Toxic Roundup Herbicide, Fruiting Blackberry

The SFRPD’ Natural Resources Department (NRD) is spraying toxic herbicides on Golden Gate Heights park. The pesticides being used are Roundup (glyphosate) and Polaris (imazapyr). Someone recently saw this notice:

Sign indicating pesticide spraying Golden Gate Heights, San Francisco, Sept 2021

On the next visit, the sign indicated that the spraying had been completed on September 2, 2021.

Toxic herbicide notice - imazapyr and glyphosate - Golden Gate Heights San Francisco CA, showing spraying was completed.What’s really bad about this is that one of the target plants is blackberry. Now, while it’s fruiting season.

Blackberry bushes with ripe and unripe fruit


Back in 2017, we caught another such instance, at that time on Mount Davidson. We wrote to the Commission for the Environment in protest, and we published an article here with the details: Pesticides on Blackberry in the Fruiting Season

Here’s what we wrote then: “It’s the time of the year when the blackberry bushes bear fruit, to the delight of children and the public in general (and not a few animals and birds)…. NRD seems willing to go by the letter of the rules, not the spirit of it. Blackberry should not be treated with persistent herbicides at all, especially not in the fruiting season. It’s going to affect children, wildlife, and anyone who loves picking the berries in season… most parkgoers.

At the time, they used only Tier II herbicides. (SF’s Department of the Environment has a three-tier rating system for herbicides: Tier III, Least Hazardous; Tier II, More Hazardous; Tier I, Most Hazardous.) This time, according to the signs, they have used both imazapyr, which is Tier II and Roundup, which is Tier I.


In 2016, the SF Department of the Environment engaged in a lengthy process of trying to improve its restrictions on  some of the most problematic use of pesticides in our parks. (You can read the entire compliance guidelines here as a PDF. It’s from the SF Environment website.  sfe_th_ipm_compliance_checklist – Copy )

Among them, they developed these restrictions:

✓ A written recommendation from a licensed Agricultural Pest Control Advisor (PCA) is required for any pesticide use. Departments that do not have PCAs on staff should contact the SF Environment IPM Manager.

✓ Only pesticides on the current SF Reduced Risk Pesticide List may be used. Usage must fall within the “limitations” listed for each product, along with label requirements.

✓ ‘Most hazardous’ (Tier I) herbicides have special limitations:

  • Use is prohibited for purely cosmetic purposes.
  • Use is prohibited within 15 feet of designated paths. If a park map exists, designated paths are those found on the maps. Otherwise, designated paths are those actively maintained by staff.
  • Use is prohibited within 15 feet of schools, preschools, playgrounds, or other areas frequented by children.
  • Use on blackberry bushes is prohibited when fruit are present 
  • If within the City limits, use requires onsite supervision by a licensed person (PCA, QAL/QAC) o No broadcast spraying with a boom is permitted except for golf courses (targeted spraying only)
  • Certain pesticide use is restricted in designated Red-Legged Frog habitat, which includes Golden Gate Park, Lake Merced, and several other areas in San Mateo and Alameda County.

Clearly, NRD doesn’t care about the preferences of park-goers, who enjoy picking these berries, or it wouldn’t be trying to spray them in the fruiting season.

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We Need to Reduce Toxic Herbicide Use in San Francisco

This note is from Anastasia Glikshtern, an officer of San Francisco Forest Alliance and a long-time San Franciscan.

Why We Need the San Francisco Toxic Herbicides Reduction Act

Most San Francisco residents do not know that the city routinely uses high-toxicity herbicides in parks and on watersheds such as Hetch Hetchy, Crystal Springs, and Alameda.

I was the same. Since 1991 I’d lived less than half a block from the Rockdale entrance to the Mt. Davidson Park and for 9 years had no idea that SF Recreation and Parks Department (SFRPD) regularly uses toxic herbicides in the park.

At the end of the year 2000 I got a dog. The entrance to Mt. Davidson was so close, Glen Canyon on my way to the Alemany Farmers Market on Saturdays. The dog needed walking. We started walking regularly on Mt. Davidson and in Glen Canyon.

I started seeing the signs – “NOTICE Pesticide Application” – regularly.
The chemical names on the notices were not yet familiar to me – except for Roundup.

At a weeding workshop by SLUG at the San Francisco Garden for the Environment in 1992, the instructor was asked for advice on using Roundup on some difficult-to-eliminate plant. Her answer: “Never even think about using this poison”. She distributed a Glyphosate/Roundup fact sheet – quite a damning one.

When I first called IPM (Integrated Pest Management – the phone number is on the notices) to complain about the spraying, I was told that Roundup is very safe and, because of the way it works, it doesn’t go anywhere.

Today it is everywhere, and it has never been safe.

• In March of 2015 the World Health Organization’s International Agency for Research on Cancer classified glyphosate (active ingredient of Roundup) as a “probable carcinogen”.
• In July of 2017 glyphosate was added to California’s Proposition 65 list (chemicals that cause cancer or reproductive effects).
• In August 2018, in DeWayne Lee Johnson v. Monsanto Company, a San Francisco jury awarded $289.2 million in damages to a former Benicia School District groundskeeper with terminal non-Hodgkin’s Lymphoma.
• In March 2019, a jury in a federal court in San Francisco unanimously ordered Monsanto to pay roughly $80 million in damages for failing to warn plaintiff Edwin Hardeman of the cancer risks of Roundup herbicide.
• In May 2019, after less than two days of deliberations, a California jury found Monsanto guilty and ordered it to pay over $2 billion in punitive and compensatory damages to a married couple who both developed non-Hodgkin’s Lymphoma they say was caused by their many years of using Roundup products.
• The 4th trial started in San Bernardino with opening statements on August 5th 2021:
• More than 100,000 people have filed lawsuits against Monsanto/Bayer claiming that Roundup – and the company lying about its safety – caused their lymphomas.

In 2015, the Annual Public Hearing Regarding Pest Management Activities on City Properties was packed. Most of the attendees were speaking against herbicides in parks. You can read about it here : (

The SFRPD herbicide use noticeably decreased in 2016. Then it started going up again in the following years. In 2020 it’s the highest we have records for. It is particularly bad in the SFRPD’s Natural Resource Division (NRD, formerly NAP).

