in the rain or when the soil is wet.

Other mitigations are palliative. They’re planning to build roads into the forest for trucks and heavy equipment, and those roads will follow the contour of the slope. The quarter-acre staging plazas – where they’ll remove trees so trucks can turn around and heavy equipment be parked – will be flattish, with a slight slope for drainage. None of this is as effective as not building these roads or bringing in heavy equipment in the first place.


The problem is, the effect of cutting down trees is a LONG TERM problem. The effect of tree removal takes years – not days, not months – to fix. In Oso, Washington, the slope gave way three years after the last tree-destruction. Here’s the story (from the article we published at the time). The tragedy was foreseen… but the regulators thought they had enough mitigations in place.

On March 22, 2014, a huge landslide destroyed the small Washington community of Oso. Rain was of course a factor, as was erosion at the base of the slope. But it’s probable that tree-cutting above the slide area was an important factor too. An article in the Seattle Times that quotes a report from Lee Benda, a University of Washington geologist. It said tree removal could increase soil water “on the order of 20 to 35 percent” — and that the impact could last 16-27 years, until new trees matured. Benda looked at past slides on the hill and found they occurred within five to 10 years of harvests [i.e. felling trees for timber].

There had been red flags before. The area was second growth forest, grown back from logging in the 1920s/30s. Over 300 acres were again logged in the late 1980s.

The first time regulators tried to stop logging on the hill was in 1988. But the owner of the timber successfully argued that measures could be taken to mitigate the risk. Eventually, the state only blocked it from logging some 48 acres, and the owners  gave in on that.

In 2004, new owners applied to cut 15 acres; when the Department of Natural Resources (DNR) objected, they halved the area and re-located the cut. DNR gave approval, subject to no work during heavy rain and for a day afterward. The tree-cutting finished in August 2005.

In January 2006, there was a major landslide 600 feet from the cut zone. The state built a log wall to shore up the slope.

The owners continued logging. In 2009, they removed 20% of the trees. In 2011, they removed another 15%. In 2014, the hillside collapsed.

The regulators were aware of the risk; they thought they were mitigating it with their restrictions and reaching a compromise with the owners. But it wasn’t enough. Destabilizing the mountainside is a long-term thing; the effects can show up in months, but it’s more likely to take years.


Our mountains not only are potentially unstable, they actually have landslides. The picture at the end of this article shows one on Twin Peaks, where rocks tumble after nearly every heavy rainy season.

The roots of the trees are helping to hold the unstable soil in place and that as the roots rot, landslide risk will increase.  It is going to be more unstable 2-3 years after the trees are removed than 2 days after it rains.  The information that instability increases over time is a little counter-intuitive.

Moreover, removing the trees takes away their ability to suck water out of the soil. If the tree-cutting is done in dry years, it may take a wet winter to trigger landslides… which would not have happened if the trees had been regulating the water and functioning as a living geotextile.

Since UCSF are not going to use herbicides on the stumps to prevent them from resprouting, they say they will grind the stumps.  That is an effective way to prevent resprouting, but it will greatly increase the instability of the soil because the heavy equipment digs down several feet into the stump to destroy the roots.  That’s another reason why they should not destroy trees where slide risk has been identified.

Anyone seriously considering the map above can only hope that UCSF will draw a better conclusion than the Washington State loggers and regulators. The planned destruction of thousands of trees – many within the first five years – could cause landslides in surrounding communities not days or months later, but years after the event.

UCSF: First, do no harm!

Posted in deforestation, Mt Sutro Cloud Forest, Mt Sutro landslide risk, UCSF, Uncategorized | Tagged , | 4 Comments

Public Comments due Sept 22, 2017 on Sutro Forest DEIR

UCSF has released a humongous 1087-page Draft Environmental Impact Report on the Plan to cut down thousands of trees in Sutro Forest. The deadline for public comment has been extended in response to a San Francisco Forest Alliance request, to Sept 22, 2017. This two-week extension from Sept 8th is a lot less than the 60 days they asked for.

