Bees in Glen Canyon – Update

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

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


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

exposed hive with bees (Photo- Scott Mattoon)

Exposed hive with bees (Photo – Scott Mattoon)

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

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

revived hive

Revived hive – Photo (c) Janet Kessler

the bee tree that was killed has bees again

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

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

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

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

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

the remaining bee tree

The old bee tree. Photo (c) Janet Kessler

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

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

Fighting The NAP Nativist Agenda

Once in a while, we want to affirm the values that San Francisco Forest Alliance stands for. We’re a grass-roots organization of people who love nature and the environment, pay taxes responsibly, and want access to our parks and wild places – with our families.

Citizens care about their city Parks, and want to keep healthy trees and to open access to natural areas. Citizens expect city management to act responsibly and in the public trust, for FAIR allocation of 2008 Clean & Safe Neighborhood Parks Bond funds.

SF Recreation and Parks Department (SFRPD) and particularly the Natural Areas Program (NAP), obsessed with Native Plants, is cutting down trees, restricting access, using more toxic herbicides than any other section of SFRPD (excluding Harding Park Golf Course), and using financial resources that could better be used for things our city’s residents really want.


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


What we stand for can be summarized in four key areas: Trees, Access, Toxins, Taxes.


Improvements to the Glen Canyon Park Playground?

Last month we reported on the status of the Glen Canyon Park Playground Improvements.
We mentioned the new playground and that it will not be the same as it was:-  a steep staircase to the slide and bushes that were at the top – now gone. The kids loved that slide … they played games of imagination and adventure there. Instead of a quirky playground that used the advantages of the site, there’s a standard-issue place that could have been built anywhere. And the wonderful climbing tree the children loved, which was behind the Rec Center – it is now gone.

In honor of the Glen Canyon Park Playground re-opening on March 15th, we are re-issuing a relevant YouTube video

Help us save the urban forests in our San Francisco Parks

Glen Canyon Park: One Year after Start of Tree Destruction

The Glen Canyon Playground and Tennis Court Project – as the city is calling this – is nearly completed. In February or March 2014 there will be great fanfare at the completion of this project.

Video update to the Glen Canyon Park tree demolition project

Is it an improvement? Well, there is a new playground at least, but it will not be the same as it was: a steep staircase to the slide and bushes that were at the top – gone. The kids loved those; they played games of imagination and adventure there. Instead of a quirky playground that used the advantages of the site, there’s a standard-issue place that could have been built anywhere.  And the wonderful climbing tree the children loved, behind the Rec Center – also gone. The new kids will not know what they missed.

The City Arborist report stated that only 1 tree was truly hazardous, yet 42 trees were destroyed. Equally troubling is the deliberate relocation of tennis courts that destroyed 11 healthy and majestic Eucalyptus guarding the Park’s entrance.

Question: Why was there no attempt to incorporate these trees into the overall design goal that could have been achieved without sacrificing space for the playground and ball field?

Answer: San Francisco taxpayers “purchased” a native plant garden as part of the project and ensured all those “poor suitability / non-native” trees were eliminated.

Functional, Beautiful Ecosystems Should Be Left Alone; the Parks need maintenance, not destruction.


While you are on YouTube, why not Subscribe to our Channel and keep up with our latest videos by the San Francisco Forest Alliance?



Merely follow step one or two to Subscribe to our Channel:

Step 1) Do you have a YouTube account? OK then, its easy to subscribe …just click this link add_user=SFForestAlliance

Any users who are logged into YouTube already need only to click that link and then confirm the subscription and they’ll be added to our Channel.

Step 2) Not on YouTube account yet? All you need to do is watch one of our YouTube videos, click on the”Subscribe” button / link, which is directly across from the Name of our Channel: San Francisco Forest Alliance. Or, the “subscribe” button may appear below the video title.

The last step is to sign in to your Google account or register with a Gmail, YouTube or Google+ account.

How Children Draw ‘Save the Eucalyptus Trees’

Someone sent us these amazing ‘Save the Eucalyptus’ posters, produced by the children in political artist and printmaker Doug Minkler’s art class. They’re used with permission. [Edited to add the artists' names.]

(If your kids are drawing pictures of San Francisco’s wild lands or its birds and animals and trees that you’d like displayed, we’d be happy to use them on this site. Please attach them to an email to SFForestNews at and be sure to give permission for us to put them up.)

Save-the-Eucalyptus sm

Save the Eucalyptus by Desiree Minkler

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

The Morning Before the Loggers Came – Desiree Minkler


Whoos For Us? – Tacy Prins Woodlief

no-more-homeless-owls sm

No More Homeless Owls – Blake Bogert


Poisoned Water – Ayumi Beeler

Audio Talk (YouTube) Against the Needless Destruction of Urban Forests

You are invited to hear comments by Ariane Eroy, a supporter of Sutro Forest, trees, and the environment, on KPFA radio (broadcast date: 1/2/2014).

Ariane speaks in support of the effort to save the Sutro Forest and challenges East Bay residents to get UC Berkeley to scale back its destructive project tree-removal in East Bay hills, part of a huge program that threatens half a million trees.  This 2 minute, 30 second audio broadcast includes pictures of the Mt Sutro forest.