The IPM boasts of huge percentage reductions in some category of herbicides (Tier I toxicity) or in particular herbicide/active ingredient. (SF Department of the Environment uses a three-tier classification for pesticides, where Tier III is Least Hazardous, Tier II is More Hazardous, and Tier I is Most Hazardous.)

However, it is good to keep in mind that the pesticides are moved from one tier to another (Roundup, which is currently Tier I, was Tier II before 2015), or the same active ingredient suddenly becomes “much safer” with a new inactive ingredient (Vastlan – new for SF – has the same active ingredient as Garlon, but is assigned to Tier II instead of Tier I). You can read about it here.

When asked at one of the Commission on the Environment meetings, to commit to reducing herbicide use, the IPM’s answer was: it is impossible, because they might need any and each of the herbicides on the “Reduced Risk” Pesticide List, and the quantity needed is impossible to predict.

When San Francisco Forest Alliance’s representative spoke about the risks of pesticide use at the 2019 Commission on the Environment meeting she was rebuked by a Commissioner, who said the matter should be left to the experts. If all is to be left to “experts” – why bother with public hearings – or, indeed, an Environment Commission?

The attendance at the pesticide hearings and the Commission on the Environment meetings regarding pesticides have decreased to almost zero, even before Covid restrictions. When writing a letter on the subject, I always think “Why bother? Why waste my time?”

I really want the city to stop spraying Roundup (glyphosate) and other toxic herbicide products. Though Roundup has been the focus recently, that’s only because it is so well-known, well-researched, and widely used. Other herbicides may well be as dangerous (and we know for sure that some are).

Other neighbors of Mt. Davidson, Glen Canyon, Bernal Hill, Bay View Hill, McLaren, Marietta Rocky Outcrop, Pine Lake, Twin Peaks, and many other parks, who walk there frequently, also regularly see notices of pesticide applications, or even the actual sprayings. These are neighborhood parks where families go with children and pets.

Unless there’s a law, there’s no way to reduce the use of toxic herbicides in our parks and watersheds. It just will not happen. Going to the voters is the only way to get it.

The ballot proposition, San Francisco Toxic Herbicides Reduction Act, is ready.
The website,, has a legal text of the measure among other things. The law would ban the use of all herbicides, except organic and EPA minimum risk, on city property, excluding only SFO’s airfields, and Harding Park Golf Course which is under PGA contract.

It can be done! The claim that managing land without herbicides is impossible isn’t true:
• France banned all use of synthetic pesticides in public spaces in 2017, and banned garden use starting in 2019.
• There is a petition to follow the French example and ban all pesticides in UK gardens and urban areas.
• In Canada 170 cities and towns are pesticide free.
• Right next to us, in Marin, the Marin Municipal Water District has been herbicide free since 2005 (which was formally incorporated in law in 2015). Most towns in Marin County don’t use herbicides at all, and in the Town of Fairfax, a neighbor notification is required prior to the use of pesticides on private property.
• Right next to us, the City of Richmond had completely banned use of herbicides in weed abatement activities by the city or its contractors in 2016.
• In 2000 the Arcata City Council banned the use of pesticides on all properties owned or managed by the city, by unanimous vote. (The city hadn’t actually used them since 1986.)
• Non-toxic Irvine, started by parents of kids with cancers, convinced the city of Irvine to switch from regular use of herbicides and toxic fertilizers to eliminating all of them under all circumstances and adopting a completely organic pest-management program. The new program also costs less (even with initial investments in soil augmentation included), and water use was reduced by 30%.

Using herbicides is expensive. Pesticides are expensive. They need to be stored in certain way. The applicators need to be certified and supervised. Warning posting is required. Reporting is required.

In 1986 Arcata’s task force cost analysis compared the use of pesticide application to manual vegetation removal and found that increased labor costs were balanced by decreased costs of purchasing, applying, reporting and storing of the pesticides. According to Dan Diemer, Arcata’s Park Superintendent, “From a management perspective it’s actually easier to not use pesticides. The amount of training and paperwork that is required for pesticide use is intense.”

The city of Irvine found that financial benefits come along with ecological and health benefits from eliminating toxic pesticides from landscaping routines.

The parks of San Francisco belong to the people of San Francisco. They have paid to acquire those properties for public use in the past and we are now paying the salaries of those who are managing the parks. The management must not include poisoning of the environment.

[ETA: SFO’s Airfields also excluded from the ballot proposition.]

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Nearly 50 Trees on San Francisco’s Market Street Threatened

Here we go again.

San Francisco’s cutting down more trees, as though its paltry tree cover – less than any other major city – needed further depleting. This time, 49 trees on Market Street are planned to be felled to make way for fancy new BART station entrances.

BART entrance with trees – Market St San Francisco. (Copyright Lance Carnes)

These trees are part of San Francisco’s green infrastructure that the city should strive to protect, not heedlessly destroy. And they’re habitat.


Aside from providing nest sites for birds, these trees are the nursery tree of the beautiful butterfly, the Western Tiger Swallowtail. As early as nine years ago, when the Market Street trees were threatened by an ill-conceived street plan, these butterflies were documented as breeding in the London Plane trees (sycamore) that line both sides of market street. (You can read about that here with photos of a just-born butterfly.) These are the famous “Tigers of Market Street” that have been written about in the Smithsonian Magazine, in National Geographic’s Field Notes, in Bay Nature. This little urban ecosystem is a San Francisco treasure – a street that to a bug or bird’s eye, resembles a tree-lined river canyon. Cutting down 50 of these trees is a terrible idea.

(Though the public hearing is over, please do write to SFDPW, your supervisor and to BART about these trees. The relevant Order numbers are: 204929, 204930, 204931, 204932, 204933, 204934, 204935, 204936, 204937, 204938, 204939, 204940, 204941, 204942, 204943)


Trees are a vital part of urban infrastructure.

  • Trees fight pollution, especially particulate pollution that is dangerous to human lungs.
  • Trees improve air quality
  • Trees are good for physical and psychological health; to get the same benefit as living on a tree-lined street, you would have to be ten years younger.
  • Trees provide habitat for wildlife, especially birds and butterflies.
  • Trees help regulate water by absorbing it into their roots and gradually releasing it through their leaves.
  • Trees reduce crime and improve business.