[The DEIR is available HERE as a PDF document: UCSF_Mt_Sutro_DEIR_wAppendices ]

Here’s an excerpt from UCSF’s letter to San Francisco Forest Alliance:

“In response to your request, UCSF is extending the public comment period for the Draft Environmental Impact Report (DEIR) for the proposed UCSF Mount Sutro Open Space Reserve Vegetation Management Plan.  The comment period will be extended by two weeks for total of 60 days: public comments on the DEIR are now due on Friday, September 22.  All comments must be received by 5:00 p.m. on Friday, September 22, 2017.  CEQA guidelines have established that the public review period for a DEIR should not be longer than 60 days (Section 15105).

“Send written comments to the attention of Ms. Diane Wong, UCSF Campus Planning, Box 0286, San Francisco, CA 94143 or email to EIR@planning.UCSF.edu

It’s interesting that they invoke the 60-day maximum under CEQA guidelines, but ignore the guideline that says the DEIR text should be 150 pages or at a maximum, 300 pages….


UCSF will hold a public meeting on August 24, 2017

“There will be a public hearing to receive oral comments on the DEIR on August 24 at 6:30 p.m. at Millberry Union, 500 Parnassus Avenue, on UCSF’s Parnassus campus.


Posted in Mt Sutro Cloud Forest, UCSF | Tagged , , , ,

Year 9 of Mission Blue Butterfly on Twin Peaks: Mixed Results

Mission Blue Butterfly - Public Domain Image

Mission Blue Butterfly – Public Domain Image

It’s now Year 9 of the the Mission Blue butterfly project on Twin Peaks, San Francisco. In 2008, SF Recreation and Parks Department (SFRPD) started trying an attempt to reintroduce the Mission Blue Butterfly to Twin Peaks, by planting lupine and transferring in breeding butterflies from their largest existing population on San Bruno Mountain. The results so far have been mixed:

  • The lupine needs continual care;
  • The butterflies are breeding on Twin Peaks;
  • Most years, imports of Mission Blue butterflies from San Bruno continue to be needed to boost the population and its genetic diversity.

In 2017, SFRPD observers spotted 30 butterflies that were actually born on Twin Peaks. They didn’t import any butterflies from San Bruno. But the lupine, the nursery plant of the butterfly, was badly hit by funguses and hungry voles.


The Mission Blue butterfly (Aricia icarioides missionensis) is a rare subspecies of the much more widespread Boisduval’s Blue (Aricia icarioides).  The species is not endangered, but the subspecies is found only from San Bruno to Marin and is federally-listed as endangered. The largest population is on San Bruno Mountain.

Lupine is the nursery plant of the Mission Blue. It’s the only plant on which it’s known to lay its eggs and which the caterpillars eat. Mission blue eggs hatch into caterpillars which eat the lupine, shedding their skins as they grow. The larger caterpillars are tended by native ant species, who protect them from predators while benefiting from “honeydew” – sugary caterpillar pee.

Ant tending Mission Blue butterfly larva. NPS image

Ant tending Mission Blue butterfly larva. NPS image

When they’ve grown to their full size, they form their pupae near the base of the plants, or even on the soil beneath, and remain there for months (in diapause). They hatch into butterflies in spring, sip nectar from a range of flowers (including the “invasive” non-native Italian thistle: Carduus pycnocephalus), mate, and lay eggs on lupines.

These butterflies have only one generation a year and an 8-10 week flight season, becoming visible in April and May. The males live an average of 7 days, and females for 8 days. The males usually hatch before the females do, so they are ready to mate when the females appear.


Mission Blue butterflies used to inhabit Twin Peaks in San Francisco, but in 1998 a wet winter encouraged a fungal pathogen that destroyed most of the lupine plants – and the Mission Blue butterfly will not breed on anything else. The population, already small, fell until it was essentially gone. Eventually, SFRPD decided to attempt a reintroduction by planting lupine and then bringing butterflies from San Bruno Mountain.

The first batch, 22 females, was brought over in 2009. Optimistically, they hoped that this would be sufficient. But in 2010, only 17 butterflies were spotted, and imports resumed in 2011 – and in 2012, 2013, 2015, and 2016. In the graph below (covering the years 2009-2017) the dark bars show the “native-born” butterflies on Twin Peaks – i.e. ones that were spotted before transfers from San Bruno, or in years when there were no transfers. The light bars show the butterflies imported to Twin Peaks.  In 2017,  they’ve spotted 30 native-born butterflies.