While you are on YouTube, why not keep up with our latest videos by the San Francisco Forest Alliance.


 Just follow step one or two to Subscribe to our Channel:

Step 1)  Do you have a YouTube account? OK then, its easy to subscribe …just click this link

Any users who are logged into YouTube already need only to click that link and then confirm the subscription and they’ll be added to our Channel.

Step 2)  Not on YouTube account yet? All you need to do is watch one of our YouTube videos, click on the”Subscribe” button / link, which is directly across from the Name of our Channel: San Francisco Forest Alliance.   Or, the “subscribe” button may appear below the video title.

The last step is to sign in to your Google account or register with a Gmail, YouTube or Google+ account.

California Invasive Plant Council‏: Remove Blue Gum Eucalyptus from the List of Invasive Plants

This is a guest post, republished from Death of a Million Trees:  2013 Progress Report | Death of a Million Trees

2013 PROGRESS REPORT from ‘Death of a Million Trees

As we approach the end of the year, let’s review the progress we’ve made in 2013 on our mission to save healthy trees and prevent the unnecessary use of herbicides in our public open spaces.  It’s been a good year:

  • University of California San Francisco (UCSF) has decided to scale back its plans to destroy about 30,000 trees and the forest understory on Mount Sutro.  They have also made a commitment to NOT use herbicides in the forest in the future.   (Visit Save Sutro for details.)
  • UCSF’s plans to destroy most of the trees on Mount Sutro were criticized by the mainstream press, i.e. the New York Times and Nature magazine.
  • Thousands of citizens in the Bay Area signed our petitions to object to the Mount Sutro project and the projects in the East Bay which FEMA is considering funding.  Likewise, critics of these destructive projects overwhelmed a handful of supporters at the public hearings about these projects.
  • Marin County Open Space District and Parks Department engaged a consultant who reported that “vegetation management” projects result in more non-native plants and that managers of public lands in the Bay Area no longer consider it feasible to eradicate all non-native plants in open spaces.

The California Invasive Plant Council has noticed the public’s opposition

Anise Swallowtail butterfly in non-native fennel

Anise Swallowtail butterfly in non-native fennel

Another barometer of our progress is the latest edition of the newsletter of the California Invasive Plant Council (Cal-IPC) which is available here.  Readers are immediately alerted to a change of attitude by the photograph on the cover of a native butterfly and a native bee feeding on a non-native thistle.  As anyone who has debated the issues with native plant advocates or read their propaganda knows, they usually deny that non-native plants are useful to native insects.

The cover photograph makes a concession and sets the tone of the Cal-IPC newsletter. [Edited to Add: The Cal-IPC cover photograph shows native insects - the Pipevine Swallowtail butterfly, and a native species of bee - feeding on the non-native bull thistle.]

Bumblebee on Cotoneaster, Albany Bulb

Native bumblebee on Cotoneaster, Albany Bulb

The opening message from the Cal-IPC Executive Director begins with a quote fromInvasive and Introduced Plants and Animals:  Human Perceptions, Attitudes and Approaches to Management:  “…intervention in conservation practice hides behind a veneer of pseudoscience and certainly challenges democratic processes.”    We told our readers about that book and ironically we selected the same sentence to describe its conclusion.  So, have we found some common ground with native plant advocates, as represented by Cal-IPC?

Not quite.  The title of the Director’s message is “A ‘cottage industry of criticisms.’”  This is the phrase used to describe those who criticize invasion biology.  Speaking for Million Trees and those with whom we collaborate, it is not accurate to call us an “industry” because we derive no economic benefit from our advocacy on behalf of non-native species.  In contrast, the ecological “restorations” that are based on the assumptions of invasion biology are an industry.  The economic interests of those who are employed by “restoration” projects are one of the reasons they cling desperately to the ideology that supports their employment.

The Cal-IPC Director tells us that, “Though they raise critical issues to address, such critiques underestimate the degree to which these issues are already being addressed.”  He claims that“Cal-IPC’s workshop asked participants to consider ecological services offered by top weeds of concern.  Weighing such information will become increasingly important as land stewards design management approaches to meet long-termconservation goals in an age of great environmental change.”

Cal-IPC can demonstrate this new management approach

What an excellent idea!! And we hope that Cal-IPC will start that new approach by revisiting its outdated assessment of Blue Gum eucalyptus which presently contains nothing but demerits, most of which are not even accurate.  If Cal-IPC takes into consideration the significant ecological services provided by Blue Gum eucalyptus, they will surely remove it from their long list of “invasive species.”  Here is a brief list of the ecological services provided by Blue Gum eucalyptus in California:

  • These large, hard-wood trees are storing millions of tons of carbon which will be released into the atmosphere as carbon dioxide when they are destroyed and as their wood decays on the ground, thereby contributing to climate change.
  • These trees are expected to live another 200-300 years, which means that this ecological service would be needlessly terminated by their premature destruction.
  • These trees are providing windbreaks on windy hills and for agricultural crops.
  • The roots of these trees stabilize the soil on hills that will erode when the trees are destroyed and roots die.
  • These trees provide the over-wintering roost of tens of thousands of monarch butterflies.
  • These trees are a source of winter nectar for bees, butterflies, and birds.
  • These trees are the nesting and roosting habitat of raptors and owls.