For a detailed list of benefits, read Twenty Reasons Why Urban Trees are Important to Us All

A group that is trying to save these trees estimates their value at $500,000. In fact, given the infrastructure benefits of trees, that is an underestimate. It’s like putting a value on air: It’s free until you don’t have it, and then it’s infinitely valuable.

San Francisco has too few trees.

Unfortunately, every project seems to start with destroying trees – and neighbors never know about it until it’s a done deal and the trees have 30-days-to-death notices on them. Then they object… but the odds are against them. Though they sometimes succeed in saving the trees, more often it’s too late.  Meanwhile, the City seems to be entirely accepting of tree destruction for any and all reasons.

As of 2013, San Francisco had a tree canopy of only 13.7%, the lowest of any major city, and nearly half the appropriate canopy cover of 25%.  Given that this data is now 8 years old, in an administrative environment that favors cutting down trees over saving them, we expect the current situation is worse.

(From SF Data: In preparation for the San Francisco Urban Forest Plan (2013), the Planning Department performed an Urban Tree Canopy (UTC) Analysis using aerial imagery and additional data sets to determine a canopy estimate for the City & County of San Francisco. This analysis estimated San Francisco’s tree canopy at 13.7%  )

Graph showing urban tree canopy cover in major US cities

San Francisco Has the Least Canopy Cover of any Major US City

This is an embarrassment for a “green” city, quite aside from the ecological, environmental and health reasons for saving our trees. Unfortunately, between Nativists, developers, and project managers, there seems to be a wave of tree cutting hitting San Francisco. We’re not augmenting our canopy, we’re shrinking it.

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Nesting in the Eucalyptus

Of course it’s no surprise to any of our readers that eucalyptus stands are an excellent resource for nesting birds. A colony of double-crested cormorants nests (or did nest) near Lake Merced; great horned owls nest in eucalyptus trees in Glen Canyon and Golden Gate Park; and flickers nest in an old eucalyptus tree in the Presidio.
But we loved this article by Dr. Allison J. Gong, a life-long Californian, and a marine biologist, backyard beekeeper, columnist for Bay Nature Magazine, and college-level biology professor.

This article was originally published at Notes From a California Naturalist  and is republished here with permission.

(As a comment, we don’t think eucalyptus is dying of “sheer old age” because eucs in California have not reached the typical 200-400 lifespan of these trees, though we don’t know about guano! And we appreciate her question: “At which point, however, does a species cease to be considered non-native?”)


In Morro Bay, CA, there is a stand of eucalyptus trees that has been designated a natural preserve. In 1973 the Heron Rookery Natural Preserve was established to protect great blue herons (Ardea herodias) as they nested. Since then other bird species have taken to nesting in these same trees. When we were there at the end of May we saw these species with nests in the eucalyptus trees:

  • Great blue heron (Ardea herodias)
  • Double-crested cormorant (Phalacrocorax auritus)
  • Great egret (Ardea alba)
  • Snowy egret (Egretta thula)

This particular rookery is not at all removed from human activity. It is right across the street from the municipal golf course and next to a hotel, and there is a walking/biking trail that runs directly under the trees. Signs advise people to keep their voices down, but pedestrians are walking under the trees all day, dodging the rainfall of guano from above. The birds don’t seem to be bothered.

Unlike the Brandt’s cormorants (Phalacrocorax penicillatus), which nest on cliffs and rocks, the double-crested cormorants nest in trees. Birds build nests with local materials, and there is a difference in what I could see making up the nests of these two species. The Brandt’s cormorants at Natural Bridges in Santa Cruz were using seaweeds as the main building material; I could see birds flying back with algae in their beaks, and then either handing it off to a mate on the nest or tucking it into the existing structure itself. In some cases I could see the pieces of algae well enough to make a tentative ID.

Brandt's cormorants (Phalacrocorax penicillatus) nesting on rock arch at Natural Bridges 2021-05-14 © Allison J. Gong

Brandt’s cormorants (Phalacrocorax penicillatus) nesting on rock arch at Natural Bridges 2021-05-14 © Allison J. Gong

Those are the Brandt’s cormorants. The double-crested cormorants nest in the trees, as we saw at the heron rookery. Here’s a pair that have a brood of three chicks:

Double-crested cormorant (Phalacrocorax auritus) parents and trio of chicks 2021-05-23 © Allison J. Gong

Double-crested cormorant (Phalacrocorax auritus) parents and trio of chicks 2021-05-23 © Allison J. Gong

At Morro Bay, which is an estuary rather than a rocky area, the double-crested cormorants use a lot of eelgrass (Zostera marina) in their nests. Eelgrass is very abundant in the Morro Bay harbor and Estero, whereas the birds would have to fly a bit farther to gather algae. Eelgrass, being a true plant, is less slimy than the algae are, and these cormorants’ nests look much drier than the mounds of algae used by the Brandt’s cormorants up in Santa Cruz.

A short distance up the coast at San Simeon the double-crested cormorants were nesting in a smaller rookery, also in eucalyptus trees. I liked the pattern of how these four nests were situated in three-dimensional space:

Double-crested cormorants (Phalacrocorax auritus) nesting at San Simeon 2021-05-23 @ Allison J. Gong

Double-crested cormorants (Phalacrocorax auritus) nesting at San Simeon 2021-05-23 @ Allison J. Gong

Returning to goings-on at the heron rookery in Morro Bay, the herons and egrets were also raising youngsters in that stand of eucalyptus trees. Remember, this rookery is very easily visited by humans. Here’s a view of the trees, taken from the small parking area:

Heron Rookery Natural Preserve in Morro Bay, California 2021-05-23 © Allison J. Gong

Heron Rookery Natural Preserve in Morro Bay, California 2021-05-23 © Allison J. Gong

It’s difficult to photograph the nests because of all the branches obscuring the view. We were also there near mid-day, with the overhead sun making lighting conditions less than favorable for good photography. I did find one comparatively visible heron nest, containing one parent and one sullen punk-ass teenager of a chick. The nestling had started growing feathers but was still almost half fluff, clearly not ready to fly yet.