[We’ve been reporting on this project for years; our most recent report is here: Mission Blue Butterfly 2016 Update: Imports from San Bruno Continue]

A report from SFRPD and its consultants on the year 2016 was issued in April 2017. It said they would not import any in 2017. But if the numbers fall in 2018, they’ll restart. The US Fish and Wildlife permit to transfer up to 20 male and 40 female butterflies each year is valid through 2020. They imported 44 butterflies from San Bruno in 2016: 15 males and 29 females.  You can read the report here: TwinPeaksProgressReportApr2017

According to that report, they were going to stop counting adult butterflies.  They planned instead to count the eggs, and calculate backward to figure how many females were implied by the number of eggs.  However, in 2017 they did in fact count butterflies, and found 15 males and 15 females in April and May.

This is the most of any year since 2009 – and definitely the most females. (However, there’s a bias because for each season we only use observations from before the transfers from San Bruno. But the transfers, too, must be made during the flight season. So in years with transfers, the local observation time is lessened and is biased to males, which emerge earlier than females.)  Despite the improvement, it suggests the population is still small enough that it cannot be considered stable or self-sustaining.

(The graph below is similar to the purple one above, but breaks out the observations – and imports – by the sex of the butterflies. The darker bars show imports, the lighter bars indicate butterflies that were born on Twin Peaks.)


It’s been a brutal year for lupine  in 2017 owing to the wet winter. There’s been a population explosion of voles, which have eaten some of the largest plants down to the ground. (A fungus has killed many of the lupine plants. Field notes describe it as anthracnose, but we’re not sure if a positive identification was made.)

In any case, this is never going to be a self-sustaining situation. They will need to keep gardening for lupine, because lupine is a plant of disturbed areas and Twin peaks isn’t disturbed.  As the report points out “unmanaged habitat degrades quickly.”

And while they can set up Mission Blue butterfly populations that are temporarily self-sustaining, in the long term they will still need to boost the population with imports.


We have a suggestion. Since lupine will have to be gardened anyway, why not grow it in containers? This should offer some protection from both voles and funguses, and provide the opportunity to optimize the soil conditions including drainage for the plant. SFRPD plants three species of lupine at Twin Peaks: Lupinus albifrons, lupinus varicolor, and lupinus formosus.

The favorite of the Mission Blue caterpillar is apparently Lupinus albifrons, or silver lupine; according to the April 2017 report, that was the only one the caterpillars were eating. And that one grows nicely in containers. The photograph below is from the website of specialist plant supplier Annie’s Annuals, specializing in rare and unusual annual & perennial plants, including cottage garden heirlooms & hard to find California native wildflowers.”

As a bonus, since container-grown plants won’t face competition from other wild plants, SFRPD can stop using toxic herbicides on Twin peaks. In 2016, they used toxic herbicides 25 times on Twin Peaks – behind only the much-larger McLaren Park (27 times) and Bayview Hill (34 times).  This included 7 applications of Garlon, possibly the most toxic herbicide the city permits.

It’s unknown whether these herbicides impact the reproductive success of the butterflies, either directly or via their ant tenders. In any case, organic lupines might be a healthier option.


These are the main issues with Garlon, in brief:

  • Garlon “causes severe birth defects in rats at relatively low levels of exposure.” Baby rats were born with brains outside their skulls, or no eyelids. Exposed adult females rats also had more failed pregnancies.
  •   Rat and dog studies showed damage to the kidneys, the liver, and the blood.
  •   About 1-2% of Garlon falling on human skin is absorbed within a day. For rodents, its absorbed twelve times as fast. It’s unclear what happens to predators such as hawks that eat the affected rodents.
  • Dogs  may be particularly vulnerable; their kidneys may not be able to handle Garlon as well as rats or humans.  Dow Chemical objected when the Environmental Protection agency noted decreased red-dye excretion as an adverse effect, so now it’s just listed as an “effect.”
  •  It very probably alters soil biology. “Garlon 4 can inhibit growth in the mycorrhizal fungi…” ( soil funguses that help plant nutrition.)
  •  It’s particularly dangerous to aquatic creatures: fish (particularly salmon); invertebrates; and aquatic plants.
  •  Garlon can persist in dead vegetation for up to two years.