We urge Cal-IPC to demonstrate its professed willingness to consider the benefits of non-native species by revising their assessment of Blue Gum eucalyptus, which is rarely invasive and is providing valuable ecological services to animals as well as humans.  

Glen Canyon Park: Nine Months after Tree Destruction

Video update to the Glen Canyon Park tree demolition project

San Francisco’s Wreck and Park Department is now calling this “The Glen Canyon Playground and Tennis Court Project“.  This is only a continuation of the mis-information that have been provided as the Glen Canyon Park Improvement Plan (note: they are spending $5,800,000 of the 2008 Park Bond Fund for Glen Canyon “renovations”).

You will be seeing in this new video a bit more than just preparations for a new playground and 2 new tennis courts. The damage to Glen Canyon Park by the city is significant; we thought the project was the “removal and pruning of select trees”, but it is much more than that. And the wonderful children’s climbing tree is now gone; it once stood behind the Rec Center.

Here is a reminder [Beginning of Glen Canyon Park tree destruction] of what was once there. On January 10, 2013 we reported on the start of this demolition project by the city. The grand eucalyptus trees at the Elk Rd entrance, over a century old, were quickly destroyed. Hundreds of other trees in the canyon, the ones the children love and climb in, the ones the birds nest in and bats hide in, the ones that feed the and protect the wildlife of this canyon – all will be gone by the time this project is completed next year.

all the trees in this picture will be gone in a few days

All these trees are gone

Tree 22 with kids

There’s bare ground where this wonderful climbing tree stood

Before tree removal

Before tree removal and so different now


Long Lost Manzanita Brings Newfound Problems (Westside Observer re-post)

Editor Notes:
This is a reposting of  an important story about the plan to reintroduce Franciscan manzanita into City park land – and now also private property along Marietta Drive in the Miraloma Park neighborhood. We also want to refer to important background information about the ambiguity of the taxonomy of manzanita.  Click here


George Wooding

George Wooding

By George Wooding

Westside neighbors are concerned a rare manzanita plant will have a profound impact on neighborhood habitats and uses.

franciscan manzanita

Franciscan manzanita

In 2009, a 14-foot wide Arctostaphylos franciscana (Franciscan manzanita) — a plant thought to be extinct in the wild for the last 60 years — was discovered in the Presidio during the 2009 Doyle Drive rebuild. It was deemed to be the last wild Franciscan manzanita and immediately labeled a genetically-unique plant that needed to be saved.

“Does it make sense for over six percent — 318 acres — of City-managed park land to be permanently committed to planting an endangered species that can be readily purchased in nurseries?”

Flash forward to 2013. In just four years, 424 plants genetically identical to the Franciscan manzanita found in the Doyle Drive construction site have been propagated via cuttings, according to Betty Young, director of nurseries for the Golden Gate National Parks Conservancy, who is coordinating the effort.Manzanita habitat

On September 5, 2012 the U.S. Fish and Wildlife Service issued its proposed designation of 11 areas in San Francisco as critical habitat for the endangered manzanita plant. That proposed designation includes part of Mt. Davidson. Critical habitats are places where endangered plants are either known to have existed in the past, or are places that provide what a plant needs to survive.

By June 28, 2013 the Fish and Wildlife Service designated 318 acres in San Francisco as critical habitat for the plant.

Critical Habitat vs. Eminent Domain

One of the new critical area habitats for the manzanita plant includes the area along Marietta Drive facing O’Shaughnessy Hollow all the way down along O’Shaughnessy Boulevard, and includes all of the open space known as Reservoir Lands at Glen Park, which has trails currently accessible on Marietta Drive.

The designation of 3.2 acres of private property directly below Marietta Drive as critical habitat has been controversial. The backyards of 22 homes on Marietta Drive are now designated as critical habitat for the Franciscan manzanita. The government cannot use critical habitat designations to take over or control property rights.

However, at the September 23 West of Twin Peaks Central Council meeting, it was stated that the Fish and Wildlife Service may use “eminent domain” to control the 3.2 acres for possible reforestation. But according to Robert Moler, Assistant Field Supervisor for External Affairs for the Fish and Wildlife Service, “Activities on private lands that don’t require Federal permits or funding are not affected by a critical habitat designation.” In other words, private citizens will still be able to control 100% of their land regardless of a critical habitat determination.

manzanita brush

“Eminent Domain is completely different than a critical habitat designation. Eminent domain is the power of the state to seize private property without the owner’s consent. A critical habitat designation only delineates the best places an organism can survive.”

NAP Clams Up

All of this Mt. Davidson land is controlled by the SF Rec & Parks (RPD). The RPD’s Native Area Plants Department (NAP) will be overseeing the replanting of the Franciscan manzanita throughout this area. Unfortunately, NAP has not met with neighbors to discuss its plans to reestablish the manzanita. Nor has any government agency contacted the neighborhoods about the manzanita. Calls to NAP Director, Lisa Wayne, were not returned.