Great blue heron (Ardea herodias) nest at the Heron Rookery Natural Preserve 2021-05-23 © Allison J. Gong

Great blue heron (Ardea herodias) nest at the Heron Rookery Natural Preserve 2021-05-23 © Allison J. Gong

Both great egrets (Ardea alba) and snowy egrets (Egretta thula) nest at the heron rookery. Here’s a great egret nest with two chicks:

Great egret (Ardea alba) nest at the Heron Rookery Natural Preserve 2021-05-23 © Allison J. Gong

Great egret (Ardea alba) nest at the Heron Rookery Natural Preserve 2021-05-23 © Allison J. Gong

From what I could see, the herons and egrets don’t use any marine material at all to build their nests. One factor that determines the suitability of a potential building material is proximity—even if a certain material is fantastic in other ways, birds may not use it (or may use less of it, compared to other materials) if it costs too much energy to fetch and bring back to the nesting site. For the herons at this site, sticks are easy to come by. Another thing to consider is that herons and egrets are not marine birds. Although some populations live and nest in coastal areas, most do not. Thus it is not surprising that their nests are built from materials that are terrestrial rather than marine.

I did not see any snowy egret nests in areas where they could be photographed well. However, there were some adult snowies in their spectacular breeding plumage. There was enough of a breeze to ruffle up those long plumes that used to be harvested to decorate ladies’ hats.

Look at these beautiful birds!

Adult snowy egret (Egretta thula) in breeding plumage 2021-05-23 © Allison J. Gong

Adult snowy egret (Egretta thula) in breeding plumage 2021-05-23 © Allison J. Gong

Adult snowy egret (Egretta thula) in breeding plumage 2021-05-23 © Allison J. Gong

Adult snowy egret (Egretta thula) in breeding plumage 2021-05-23 © Allison J. Gong

For several decades now, the cormorants, herons, and egrets have been nesting in these eucalyptus trees, which brings to mind the consideration of native versus non-native species. The trees themselves, blue gum eucalyptus (Eucalyptus globulus) are non-native, having been imported to California from Australia starting in the 1870s. This introduction was encouraged by calls to replace native trees that had been cleared for fuel and building material, both of which were desperately needed during and after the Gold Rush. Since ecologists began considering the effects of non-native species in the 1980s there has been a backlash against the blue gums. Given their large size, their having been planted in groups to serve as windbreaks, and their propensity for dropping a lot of debris, they are very conspicuous, and it is easy to get all hot and bothered at how in certain places they dominate the landscape.

Great egret (Ardea alba) in flight 2021-05-23 © Allison J. Gong

Great egret (Ardea alba) in flight 2021-05-23 © Allison J. Gong

At which point, however, does a species cease to be considered non-native? Having been established in California for 150 years, what is the role of E. globulus in the ecology of the Golden State? There are many people and organizations that would like to see the blue gums eradicated, or at least their populations greatly reduced. On the other side of the argument, groups such the San Francisco Forest Alliance posit that blue gums should be treasured as heritage trees.

At the Heron Rookery, some of the eucalyptus trees are dying. One reason is sheer old age. Another is the several decades’ accumulation of bird wastes onto the soil, which is slowly killing the trees. As the blue gums die, the birds will have to find other places to nest. One of the pro-eucalyptus arguments is that many species of native birds—not just these here but other species such as red-tailed hawks, red-shouldered hawks, and a whole host of songbirds—nest in eucalyptus trees throughout the state. If the blue gums are removed, then where will these undoubtedly native birds nest? Especially if the native trees have long been gone?

Taking the long view, my guess is that the birds will figure it out. Ecological communities evolve over thousands of years. The 150 years of the eucalyptus trees’ presence in California seems like a long time, but in terms of ecological time they are merely a blink of the eye. The herons, egrets, and cormorants have been nesting at the Heron Rookery for an even shorter period of time. When this stand of blue gums is gone, due to either natural attrition or removal by humans, the birds will find another place to nest. They might not choose a place that is so easily visited and observed by people, though.

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Why Large-Scale Native Plant “Restoration” Cannot Work

This article discusses two approaches to native plant restoration. One creates jobs and provides healthy outdoor opportunities. The other poisons plants with synthetic chemicals. Neither actually works to restore native plants.
Reprinted from Conservation Sense and Nonsense with permission and minor changes.



There are chemical and non-chemical approaches to native plant restoration. Neither succeeds.  Non-chemical methods are labor-intensive, which makes them prohibitively expensive.  Chemicals are cheaper and they kill non-native plants, but they don’t restore native plants because they kill them and damage the soil. Either strategy must be repeated continuously to be maintained.

This article is the 25-year story of reaching the conclusion that neither chemical nor non-chemical approaches are capable of restoring native plants on a landscape scale.  Where do we go from here?

In 2014, the California Invasive Plant Council (Cal-IPC) conducted a survey of land managers to learn what methods they were using to control plants they considered “invasive.”  The Cal-IPC survey reported that herbicides are used by 94% of land managers and 62% use them frequently.  Glyphosate was the most frequently used herbicide by far. In 2014, no other eradication method was used more frequently than herbicides.

Pie chart showing land managers' use of pesticide to kill "invasive" plants. 72% used them Frequently or Always.r

Frequency of herbicide use by land managers in California to kill “invasive” plants. Source California Invasive Plant Council, 2014


We have learned a great deal about the dangers of herbicides since 2014. 

  • The World Health Organization has categorized the most frequently used herbicide—glyphosate—as a probable carcinogen.
  • The manufacturer of glyphosate, Monsanto-Bayer, was successfully sued by terminally ill users of glyphosate.  These product liability lawsuits resulted in multi-million dollar awards for damages. The awards were reduced on appeal but ultimately upheld.  Monsanto has agreed to pay more than $10 billion to settle close to 100,000 product liability claims.
  • The US Environmental Protection Agency has finally published its Biological Evaluation (BE) of the impact of glyphosate products (all registered formulations of glyphosate products were studied) on endangered animals (mammals, birds, amphibians, reptiles, fish, invertebrates) and plants. The BE reports that 1,676 endangered species are “likely adversely affected” by glyphosate products. That is93% of the total of 1,795 endangered species evaluated by the study. Both agricultural and non-agricultural uses of glyphosate products were evaluated by the BE. Although only endangered plants and animals were evaluated by the BE, we should assume that all other plants and animals are likewise harmed by glyphosate because the botanical and physiological functions of plants and animals are the same, whether or not they are endangered. 