If SFRPD grew the lupine in containers, it wouldn’t need to worry about the oxalis or use Garlon. At least on Twin Peaks.


We are often asked how much the Mission Blue project is costing the tax payer, so we tried to find out. This project is funded by the city, and with a three-year grant from US Fish and Wildlife Services for “habitat management” that just ended.  Data for 2008-2017 indicate the SF Rec and Parks Commission spent around $82,000. We looked at Professional Services payments to Coast Ridge Ecology, to Creekside Center for Earth Sciences, and to Liam O’Brien. There’s another consultant involved, Golden Hour Restoration Institute, but we think they were paid directly from the US FWS grant.

This of course excludes the salaries/ time of the SFRPD staff. Natural Resource Department staff are involved at every stage, from lupine planting to butterfly counting. It also excludes the cost of laying down pesticides on Twin Peaks 25 times annually.


Posted in Environment | Tagged , , , ,

Here it Comes: UCSF announces the Draft EIR for Sutro Forest

UCSF sent out a notification recently, saying that the Draft Environmental Impact Report (DEIR) for the 2017 Plan for Sutro Forest will be released on July 24th, 2017. The public will have until September 8th, 2017 to make their comments. They expect to have a public meeting on August 24th, 2017.

We will await the DEIR , analyze its contents, and report back. We do have considerable concern about the Plan itself, which we discuss here: How many trees in Sutro Forest – and what will be left?

In summary: We think UCSF’s plan is rooted in a misunderstanding of the micro-environment of this small forest, and an egregious preference for “native” plants and shrubs. It will destroy the naturalized forest that has thrived for more than a century, and would still thrive if it was not destroyed.

As we stated at the beginning of that article:

“Mount Sutro is a very difficult site. Its soils are shallow, its rocks unstable. It’s very windy. Few trees survive those conditions. Nevertheless, the eucalyptus forest has naturalized there for over a century – nearly 125 years now – and taken on the characteristics of an old-growth forest. This success has only been possible because of the interdependent ecology of the forest. The roots are intergrafted, which both helps distribute nutrients and moisture, and to provide physical support to trees. As Peter Wohlleben points out in his book, the Hidden Life of Trees, trees in a forest are different from individual, standalone trees.


The tree density changes the conditions in the forest, reducing wind speeds and providing shelter not just for other eucalyptus, but also for other trees species found in the forest: Monterey cypress, Monterey pine, coast redwood, plum, cherry, California bay, coast live oak, willow among others. It creates a tiny microclimate inside it.

pix9 072 forest

“This is why the new Plan for the forest – removing most of the healthy living trees and nearly all the dead ones – will destroy the forest’s ecosystem and very likely the forest itself.

“UCSF, which has declared the forest to be in poor condition, will doubtless blame the drought and pathogens. In fact, it’s the thinning – including removing understory – and the tree removal that rob the forest of its resilience. A forest that’s thrived for 125 years may be destroyed in a decade.”

Read the remainder of that article HERE.

Posted in Mt Sutro Cloud Forest, UCSF | Tagged , , | 1 Comment

Butterfly Count in San Francisco – 2017

This year’s sunny butterfly count day – June 18th, 2017 – made up for last year’s dismal fog. Eighteen spotters in eight groups, led by butterfly maven Liam O’Brien, counted a record number of butterflies: 1435 or 1440, (we’re still trying to verify which, but realistically it doesn’t much matter). The count hasn’t exceeded a thousand before.

Illustration of a Mourning Cloak butterfly - public domain via Wikipedia

Illustration of a Mourning Cloak butterfly

They also counted 29 species, up from the more usual 24-26. One of them, the Mourning Cloak, hasn’t been counted before (at least since 2010). In all, 34  species have been recorded in San Francisco in the 7 years we’ve been following the data, but some don’t show up every year.


Each year, the North American Butterfly Association (NABA) sponsors the July 4th series of butterfly counts at locations all across the US. Volunteers go out up to one month before or after July 4th to count butterflies in specific locations.

We’ve followed the San Francisco butterfly count since 2010, with a gap in 2015 when we found no published data. (If data are made available, we’d be happy to publish it.)   The results for earlier years are here: 2010, 2011, 2012, 2013, 2014, and 2016.