As with other NAP projects, public access to large areas may become off-limits so that the Francisco manzanita can become reestablished. Neighbors are worried that large sections of Mt. Davidson might be closed to the public for years while the wild Franciscan manzanita is getting established. NAP has been completely silent on whether it will designate open space areas as being off-limits, and for how long.

It cost San Francisco $205,075 to dig up and replant the last remaining wild Franciscan manzanita, including $100,000 to pay for the “hard removal,” $79,470 to pay for the “establishment, nurturing and monitoring” of the plant for a decade after its “hard removal,” and $25,605 to cover the “reporting requirements” for the decade after the “hard removal.”

The Franciscan manzanita is also a commercially cultivated species of shrub that can be purchased from nurseries for as little as $15.98 per plant, and have been available for purchase in nurseries for about 50 years. The plants are propagated by taking cuttings and, therefore, are presumed to be almost genetically-similar.

The last wild Franciscan manzanita may have been found, but it may be a hybrid of the manzanita plants found in nurseries. Recent taxonomic revisions have established Franciscan manzanita as a separate species, based primarily on genetic comparisons, including the fact that Franciscan manzanita has 13 pairs of chromosomes, while its closest relative (A. montana ravenii )  has 26 chromosome pairs.

Manzanita seeds are germinated by fire, but the exact relationship between germination and fire isn’t known. This is why the plant is constantly cloned. The plant also requires full sunlight. How many trees will NAP cut down to provide the Franciscan manzanita with full sunlight?

The Francisco manzanita is listed as an endangered species. The Endangered Species Act listing for the rare bush means anyone who removes or tampers with the plant could face criminal prosecution and fines. The designation also qualifies the plant for federal conservation funds.

Does it make sense for over six percent — 318 acres — of City-managed park land to be permanently committed to planting an endangered species that can be readily purchased in nurseries? How will the Franciscan manzanita be able to survive without fire?

Neighbors need to know what is happening with the 318 acres of San Francisco private and public land that will be used to replant the manzanita, and how the critical habitat determination will impact public open space. RPD outreach to neighborhoods continues to be poor and disingenuous. NAP has stonewalled the public far too long and must be required to meet with Westside neighbors.

by George Wooding, Midtown Terrace Homeowners Association

Monarch butterflies in California need eucalyptus trees for their winter roost

Guest Post:   Death of a Million Trees

Monarch butterflies in California need eucalyptus trees for their winter roost | Death of a Million Trees.

Monarchs are probably the best-known butterfly in North America, partially because they are distinctively beautiful, but also because of their epic migration.  East of the Rocky Mountains, monarchs migrate from the Canadian border and the Atlantic Coast to spend the winter months in fir trees in Michoacan State in Mexico.  West of the Rockies, monarchs migrate from the Canadian border and the Pacific Coast to overwinter along the coast of California from Mendocino County to San Diego County, near the Mexican border.

Monarch Butterfly.  Creative Commons

Monarch Butterfly. Creative Commons

No single monarch makes the entire journey.  It takes two to three generations of monarchs to make the entire round trip.  How each successive generation knows the route remains largely a mystery, although theories exist.  There are a couple of fascinating books about the migration that we recommend to our readers.  Four Wings and a Prayer is a book about the 38-year effort of Canadian entomologists, Fred and Norma Urquhart, to understand the migration.  It reads more like a suspenseful mystery than the non-fiction book that it is.  Flight Behavior is by Barbara Kingsolver, one of our favorite novelists because nature is often the subject of her work.  Although it is fiction, it has been carefully researched by Kingsolver who studied biology before becoming a writer.  It is engaging both as a cautionary tale for environmentalists and as a personal redemption story.

The western migration of the monarch

Monarch butterflies roosting in eucalypus tree.

Monarch butterflies roosting in eucalyptus tree.

We will focus on the western migration of the monarch because that’s our neck of the woods, but also because this migration is one of the reasons why many people who care about nature and wildlife object to the destruction of eucalyptus trees.  Eucalypts are the preferred trees for over-wintering monarchs“Three types of trees were used most frequently by roosting monarchs:  eucalyptus (75% of the habitats primarily Eucalyptus globulus), pine (20% of the habitats; primarily Pinus radiata), and cypress (16% of the Cupressus macrocarpa).  Twelve other tree species were identified…with a combined prevalence of only 10%.” (1)

For those who may not know the botanical names, that’sMonterey pine and Monterey cypress that are the runners-up to eucalypts as the most popular trees for over-wintering monarchs.  Although monarchs roost in those trees in their native range on the Monterey peninsula, they also use those species outside their native range.  Unfortunately, just as the eucalyptus is a target of native plant advocates who demand their destruction because they are not native, bothMonterey pine and Monterey cypress are targeted for destruction outside their native range.  For example, both Monterey pine and Monterey cypress will be eradicated from hundreds of acres of public land if the FEMA grants are funded in the East Bay.  This is just 150 miles away from where those trees are native and there is fossil evidence that they existed in the East Bay in the distant past.  In other words, most of the trees used by monarchs for their winter homes are in jeopardy of being destroyed by the native plant movement.

Another nativist myth BUSTED!