San Francisco’s Recreation and Park Department has increased the use of herbicides in public parks every year since 2016.  In 2020, herbicide use increased significantly from 243 applications in 2019 to 295 applications in 2020.  SF RPD has been spraying herbicides on non-native plants for over 20 years.  They have been using hazardous herbicides on some 50 target plant species year after year. The longer they use them, the more resistance to the herbicides the plant develops.

Bar chart showing pesticide use in San Francisco's "natural areas" increased sharply from year 2016 to 2020.

Herbicides used by Natural Resource Division of San Francisco Recreation and Parks Department. Source San Francisco Forest Alliance based on public records of pesticide use

Chris Geiger, director of the integrated pest management program at the San Francisco Department of the Environment, told San Francisco Public Press that although the city has reduced its use of glyphosate outside parks, it won’t ban glyphosate because it hasn’t found a more efficient or safer alternative for controlling some weeds. He said, “In habitat management, there are certain plants you cannot remove from a natural area by hand.”

San Francisco’s IPM program recently published  “Pest Prevention by Design Guide” that illustrates the bind they are in with respect to promoting native plants while trying to reduce pesticide use.  On the one hand, the Guide promotes the use of native plants in landscape design plans by making the usual claim that “Native species are generally best suited to supporting local insect populations and ecosystems.”  On the other hand, the Guide recommends the use of “pest resistant” species that are not eaten by insects and grazing animals and are capable of outcompeting weeds.  Can’t have it both ways, folks!!

East Bay Regional Park District has made a commitment to phase out the use of glyphosate in developed areas such as parking lots, playgrounds and picnic areas.  However, EBRPD remains committed to using glyphosate and other herbicides to eradicate non-native plants on undeveloped park land. In 2020, no glyphosate was used in developed areas, but about 23 gallons of glyphosate were used to eradicate non-native plants on undeveloped park land. Twenty-one gallons of triclopyr were also used to eradicate non-native shrubs and to prevent non-native trees from resprouting after they were cut down. They continued the 15-year effort to eradicate spartina marsh grass with imazapyr. A few other selective herbicides were used on other eradication projects. (2)

In the San Francisco Bay Area, most land managers are still committed to using herbicides, particularly in so-called “natural areas,” regardless of the damage herbicides do to human health, wildlife, and native plants.  In fact, the City of Oakland is planning to begin using herbicides on 2,000 acres of public parks and open spaces for the first time to implement its vegetation management plan.  The vegetation management plan is both a fuels reduction program and a “resource protection” program, which is a euphemism for native plant “restoration.”

Given what we now know about the dangers of herbicides, why are public land managers still committed to using herbicides?  The City of Oakland explains in the EIR for its vegetation management plan why it is proposing the use of herbicides where they were prohibited in the past:

“It is estimated that if the City were to rely on hand removal and mechanical treatments in place of herbicide, it would cost the City up to 40 times more to treat these areas than under the VMP. The cost for herbicide treatments, not including any associated physical treatments, is approximately $250-$500 per acre. This reflects a range of potential vegetation conditions, vegetation types, and densities. The cost for hand removal and mechanical treatments is estimated at approximately $1,000-$4,000 per acre, using the same range of site-specific conditions.” (page 5-9)

In other words, herbicides are the preferred method of killing non-native plants because it is the cheapest method.  However, there is another reason why herbicides are preferred to non-chemical methods.  There isn’t a non-chemical method that is more effective than using herbicides.


As we should expect, new information about glyphosate has increased the public’s awareness of the dangers of pesticides.  California Invasive Plant Council has responded to the public’s growing awareness and concern about the herbicides to which they are exposed in our public parks and open spaces.  They recently published a comprehensive 300-page brochure entitled “Best Management Practices for Non-Chemical Weed Control.”  (1) Many highly qualified land managers participated in the preparation of this credible publication.  The Cal-IPC brochure is credible because it frankly admits that no method of eradication is without problems.  Irrigation and intensive planting are required for good results, but without continuing regular maintenance the results are only temporary.  Few land managers have the resources needed for success.

If you wonder why herbicides are the preferred method of eradicating non-native plants, reading Cal-IPC’s brochure about non-chemical methods will tell you why.  There is no non-chemical method that achieves better results than using herbicide. 


Herbicides are the most frequently used method of killing non-native plants, but using herbicides does NOT result in a native landscape.  “Lessons learned from invasive plant control experiments:  a systematic review and meta-analysis,” analyzed 355 studies published from 1960 to 2009 to determine which control efforts were most effective at eradicating the target plants and which method was most successful in restoring native plants. The analysis found that “More than 55% of the studies applied herbicide for invasive plant control.” Herbicides were most effective at reducing invasive plant cover, “but this was not accompanied by a substantial increase in native species,” because, “Impacts to native species can be greatest when programs involve herbicide application.”  It’s not possible to kill non-native plants without simultaneously killing native plants and damaging the soil.


Public land managers in the San Francisco Bay Area have been trying to restore native landscapes for over 25 years.  Every project begins by eradicating non-native plants, usually with herbicides.  Our public parks have been poisoned repeatedly, but native landscapes have not replaced the plants that were killed.  Meanwhile, we have learned that herbicides are dangerous to our health and animals who live in our parks.

Oyster Bay is a park in San Leandro that was built on a former garbage dump on landfill in the San Francisco Bay.  The garbage was capped with barren soil and many acres were planted with native bunch grass, as shown in these photos.  This “restoration” method is called competitive planting. The bunch grasses did not survive and the ground was quickly colonized by weeds that were then sprayed with herbicides.