The San Francisco count is tricky; San Francisco gets fog in summer and butterflies tend to lie low on foggy days. (The picture of Sutro Forest below shows typical summer weather in San Francisco.)

The 2016 count, on June 4th, had bad luck with the weather, with a persistent fog and only sporadic sunshine. The spotters were able to find 24 species, the same as in most years, but only 499 individual butterflies. In 2017, by contrast, spotters found 1435-1440 butterflies of 29 species.

Counts in recent years include Angel Island and Yerba Buena Island, both of which have slightly different species from San Francisco city. In 2016, three of the species were counted only on the islands: The Pipevine Swallowtail on Angel Island and Yerba Buena (though other, non-count reports say it has been seen on Mount Sutro!); the Common Wood Nymph and the Rural Skipper on Angel Island. In 2017, the islands yielded California Sisters, Rural Skippers, and the Common Wood Nymph. (The Pipevine Swallowtail is also on the “spotted” list, but this year’s notes don’t mention it as being confined to the islands.)


Two butterfly species accounted for half the sightings in 2017:  The Cabbage White, and the Echo Blue.  The top ten butterfly species accounted for 86% of the count numbers.

Cabbage White sitting on Oxalis

The Cabbage White butterfly topped the charts this year, as it has in five of the seven years for which we have data. There was a record sighting of 487 individuals, far exceeding the 378 in 2011. This butterfly especially likes brassicas, in the cabbage and mustard family like San Francisco’s wild mustard.

Source: Katja Schultz, Wikimedia Creative Commons

The second position this year went to the Echo Blue, a small blue butterfly. It’s shown up in third place twice before. Online information about this butterfly is sparse; its larval food plant seems to be ceanothus and a variety of others including, possibly, blackberry. If this proves accurate, it may explain why the species is seen so often in San Francisco – we have a lot of Himalayan Blackberry, which is an excellent habitat plant for a lot of wildlife of all sizes and species.

The third place went to the spectacular Anise Swallowtail, one of our prettiest butterflies. It breeds on fennel, a non-native plant introduced for its culinary and medicinal properties, but now hunted as a weed by San Francisco’s Natural Resources Department. Fortunately, fennel is still abundant in the city, and so are these butterflies.

Other highlights:

  • For Anise Swallowtails, this count bettered the National High count of 2011!
  • The Monarch butterfly showed up again, which is pleasantly unusual since these butterflies more usually overwinter at the coast and fly inland in summer. Maybe they’re adapting to year-round residence? Its main locations seem to be The Presidio and Treasure Island/ Yerba Buena.
  • The Mylitta’s Crescent, which feeds mainly on thistles, made a better showing this year.
  • The Western Pygmy Blue, common elsewhere but rare in San Francisco  showed up this year. It’s the smallest butterfly in the US, only a half-inch across and is copper-colored with only tiny bits of blue. It’s only been recorded once before, in 2012.
  • The Mourning Cloak butterfly – a handsome dark-brown butterfly with a yellow edge to its wings is rare locally though abundant elsewhere. It showed up in the count for the first time. This butterfly lives almost a year, and is a strong migrator so it shows up all round the world. Though the butterfly is gorgeous (its British name is “Camberwell Beauty”) its caterpillar – the Spiny Elm Caterpillar – chomps through tree leaves, sometimes destroying the trees. It prefers hardwood forests and cold winters, which may explain why we don’t see much of them in the city.


If, like us, you like to see the data in detail, here is our spreadsheet compiling the butterfly count numbers from 2010-2017 (except for 2015, the missing year). We’ve arranged them in alphabetical order for convenience.WHY NO MISSION BLUES?

What about the Mission Blue butterfly that SF Recreation and Parks Department has been trying to introduce on Twin Peaks?  Well, the count really doesn’t provide any information because those butterflies have an 8-10 week flight season in April and May. So unless the Count is very early and the flight season delayed, Mission Blues are unlikely to appear in this record. We’ll report on them separately when we have all the data.

Posted in Environment | Tagged ,

Ecological Novelty is Nature’s Future

This thoughtful article and guest post by Professor Mark Davis was first published in Death of a Million Trees (which fights unnecessary tree destruction in the San Francisco Bay Area), and subsequently on the website of the San Francisco Forest Alliance. It is reprinted here with permission.