One of the reasons why we are telling this story is that it is a tidy little example of the justifications fabricated by native plant advocates to support their destructive agenda.  In the case of the monarch, native plant advocates claim that prior to the arrival of Europeans, before eucalypts were planted and Monterey pines and cypresses were planted outside their native range, the monarch used native trees for their over-wintering habitat.  The “assessment form” used by the California Invasive Plant Council to classify Blue Gum eucalyptus as invasive says,  “[The Blue Gum] provides roost sites for migratory monarch butterflies…ecological niches for butterflies and raptors probably formerly filled by native plant species.”  No evidence is provided in support of that statement.  We have also read that claim in comments of native plant advocates on internet articles in response to those who defend eucalypts because they are needed by monarchs.

Like many of the “cover stories” of native plant advocates, this is just not true.  A search of the scientific literature about monarchs enables us to bust this particular myth to smithereens.  It would be simple enough for native plant advocates to look at the evidence before spinning their tales, but it is apparently easier to make it up, especially when they are rarely questioned.  Million Trees exists to fill this informational void.

The historical record of the western migration of monarchs

The earliest record of over-wintering monarchs in California is from 1864, when monarchs were observed over-wintering in Monterey pines in their native range.  Richard Vane-Wright, the scientist who reports this record, explains why he believes it is probably the first incidence of over-wintering monarchs in California:

“’Previous to that, no mention has been found of this interesting phenomenon…The early Spanish chronicles and traditions make no mention of it, although Monterey, a scant three miles distant, was gay with life when the last century came in…even David Douglas, the world famed botanist, and the keenest-eyes of all the strangers who came [to California] is silent regarding it.’…Douglas, the indefatigable fir tree collector, appears to have made no mention of the phenomenon in 1830-1832, despite spending two winters at Monterey.” (2)

Vane-Wright believes the eastern monarch migration to Mexico also began around the same time.  His theory is that the agricultural practices of early settlers, which cleared trees, created a population explosion of the milkweed that is the host plant of monarchs.  More milkweeds resulted in more monarchs and monarchs began to migrate in response to population pressure, he believes.  He calls this the “Columbus Hypothesis.”  (2)

Biological facts explain why monarchs choose these species of trees

Aside from the historical record, the biology of monarchs and the physical characteristics of the trees in which they over-winter explain why these species of trees are required by the over-wintering monarch.  During the late fall and winter, monarchs enter a dormant phase called diapause.  They continue to need nectar and moisture during that period, but they are not very active, so these resources must be close by.  Although they migrate to the coast from Mendocino to Mexico, they are most abundant around the mid-point of that range, where temperatures and rainfall are moderate.  Most of the approximately 250 roosting sites are within 2.4 kilometers of the ocean, so wind protection is important for them while they are roosting.  All of these factors predict the ideal conditions provided by eucalyptus trees:

  • Monarchs need tall trees (of at least 60 feet) because they roost in the intermediate level of the canopy where wind protection is greatest (3)
  • The forest must be dense enough to provide wind protection,
  • The tree canopy must be open so that the roosting monarchs receive filtered sunlight to keep their bodies warm enough.
  • The monarchs need enough moisture for hydration, but not so much that they are soaked and lose their body heat.  So, dew and/or fog provide the ideal amount of moisture.  (1 & 4)

All of these requirements for the monarch’s winter roost point to their dependence on eucalyptus, pines and cypress.  The trees that are native to the narrow strip of the coast of California do not meet these criteria.  They are not tall enough and they do not grow that close to the ocean because they do not tolerate wind.  The native vegetation of that narrow strip of California coast is predominately dune scrub and coastal grassland prairie.  And these are the vegetation types that the ecological “restorations” in the Bay Area are trying to re-create.  These vegetation types will not be suitable habitat for over-wintering monarchs.  Furhtermore, plans to drastically thin eucalyptus forests on hundreds of acres of the East Bay Regional Park District will render those habitats useless for over-wintering monarchs.

In addition to the physical properties of eucalyptus, the monarch benefits from the fact that it is flowering from about December to May, while the monarch is roosting in the tree.  The flowers of eucalyptus contain a copious amount of nectar which is also important to the honeybee because it is flowering at a time when there are few other sources of nectar.  One study reported observing monarchs feeding on the flowers of Eucalyptus globulus. (5)

Risky Business

We have mixed feelings about reporting this research about monarchs to our readers because there is some risk to the monarchs in doing so.  The evidence suggests that monarchs did not over-winter in California prior to 1864, after the magical date that nativists have selected to freeze-frame California’s landscape to their nativist ideal.  Here in the San Francisco Bay Area, this magical date is 1769, when the expedition of Portola laid eyes on the San Francisco Bay.  Will nativists declare the monarch an alien invader to be eradicated along with the hundreds of plants and animals they claim “don’t belong here?”  This may seem a far-fetched conjecture, but keep in mind that the European honeybee is being eradicated in some “restorations” because it is not native.  The honeybee is essential to the survival of American agriculture, yet its existence is threatened by the radical agenda of the native plant movement.

That’s the risk we take in reporting this evidence because we hope that it helps our readers to understand the absurdity of the nativist agenda.