The only viable alternative to using herbicides to “restore” native plants is to change the goals for native plant restorations such that herbicides won’t be required: 

  • An exclusively native landscape cannot be achieved where native plants have never existed, such as the many parks along the bay waterfront that were built on landfill.  It is an unrealistic goal.
  • Given that no effective method of achieving this unrealistic goal has been found after 25 years and the most popular method is poisoning our environment, it is time to stop trying.
  • Smaller, achievable goals must be set.  Landscape scale projects should be abandoned and replaced with small scale projects where native plants already exist.
  • Smaller areas can be managed without using herbicides because they will be affordable to manage with labor-intensive methods that are more expensive.
  • If smaller projects are more successful, they will be less controversial.  The projects are unpopular partly because they aren’t successful.

The native plant movement in the San Francisco Bay Area has bitten off more than it can chew.  Native plant advocates need to back out of their dead end and regroup with plans that are less destructive and more realistic.  As the Economist magazine said in 2015, “you can garden in a garden, but you can’t garden nature.”

(1) California Invasive Plant Council offered free video training for non-chemical methods of killing “invasive” plants on May 4, 2021, 1-5 pm.

(2) 2020 IPM Report, East Bay Regional Park District available HERE.   

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The National Park Service has an Epiphany


This article is reprinted with permission and minor edits from Conservation Sense and Nonsense.

“We were probably always wrong to think about protected places as static.” – NPS Scientist

Featured Photo from RAD Natural Resource Report.  Photo caption: “Multiple federal agencies, including the National Park Service (Bandelier National Monument), tribes, and others steward the East Jemez Mountains ecosystem of New Mexico, an ecologically transforming landscape where massive forest die-off is projected to occur more frequently in the future. Piñon pines, normally evergreen, have reddish-brown foliage in October 2002 (left). By May 2004 (right), the dead piñon pines lost all their needles, exposing gray trunks and branches. The photos were taken from the same vantage point near Los Alamos, N.M. Forest drought stress is strongly correlated with tree mortality from poor growth, bark beetle outbreaks, and high-severity fire. Credit: C. Allen, USGS” (1)

During the Trump administration federal agencies were forced to be silent about climate change.  Behind closed doors, many federal agencies were quietly preparing for the day when they would be able to begin the process of adapting to climate change.

Shortly after the 2020 presidential election, the National Park Service published a natural resources report that announced a radical departure from traditional conservation strategy that was based on an assumption that nature is static and evolution a historical event.  “Resist-Accept-Direct—A framework for the 21st century resource manager” acknowledged that the rapidly changing climate requires a new approach based on the knowledge that nature is dynamic and evolution is a current and continuous event.  Many other federal agencies participated in the preparation of the report, which implies that other federal agencies may adopt the new conservation strategy. (1)

In April 2021, the National Park Service published policy guidance for park managers based on the principles of “Resist-Accept-Direct.” The New York Times interviewed the lead author of the policy guidance, who described the new conservation strategy of the National Park Service:   “The concept of things going back to some historical fixed condition is really just no longer tenable.” 

Acadia National Park, Maine

An ecologist and the science coordinator of Acadia National Park in Maine told NY Times what this new strategy meant to him and his colleagues.  He said that as recently as 2007 protected areas like the national parks were still being thought about as static places that could be preserved forever with the right techniques. “We weren’t being trained on how to manage for change,” he said. “We were being trained on how to keep things like they were in the past.”  That means nearly everyone in his line of work was caught unprepared for the current reality. “You have a whole profession of people having to shift how we think.  We were probably always wrong to think about protected places as static.”


The federal law that established the National Park Service in 1916, defined its mission:

“…which purpose is to conserve the scenery and the natural and historic objects and the wild life therein and to provide for the enjoyment of the same in such manner and by such means as will leave them unimpaired for the enjoyment of future generations.”   H.R. 15522, An Act to establish a National Park Service, engrossed August 5, 1916 (1)  

Preservation was the original mission of the National Park Service.  In 1963, the mission of the National Park Service was radically changed by the Leopold Report, written by A. Starker Leopold, the son of Aldo Leopold.  The Leopold Report recommended a goal for national parks of maintaining historical conditions as closely as possible to those “of primitive America.”  When the Leopold Report was adopted as official policy by the National Park Service in 1967, it committed NPS to restoring park lands to pre-settlement conditions:

“Passive protection is not enough. Active management of the natural environment, plus a sensitive application of discipline in park planning, use, and development, are requirements for today’ Simultaneously, that edition of NPS policies also described the primary management task as a seemingly simple undertaking: ‘[safeguard] forests, wildlife, and natural features against direct removal, impairment, or destruction,’ and ‘[apply] ecological management techniques to neutralize the unnatural influences of man, thus permitting the natural environment to be maintained essentially by natural agents’” (1)

In 1967, the land management goals of the National Park Service became more ambitious.  The goal of “preservation” was replaced by the goal of “restoring” historic landscapes and ecosystems.  The pre-settlement landscape of 500 years ago on the East Coast and 250 years ago on the West Coast was established as the baseline landscape that NPS was committed to re-creating.  The baseline landscape was presumed to be “pristine” although it had been actively gardened by indigenous people for thousands of years.


The National Park Service calls its new land management strategy the RAD framework, an acronym that summarizes three alternative strategies:

  1. “Resist the trajectory of change, by working to maintain or restore ecosystem processes, function, structure, or composition based upon historical or acceptable current conditions.
  2. “Accept the trajectory of change, by allowing ecosystem processes, function, structure, or composition to change, without intervening to alter their trajectory.
  3. “Direct the trajectory of change, by actively shaping ecosystem processes, function, structure, or composition towards desired new conditions.” (1)

Every land management decision will choose among these alternatives based on an analysis that will begin with a climate assessment. Instead of looking to the past for guidance, the planning process will assess current conditions and project future climate conditions.  Based on that assessment, the purpose of land management plans will be adaptation to current and anticipated conditions.  Every plan will be designed for a specific place, based on specific current and anticipated conditions.  There is no one-size-fits-all plan, only a framework for devising individual plans tailored for specific parks or ecosystems within parks.

The new strategy also makes a commitment to monitor the project as plans are implemented and modify the strategy as the environment continues to change and the ecosystem responds to land management.  This is called “adaptive management” and it is essential in a rapidly changing environment. The project doesn’t end, because nature never stops changing.  It’s a process for which there is no end-stage.