Mark Davis, Macalester College

Mark Davis is Professor of Biology at Macalester College in St. Paul, Minnesota.  He is one of the first academic ecologists to publicly express skepticism of invasion biology.  His book, Invasion Biology, was published by Oxford University Press in 2009.  It was the first critique of invasion biology written by an academic scientist. Professor Davis cites the many empirical studies that find little evidence supportive of the hypotheses of invasion biology. 

In 2011, Nature magazine published an essay written by Professor Davis and 18 coauthors entitled, “Don’t Judge Species on their Origins.”  This essay suggested that conservationists evaluate species based on their ecological impact, rather than whether or not they are natives.  The essay initiated an intense debate in the academic community of ecologists that continues today. 

Professor Davis spoke at the Beyond Pesticides conference in Minneapolis at the end of April 2017. (Video available HERE) He described invasion biology as an irrational ideology that is based on nostalgia for the past and a belief that wildlands are being damaged by “alien invaders.”  In fact, the perceived damage is largely in the eye of the beholder, depending largely on one’s membership in a group benefiting from the nativism paradigm, such as chemical manufacturers, conservation organizations, government agencies, and employees.  Some academic careers are also at stake.  Futile attempts to re-create historical landscapes always have the potential to make things worse.  In many instances, it is more sensible to change one’s attitude about the changing landscape than trying to change nature.

Mark Davis speaking at Beyond Pesticides conference, April 2017

We invited Professor Davis to write a guest post for publication on Million Trees.  We asked him to express his opinion on these questions: 

  • Has the status of invasion biology changed much since Nature published your essay 2011?
  • Has increased knowledge of climate change had an impact on the status of invasion biology in academia?
  • What do you think is the future of invasion biology both as an academic discipline and as public policy?

Professor Davis’s guest post addresses these questions.  We are grateful to Professor Davis for his many contributions to our understanding of the fallacies of invasion biology and for his thoughtful guest post.

Million Trees

Competition to define nature

In the past few years, a new perspective has been taking hold in the field of ecology.  Referred to as ‘ecological novelty’ it emphasizes that many factors are producing ecologically novel environments.  Climate change (which includes changes in temperatures and patterns of precipitation), increased atmospheric carbon dioxide, which affects photosynthetic rates, increased atmospheric deposition of nitrogen (the whole earth is being fertilized due to the increased nitrogen we are pouring into the atmosphere), and the introduction of new species are all rapidly changing our environments.

A strength of the term ecological novelty is that unlike the invasion vocabulary it is simply descriptive.  It simply states that ecosystems are changing and are different than they were in the past, even the recent past.  It says nothing about whether this change is good or bad.  In this paradigm, species can be referred to as novel species, new arrivals, or long-term residents.

The less biased ecological novelty paradigm differs dramatically from the more ideological nativism paradigm.  It differs in the language it uses and it differs in the implied direction that land management should proceed.  More generally, it forsakes the normative atmosphere that permeates restoration ecology, conservation biology, and invasion biology, all of which have been substantially guided by the nativism paradigm.

The Sutro Forest in San Francisco is a good example of a novel ecosystem. It is a thriving mix of native and non-native species. Much of it will be destroyed by the irrational belief that native species are superior to non-native species.  Million Trees

Currently, invasion biologists are trying to discredit ecological novelty as a valid or valuable perspective.  This is hardly surprising since the ecological perspective would displace the nativism paradigm, and many stakeholders have much to lose if the nativism paradigm were abandoned, e.g. chemical companies, restoration and management companies, local, state, and national agencies, to name just a few.  Not surprisingly, articles trying to shore up invasion ecology and to keep it relevant have been common in recent years.

While the public may not be aware of it, there exists a heated competition to define natureWhich side wins will significantly determine how nature is managed.  Given that the redistribution of species is only going to increase in upcoming decades, it is hard to imagine that people will still be so preoccupied with origins by the middle of the century.  Like the notion of wilderness, the nativism paradigm is more of a twentieth century concept, while the construct of ecological novelty is more fitting for the twenty first century.

Undoubtedly, nativist groups will still exist and will still be preoccupied with trying to restore their vision of the past.  But, due to the number of species being moved to new regions, much more attention likely will be given to the function of species than their origins, if only for pragmatic reasons.  For people coming of age now, cosmopolitanization is the new normal, both with respect to people and other species.  We will still carry our predispositions to divide the world into us and them, but it should be clear to most that the nativism perspective will be obsolete and that beyond the creation of museums, restoring the past will not be possible, whether a city or a forest.