(1)    Dennis Frey and Andrew Schaffner, “Spatial and Temporal Pattern of Monarch Overwintering Abundance in Western North America,” in The Monarch Butterfly Biology and Conservation, Cornell University Press, 2004.

(2)    Richard Vane-Wright, “The Columbus Hypothesis:  An Explanation for the Dramatic 19thCentury Range Expansion of the Monarch Butterfly,” in Biology and Conservation of the Monarch Butterfly, Natural History Museum of Los Angeles County, 1993.

(3)    Andres Kleiman and Miguel Franco, “Don’t See the Forest for the Butterflies:  The Need for Understanding Forest Dynamics at Monarch Overwintering Sites,” in The Monarch Butterfly Biology and Conservation, Cornell University Press, 2004.

(4)    Kingston Leong, et. al., “Analysis of the Pattern of Distribution and Abundance of Monarch Overwintering Sites along the California Coastline.” in The Monarch Butterfly Biology and Conservation, Cornell University Press, 2004.

(5)    Susan Chaplin and Patrick Wells, “Energy reserves and metabolic expenditures of monarch butterflies overwintering in southern California,” Ecological Entomology, 7:249-256, 1982

Glen Canyon Park: Six Months after Tree Destruction

Note: This article is re-published from SFGlenCanyon.Net

It’s been over six months since the trees were felled between Elk Rd and the Glen Canyon Rec Center.  Here’s what it looks like now.


The destruction part took no time at all: An avenue of majestic century-old trees, a hillside habitat for birds and animals – including insect-eating bats –  a wild bee-colony,  Those were all gone in days.

The construction part is harder.

Eucalyptus Tree Hosts a Flicker Family

Note: All these photographs are by wild-life photographer Janet Kessler.

In San Francisco’s Presidio, there’s an old, rather dilapidated eucalyptus tree. The main trunk is broken off  and ragged shafts stick in the air. Though it’s still alive, you might say that it’s ‘in decline.’

Just another eucalyptus tree 'in decline' - Janet Kessler

But this eucalyptus tree holds new life. A red-shafted flicker – a kind of woodpecker – has excavated a nest-hole.

The eucalyptus-tree nest hole of the red-shafted flicker - San Francisco. Janet Kessler

In it, there are three or four chicks.

Red-shafted flicker family in eucalyptus tree nest - San Francisco - Janet Kessler

Ever wondered how woodpeckers get insects out of their holes? Look at this tongue!

red-shafted flicker sticks out its tongue - Janet Kessler

They’re growing big, and soon they’ll move along.

Red-shafted flicker parent and chick on a eucalyptus tree - San Francisco - Janet Kessler

Then this hollow in the tree may host another family – bluebirds, maybe, or owls or swallows or chickadees or even bees.  It’s a feature of the ecosystem – and a strong argument for leaving in place trees that aren’t actually hazardous, even if they are apparently in decline or even dead. Even if they’re non-native eucalyptus, sheltering native flickers.

Birds, Bees, and “Natural Areas”

One of the concerns we have with the way our wild lands are being managed is the disrespect for habitat. Many of those who support these actions – felling ‘non-native’ eucalyptus trees, removal of trees that are dead or dying even if  they’re not hazardous, stripping away ivy and understory vegetation – don’t actually realize the impacts on the wildlife that call those habitats home. (All the photographs here are courtesy wildlife photographer Janet Kessler.)


Eucalyptus trees are hugely important as habitat trees. They provide cover and nest sites for birds as large as Great Blue Herons and Double-Crested Cormorants and hawks and Great Horned Owls – and as small as Pygmy Nuthatches.

[Edited to Add: For more pictures of heron and cormorant nests - and the story that goes with them - please see the latest article on the Coyote Yipps blog. ]

2013-05-14 great blue herons nest

Great Blue Heron Nests in Eucalyptus – Photo: Janet Kessler

2013-05-142  double-crested cormorants nest

Double-crested cormorants nest – Photo: Janet Kessler

2013-05-13 eucalyptus rookery herons cormorants

Rookery tree – Photo: Janet Kessler

Young Great Horned Owls being raised in Eucalyptus tree

Young Great Horned Owls being raised in Eucalyptus tree. Photo: Janet Kessler

Their branches and trunks provide a hunting ground for small birds like kinglets and Brown Creepers.

Brown creeper forages on eucalyptus

Brown creeper forages on eucalyptus. Photo: Janet Kessler

Since they flower in winter when few other food sources are available, they provide nectar for insects – and the birds that feed on the nectar, the insects, or both. Honeybees in particular depend on winter-flowering eucalyptus. Cavities provide nesting spot for some birds – and even bees, like Glen Canyon’s last remaining bee hive tree.

bees in euc

Beehive in eucalyptus tree (bees circled in red) – Photo: Janet Kessler


Dead or dying trees – of every species – are valuable habitat, for two reasons. They’re more likely to have cavities that are suitable for nesting (and are easier to excavate for woodpeckers and other cavity-building species). They also have bugs that come to feast on the decaying wood, and that’s bird-food.