It’s a challenging strategy, but one that has the potential to be less destructive than the “restoration” paradigm that always began by destroying plants and animals perceived as intruders without historical precedents.  Precisely what it will mean remains to be seen.  There will probably be pockets of resistance from those who remain committed to the “restoration” paradigm and those who are economically dependent on existing projects.  All the more reason to continue to watch what is being done and participate in whatever public process is available


There are undoubtedly hundreds, perhaps thousands of NPS projects that are based on the ambitious restoration goals of the 1963 Leopold Report.  Perhaps some were successful.  My personal knowledge of NPS projects is limited to those in the San Francisco Bay Area, my home.

Point Reyes National Seashore

An attempt to eradicate European beach grass in the Point Reyes National Seashore (PRNS) is an example of an NPS “restoration” project that should be abandoned if the new RAD framework is implemented.  The PRNS project was described by NPS staff at the 2018 conference of the California Invasive Plant Council, a source and a setting that should be considered credible by the most ardent supporters of ecological “restorations.”

About 60% of sand dunes in the Point Reyes National Seashore were covered in European beach grass when the eradication effort began in 2000.  The goal of the project was to restore native dune plants and increase the population of endangered snowy plovers that nest on bare sand.  The project began by manually pulling beach grass from 30 acres of dunes at Abbott’s Lagoon.  The grass grew back within one year, presumably because the roots of the beach grass are about 10 feet long.  Manually pulling the grass from the surface does not destroy the roots.

A new method was devised that was more successful with respect to eradicating the beach grass.  The grass and its roots were plowed up by bulldozers and buried deep in the sand.  The cost of that method was prohibitively expensive at $25,000 to $30,000 per acre and the barren sand caused other problems.  The barren dunes were mobile in the wind.  Sand blew into adjacent ranches and residential areas, causing neighbors of the park to object to the project.  The sand also encroached into areas where there were native plants, burying them.  The bare sand was eventually colonized by “secondary invaders.”  Different non-native plants replaced the beach grass because they were more competitive than the desired native plants.

In 2011, the National Park Service adopted a third strategy for converting beach grass to native dune plants.  They sprayed the beach grass with a mixture of glyphosate and imazapyr.  At $2,500 to $3,000 per acre, this eradication method was significantly cheaper than the mechanical method.  However, it resulted in different problems that prevented the establishment of native dune plants.  The poisoned thatch of dead beach grass was a physical barrier to successful seed germination and establishment of a new landscape.  Where secondary invaders were capable of penetrating the dead thatch, the resulting vegetation does not resemble native dunes.

Presentation at California Invasive Plant Council conference regarding attempt to eradicate European beach grass at Point Reyes National Seashore, November 2018

The concluding slides of the presentation of NPS staff about this project were stunning.  The slides said it is a “Restoration fallacy that killing an invader will result in native vegetation.”  My 20-plus years of watching these futile efforts confirm this reality.  However, I never expected to hear that said by someone actually engaged in this effort.  The presenter mused that such projects are like Sisyphus trying to roll a boulder up hill.

Presentation at California Invasive Plant Council conference regarding attempt to eradicate European beach grass at Point Reyes National Seashore. November 2018



The realization—or perhaps acknowledgement—that the NPS strategy of re-creating historical landscapes is unrealistic was a long time coming.  Over the 50 years that the “restoration” strategy was attempted much unnecessary damage was done.  Useful, functional landscapes were destroyed.  Healthy trees were destroyed solely because they were planted by Europeans.  Animals were killed because they were perceived to be competitors of “native” animals.  Herbicides poisoned the soil, preventing regeneration or germination of new vegetation.  Established landscapes that had not needed irrigation were replaced with native plants that required irrigation.  Stabilizing vegetation was destroyed, resulting in erosion and drifting sand. 

The National Park Service has awakened to the failure of their “restoration” strategy because of the combination of failed projects that were based on mistaken assumptions and the impacts of climate change. NPS led public land managers into the dead end of attempting to re-create historical landscapes. Now NPS will lead public land managers out of that dead end into the reality of a changed environment with a rapidly changing future. Better late than never.

  1. Schuurman, G. W., C. Hawkins Hoffman, D. N. Cole, D. J. Lawrence, J. M. Morton, D. R. Magness, A. E. Cravens, S. Covington, R. O’Malley, and N. A. Fisichelli. 2020. Resist-accept-direct (RAD)—a framework for the 21st-century natural resource manager. Natural Resource Report NPS/NRSS/CCRP/NRR—2020/ 2213. National Park Service, Fort Collins, Colorado.
  2. Planning for a Changing Climate: Climate-Smart Planning and Management in the National Park Service, NPS, April 2021.


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NRD Herbicide Use Shoots Up in 2020 in San Francisco

As we have been doing for many years now, we compiled the pesticide usage data  for San Francisco Recreation and Parks Department for 2020.  It’s getting worse year by year. Toxic herbicide use (i.e. herbicides classified as “More Hazardous” or “Most Hazardous”) has risen for the fifth year in a row.

(We exclude Harding Park – but not the other golf courses – from this analysis because it’s externally-managed under a PGA contract to be kept tournament-ready at all times.)


San Francisco’s parks are increasingly doused in toxic herbicides. In 2020, SFRPD applied herbicides 295 times, up from 243 in 2019. It’s actually the highest number since 2013, when we started compiling these data.

Of these, 201 applications were by the NRD in “Natural Areas” (this includes PUC areas managed in the same way – i.e. use of toxic herbicides against plants they dislike). The Natural Resources Department (NRD, formerly the Natural Areas Program or NAP) is the entity that in trying to bring “native” plants to more than a thousand acres of our parks, cuts down trees and restrict access to people and their pets. This is up from 144 NRD/ PUC applications in 2019. NRD, which accounts for perhaps a fourth of the land area, used nearly one half of the pesticides measured as active ingredients in fluid ounces.

NRD – and PUC lands that they are managing the same way – have sharply increased their use of triclopyr since the new pesticide Vastlan has been designated Tier II (More Hazardous) instead of Garlon, which was Tier I (Most Hazardous). In both herbicides, the active ingredient is triclopyr. They also increased their usage of other herbicides: Glyphosate, imazapyr, Milestone.