Currently Earth is the only planet we know of where life exists.  In this context, the desire and practice of declaring some species as aliens, exotics, or invaders seems sadly provincial and even unseemly.  Roman playwrite Publius Terentius Afer (aka Terence) wrote in his play Heauton Timorumenos, “Homo sum, humani nihil a me alienum puto”, or “I am human, and nothing of that which is human is alien to me.” To those who still see such value in distinguishing native from alien species, I say, “I am of the planet Earth and nothing of that which is earthly is alien to me.”

Mark Davis

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April Visit to Beautiful Sutro Forest

“I would love to see Sutro forest,” said the out-of-town visitor. “I’ve heard so much about it!”

So when the welcome rain cleared into welcome sunshine, we headed up the new trail at the Pumphouse on Christopher Drive.

It doesn’t provide the immediate immersion of the old 101 Christopher trail, where within 10 feet the houses were hidden and you were wholly among the trees. But gradually we left behind the houses and the dormitories and found ourselves in the forest.


Trail conditions were good – damp to wet, but not slushy. Good for walking, and pretty good for mountain-biking. The rain has left everything lush and green once more, and the forest was utterly beautiful.

Despite the thinning and the tree-felling, nature is resurgent.

The trails were picture-book pretty.

We found a few others out on the trail, though it was a weekday morning  – joggers, people with dogs, a very few hikers like us. Also enjoying the forest: Mountain bikers. As usual, they were courteous and considerate.

Though we’ve heard stories otherwise, we ourselves have only had one encounter with a rude bicyclist – and that was five years ago.


It wasn’t just the trees, though they were of course the main event: It was the whole forest ecosystem.  All round us, the understory was bursting with life. Little patches of flowers – forget-me-nots, Roberts geraniums, Douglas iris – added specks of color to the myriad shades of green.



This thistle’s leaves had such dramatic markings that it demanded a photograph.

We found a profusion of Miners Lettuce, and on some slopes, nasturtiums. We collected a few handfuls for a salad.

There were a lot of birds, flying and calling. But the only ones that sat still for a picture was this Mourning Dove…

… and this robin.


Most of the forest is still reasonably secluded, giving it the feeling of being in a different world outside the houses and urban buzz. But there are areas where it’s now quite thin and you can see the city below: The Inner Sunset District, and the green band of Golden Gate Park.

If you love this wild forest, with its ecological novelty and plants from all over the world, now is the time to make your memories and take your photographs. If things go according to UCSF’s plan, tree-cutting and massive understory removal could start this August.





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Peter Ehrlich, 1948-2017

Peter Ehrlich was the Chief Forester at the Presidio, and sat on UCSF’s Technical Advisory Committee for Sutro Forest. Tragically, he died in a bicycle accident on May 2, 2017.  The Presidio is holding a community work day in his honor on May 21, 2017 at the Spire in the Presidio, between 10 a.m. and 1 p.m. Click here for Registration and details.


This tribute to Peter Ehrlich was written by Dee Seligman, formerly Interim President of San Francisco Forest Alliance. It is republished here from their website at SFForest.org.

Peter Ehrlich (left), with Ron Proctor, Jacquie Proctor, and Larry Seligman in the Presidio – Dec 2016


Tribute to Peter Ehrlich

by Dee Seligman

On Sunday, May 21, from 10 am to 1 pm, the Presidio Trust will host a Community Stewardship Day in honor of Peter, where staff, volunteers, and friends can celebrate Peter by caring for the trees in the cypress grove surrounding Spire. We’ll pause at noon for reflections about Peter. Refreshments will be provided. We hope as many SF Forest Alliance supporters as possible will attend this event to honor Peter.

Peter Ehrlich was a mensch. This Yiddish expression describes a human being, one in the fullest sense of the word with integrity, humanity, and worthy of emulation. It’s an apt description of Peter, the Chief Forester of the Presidio and previously the Manager of the tree maintenance programs in all of San Francisco’s parks for 15 years, who died unexpectedly in a biking accident about a week ago.