2013-05-21 (2) hairy woodpecker

Hairy woodpecker in Glen Canyon Park. Photo: Janet Kessler

Unfortunately, the San Francisco Recreation and Parks Department – and now UCSF in its management of Sutro Forest – looks to remove ‘snags’ and dying trees.  They’ve been removed in Glen Canyon Park, and in Golden Gate Park, and this fall, massive removals could start in Sutro Forest.

2013-05-21 hairy woodpecker

Glen Canyon Park, Hairy Woodpecker. Photo: Janet Kessler

If that happens, it will have a negative impact on all the woodpeckers and cavity-nesting species of birds and even bats. It’s extremely important to leave these ‘in-decline’ trees as habitat, unless they are actually hazards.


Smaller birds and animals in particular need the cover provided by ivy and understory plants to hide from predators – and to nest.

Here’s a picture of a tiny Bewick’s Wren outside its Glen Canyon nest, taken in 2012. The tree it’s nesting in is so ivy-covered you can’t actually see it. The nest is completely hidden.

2012-04-11 bewick's wren nesting

Bewick’s wren outside nest. Photo: Janet Kessler

Here’s the same tree this year. The ivy is gone, the understory mowed down. Is the wren coming back? Not too likely.

2013-05-19 no nesting spot for wren

This year there’s no nesting spot for the wren. Photo: Janet Kessler

Spinning the Bee-Tree Fiasco

We received this letter from Scott Mattoon, a bee advocate who is concerned not just by the killing of the bee tree in Glen Canyon Park’s Natural Areas, but by the reaction of San Francisco Recreation and Parks. If, like us,  you were expecting a heartfelt apology – as when the first bee-hive was killed – it didn’t happen. Instead, there’s spin. We publish the letter below with his permission.


Rec & Park recently posted an update to their website on the Glen Canyon renovation that I found rather disturbing.

[That link is HERE: Glen Canyon Park Renovation: Progress update – work proceeding…]

In reference to the plan to preserve the colony of honeybees living in the trunk of a ponderosa pine originally designated for removal, Rec & Park claimed that “the bees … have been preserved“.  That’s an interesting spin on what I would describe as a fiasco and careless blunder.  The vast majority of that colony died, and with it the likelihood of propagation this year.  Rec & Park’s contractor, DeKay, mistakenly cut the trunk at a height of 5 feet, despite an agreement  with Rec & Park to cut it at 20 feet.  They cut right into the top combs of the colony’s nest, and split the trunk open in the process, leaving the entire nest of this majestic old honeybee colony exposed.

red arrow on bee tree (Photo - Scott Mattoon)

If not for the perseverance, vigilance, stewardship, and expertise of two local residents, the colony would have certainly been lost completely.  In particular, I commend Karen Peteros for rescuing the queen and a small retinue of nurse bees, and hiving them in another part of the city.  We hope they will pull through.

Before the cutting began, I was impressed with Rec & Park’s willingness to work with myself and Karen to come up with a plan to save these bees.  It felt like we had a true partnership in the making, and that Rec & Park recognized the importance of preserving these bees, especially since their department had recklessly exterminated another colony of honeybees in the vicinity less than two years earlier.

[Webmaster: For a link to a report on that unfortunate event, go HERE: When the First Glen Canyon Beehive Was Killed]

It’s easy to assume that losing a colony of bees from the park will have no significant effect on the health or recreational value of the surrounds – just the flap of a butterfly’s wings.   But the loss of confidence in Rec & Park’s ability to effectively manage contractors, to coordinate with residents, and to accept responsibility for mistakes is significant for me and others who followed this story.  It was an opportunity for collaboration and for preservation of a natural resource squandered.


exposed hive with bees (Photo- Scott Mattoon)

Glen Canyon: Nesting Season, Habitat Destruction, and Pesticide

The nesting season is in full swing, now, and pictures of baby owls and other baby wildlife are beginning to hit the Internet. Glen Canyon is – or has been – an exceptionally good nesting area, with many kinds of habitat, undisturbed thickets for protected breeding spots, and easy access to food and water.

But the Natural Areas Program doesn’t appear to have registered this. We reported on this last year, and they’re doing it again – breaking down thickets and spraying pesticides, despite the obvious risk of disturbing birds and other wildlife. An observer wrote us: “… a group of four individuals with picks and axes are at it in the mid section of the park.”

Spraying pesticides in Glen Canyon March 2013

“This is way back in the park which we had hoped to keep wild. They’ve already removed much of the understory and now they are poisoning. “

It’s no use to ask the staff to look out for nests. Birds, especially small ones, hide their nests as thoroughly as they can. They’re difficult to find even if you know what to look for. Some are very tiny: a hummingbird’s nest is the size of a quarter. Even with the best will in the world, these workers would find it impossible to guard against disturbing or destroying nests or dens.

2013-03-14 (2)

What is it?  A tank mix of Aquamaster and Milestone, apparently. Aquamaster is glyphosate, the same stuff that goes in Roundup. And Milestone is the pesticide that doesn’t go away (and is therefore banned in New York, which fears it will get into its waterways). The Natural Areas Program has steadily increased its use of pesticides since 2009, and Milestone use has increased particularly sharply in 2012.  It looks like 2013 is off to a good start.  (For more information about the pesticide applications and the pesticides themselves, read SF’s Natural Areas Program Uses Even More Pesticides.)

Glen Canyon Park Loses Another Bee Tree

Back in October of 2011, SF RPD destroyed a bee tree in Glen Canyon Park.  Now the second one’s gone too, presumably the victim of another mistake.


The first bee hive was mistakenly killed when a park employee mistook the nest – which was registered with the feral bee project – for a hornet’s nest. It was destroyed and sealed before a proper identification was made. SF RPD apologized. That story is HERE.

A lone bee returns to a devastated nest

So what happened this time?


One of the trees scheduled for felling was one of the remaining bee trees, on the slope above Alms Rd. SF RPD agreed to preserve the nest by leaving a 20-foot stump. Instead, it was chopped off at 5 feet, opening up the cavity in which the bees nested.

They’re gone.

[That story, with more pictures including a close-up of the exposed hive, is HERE.]

The former bee tree

Glen Park Trees, Day 4: Only Two Await Their Fate

It’s nearly over. The magnificent tall eucalyptus, over a century old, are nearly gone. This video is entitled “Remembrance” and set to some very appropriate music.

Look elsewhere, birds, bats, bees; look elsewhere, children who played among these trees and bushes; look elsewhere, those whose childhood memories include this lane and these trees.

Bats About Glen Canyon Park

2012-02-23 at 18-08-20_1 batBats are insect-eating machines. According to the USGS, “Bats normally eat about half their weight in flying insects each night.”  So even for those who don’t find these night-flying mammals charming, it’s good to know there are bats among us.

San Francisco has at least four species of bats, all of which eat insects. According to research by Jennifer Krauel, which involved recording bat sounds to determine which species they were, Mexican Free-tailed bats are the most common. Parks with water – like Glen Canyon – also have Yuma Myotis bats. The other two species she found (more rarely) were Western Red Bats, and Little Brown Bats, and she found them in just a couple of places.

2012-04-07 at 19-41-44 batHer research indicated that “amount of forest edge and distance to water were the factors best explaining species richness and foraging activity.”  It also showed that bats in San Francisco remain active through the winter and don’t hibernate or move elsewhere.

If you’re interested in reading her paper, it’s here as a PDF: Jennifer Krauel thesis on bats in SF


Glen Canyon’s bats are often visible at dusk. They’re most evident in the Fall, though they’ve been seen at other times of the year.  (The pictures above are from February and April, those below from October.)

Here’s a note on bat-viewing from one visitor to Glen Canyon.

“It was late in the afternoon, and late in October. We were standing around the entrance to the park on Alms Rd.  As dusk fell, bats emerged from the tall eucalyptus trees. Quite suddenly they were  in the air right above us. I pulled out my camera, which is not really good in poor light but I tried to take some pictures anyway. Here’s one:

bats 1

“They’re difficult to spot in the picture, but all those black smudges are bats that were moving too fast for my pocket-camera. Here’s the same picture, cropped, with the bats circled in yellow:

bats 1a

“They dispersed over the canyon. Here’s another picture from a few minutes later (and the one below it shows where the bats are).

bats 2

bats 2a

“It was fantastic. I haven’t seen this many bats anywhere in San Francisco.”


We did a little research, and found a Stanford report that emphasized the importance of large trees to a particular species of bats, Yuma Myotis… bats that Krauel’s research had actually found in Glen Canyon Park. 

“Yuma bats that forage in the preserve travel several miles to roost in large trees in Portola Valley and Woodside, suburban communities on the San Francisco Peninsula. The average diameter of the bats’ chosen trees is about a yard across — more than three times wider than the average tree in those areas.”

(The link to the abstract of the actual Stanford research paper is HERE.)

That’s the size of the big eucalyptus trees in Glen Canyon Park – including those that SFRPD wants to chop down.


Bats are an important part of an eco-system, and fill a role few other creatures do: They hunt night-flying insects like mosquitoes that birds don’t catch because they’re sleeping. This is especially important now as West Nile virus, a mosquito-borne disease, has been spreading.

Having bats in a landscape contributes to its bio-diversity. All species of bats are protected in California.

(Some people are concerned that bats carry rabies – and it’s true no one should handle bats, especially grounded bats that may be sick, with their bare hands. But according to the California Department of Fish and Wildlife, less than 1% of bats are infected. [Click HERE to see their note.]  The risk of getting rabies from a bat is less than the risk of being struck by lightning.)


We’re concerned about the impact of the planned tree removals on Glen Canyon’s bats.

  • All species of bats are protected, and removing the trees will impact their habitat by reducing the number of safe roosting spots, especially for Yuma Myotis bats that need both large trees and nearness to water.
  • The contractor will be chopping down the trees in the daytime. Bats roosting there are likely to be killed – if not in the process of the tree-felling, by being forced to fly blinded and confused in the daytime and fall prey to hawks, crows and ravens.

How is SF RPD going to ensure the protection of these bats?

And in what ways will felling large trees near the stream alter the ecology of the canyon?

Red Shouldered Hawk in a Natural Area

Hawks need tall trees for roosting, watching, and nesting. This one is watching from a non-native cypress tree. (Photo credit: Janet Kessler)


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