This small man from the Bronx with a big heart, a passion for trees and birds, a man of science and of literature, had a special connection to the San Francisco Forest Alliance (SFFA). With his mischievous smile, ironic perspective, and regard for classic literature, he reached out to us as a group, and to many others in the Bay Area. Caring about trees was the common denominator to being Peter’s friend and ally.

He said he learned as a kid in the Bronx to stand up for what he believed in, and Peter believed in trees—boy, did he ever! He loved trees—all trees. He did not differentiate between native and non-native but found value, inspiration, and function in all trees. He understood equally well the physical comforts provided by trees but also, what he called, “the aesthetic experience” of forests.

Peter Ehrlich (left) and Ron Proctor planting trees in Presidio

He did his best to protect all trees. In the Presidio, which is controlled by the federal government through the National Park Service, there is forest management and ongoing rejuvenation, directed by Peter. He replaced some blue gums in the Presidio with related species of eucalyptus when absolutely necessary.

However, within the municipal parks of San Francisco, such as in Natural Areas like Mt. Davidson, there has been no ongoing rejuvenation. Peter looked out for the eucalyptus in these areas, too, by working with SFFA to evaluate the trees of Mt. Davidson and Mt. Sutro. He walked both forests with SFFA leaders at separate instances and documented in writing that he did not find them unhealthy nor unusually at risk due to drought, insects, or any of the other reasons dredged up by native plant advocates for the Natural Areas Program. He supported our point of view in a letter to the Planning Commission and to Rec and Park Commission when the EIR came up for certification.

He spoke at conferences, gave local talks, and guided walks in the Presidio. I witnessed his perceptive service on the Technical Advisory Committee for UCSF on Mt. Sutro, where he asked definitive questions, such as whether there were risk ratings done for all the trees on the mountain? He emphasized that “lack of vigor”  is different than “hazard,” in other words asking for more nuanced information from any assessment of the trees. In fact, Peter’s questions prompted the assessing arborist to explain that they had two different rating systems: one for individual trees in high-use areas, but another for all the rest of the trees. This fact was unlikely to have been revealed without his astute questions.

Peter did not mince words. After reviewing an early draft of an Urban Forestry Council’s proposed document on “best management practices for the urban forest”, he advised us that “if the goal of the document was conversion [i.e., of the type of species in the forest], it should be clearly stated as such.” He advised against references to fire or other objectives “if the real goal is type conversion.” He questioned, “What are San Francisco’s ‘priorities’? What are San Francisco’s endangered species on Mt. Davidson and Mt. Sutro? The Presidio has four. What are the endangered species on Mt. Sutro and Mt. Davison? The ‘sensitive species’ are impossible to define. The word ‘sensitive’ with respect to species is overused.”

And he would not accept easy answers. For example, “thinning,” as proposed by the Natural Areas Program is not a universal cure-all. He said: “Thinning is presented as an event that is self-explanatory. It is not, as thinning must be done, if it is deemed necessary, with low-impact techniques that preserve residual trees. A contractor without tree protection constraints could do a lot of damage. In fact, even with tree protection requirements in place, an on-site monitor would be necessary to make sure residual trees were not negatively impacted.”

Another glib answer he rejected was Rec and Park’s explanation that the eucalyptus were all “dying due to drought.” He differentiated between blue gum eucalyptus having no leaves at all, possibly signifying a lack of regeneration, from blue gums having a decreased canopy percentage, not necessarily a sign of poor health. In dry weather, blue gums often protect themselves by shedding some leaves, which would transpire water, and growing epicormic sprouts instead.

Although somewhat constrained by working in a politically sensitive position in the Presidio, he was clear-eyed about the environmental politics of San Francisco. Nothing could be more telling than a comment he once sent me about the long, contentious, and circuitous process to certification taken by the Significant Natural Resource Areas’ Management Plan (formerly known as SNRAMP, now called NRAMP, or Natural Resource Areas Management Plan).

Peter said, “As Shakespeare wrote in King Lear: ‘Tis the time’s plague when madmen lead the blind.’”
We all miss Peter very much. 

Peter also loved wildlife and birds. A few years ago, he sent us some pictures of young Great Horned Owls in a nest in the Presidio. He gave us permission to use them then, and we publish them here in grateful remembrance.


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