The NRD’s continually growing usage of the herbicides is a sign that this strategy is failing. They have been using hazardous chemicals on some 50 target species year after year. Theoretically, the point of  using toxic herbicides on unwanted species is to allow the desired species to replace them.  Instead, the growing usage of these chemicals shows that if anything, the situation is only made worse.

This stands to reason; “invasive” plants are successful because they are better adapted to current conditions. If they are destroyed with herbicides, the replacement is likely to be the next best adapted (thus, invasive) species. Given 50 target species, the bench is deep. This leads to a vicious cycle of hazardous herbicide use, clearly visible in the graph above.


Besides NRD, the rest of San Francisco Recreation and Parks Department also increased their usage of pesticides to the highest level since 2013. In the last couple of years, they have been using a range of herbicides all classified as Tier II. These include Axxe, Suppress, Clearcast, Lifeline and Sapphire.



San Francisco’s Department of the Environment (SFEnvironment) assigns Tier hazard ratings to the various pesticides it uses. Tier III is Least Hazardous, Tier II is More Hazardous, and Tier I is Most Hazardous.  Over the years we have been following this usage, we have seen various chemicals being moved from one Tier to another. Milestone was moved from Tier I to Tier II; Glyphosate (Roundup, Aquamaster)  from Tier II to Tier I; and triclopyr (Garlon, Garlon 4 Ultra, Turflon, Vastlan) from Tier I to Tier II (for Vastlan and Turflon). Avenger has been moved from Tier II to Tier III, which we think makes sense and makes analysis easier.

We analyze the usage of Tier I and Tier II herbicides.


SF Forest Alliance has been trying to encourage SF Environment to spearhead a reduction in herbicide use. Some years ago, it appeared that pesticide usage was declining, especially after the Roundup revelations. When we wrote our Pesticides report for 2016, the other areas of SFRPD had slashed their herbicide use; the NRD accounted for 74% of pesticide usage. By 2017, hazardous herbicide use was creeping up again.

In August 2019, we attended the annual meeting of the SF Environmental Commission about certifying the so-called Reduced Risk Pesticide List. When we spoke about the risks of pesticide use, we were rebuked by a Commissioner, who said the matter should be left to the experts.

We were dismayed. Aside from questions about why bother with public hearings – or indeed an Environment Commission – if it’s all to be left to “experts”, we were concerned the comment gave permission for much more pesticide use.

It seems the 2020 data have borne out that fear

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Respect the Nest – Wildcare Thinks of Baby Animals and Birds

Recently, Wildcare – a wild animal rehab organization – published a warning. It’s nesting season and they ask everyone to RESPECT the NEST. It’s republished here with permission.
Respect the Nest by Michael Schwab

With the help of nationally-acclaimed artist Michael Schwab, WildCare asks you to Respect the Nest this spring and summer! Learn more!

It’s almost springtime in the Bay Area, and even as you read this [post] email, birds, squirrels and other animals are nesting and preparing for their newborn and newly-hatched babies in your trees, shrubs and hedges.

First baby squirrels of 2021 Copyight Wildcare

WildCare has already admitted our first tiny, pink baby squirrels of the year!

Our Wildlife Hospital admits hundreds of injured and orphaned baby animals every spring and summer, many of them victims of tree-trimming and pruning accidents.

Michael Schwab created the Respect the Nest graphic to help us remind everyone to delay non-emergency tree-trimming and pruning until winter to avoid orphaning baby animals!

How can YOU Respect the Nest? Click to learn how to spot nesting activity and protect the wildlife in your yard.

Then join us for a free, informative Respect the Nest webinar presentation on Tuesday, March 9 [2021] at 6pm!

[The webinar is over. View the recording of the seminar on Youtube HERE.]

Attendees will learn:
– What animals may be using your trees and shrubs as a nursery… even as you read this!

– How to tell if there are active nests in your yard.

– What to do if you inadvertently cut down a nest or if you find an
injured animal.

– When it’s safe (and better for your trees) to prune and trim.

– How WildCare cares for baby animals orphaned by tree trimming.

Many people don’t know that timing our tree and shrub pruning is just one simple way we can minimize harm to wildlife.

Please Respect the Nest this spring and summer and help prevent baby animals from becoming orphaned.

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Toxic Herbicide on Mt Davidson – Triclopyr on Oxalis

In June 2020, we reported that SFRPD was using a new version of an old toxic pesticide: Vastlan, with the active ingredient Triclopyr. (The same as in Garlon, which was the single most toxic herbicide they used.)

Neighbor and videographer Ron Proctor took this video of a whole team of people applying this pesticide against oxalis, the popular pretty weed that Nativists love to hate. (The video is used here with permission.)

Click on the picture to go to the video


Oxalis is also known as sourgrass. Children like to eat it; it provides copious nectar for bees and butterflies; and wildlife eats the root bulbs, called bulbils. And lots of people like the sheer beauty of this early harbinger of spring.

See this ABC7 News report headlined Large flower bloom wows drivers on Highway 1 in Santa Cruz County

Glorious field of yellow oxalis in Santa Cruz CA

(CLICK on the picture above to go to the report.)

Toxic herbicides? Not so popular. Especially on a steep slope like this, in wind and rain conditions, the herbicide is bound to travel downhill. Whether intentionally or not, it’s going to spread through the soil.

We have for many years been asking San Francisco to stop using toxic pesticides. Only a loud public outcry is likely to have any impact.

Honeybee in oxalis flower

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More Destruction of Sutro Forest

We regret starting the year with sad news in this post from It is reprinted here with permission.

With the new revised plan for UCSF’s Parnassus Campus having been approved by the UCSF Regents – despite San Francisco’s Board of Supervisors asking for a delay so the Plan could be studied further – we expect the destruction of the forest to accelerate.

Sutro Forest Tree Destruction 2 - Medical Center Way Jan 2021 600 px

According to a UCSF report, “On Jan. 21, the Regents certified the Environmental Impact Report for Comprehensive Parnassus Heights Plan (CPHP), which amends UCSF’s 2014 Long Range Development Plan to adjust the space ceiling limit, projected campus population, and the Mount Sutro Open Space Reserve boundary.” (You can find the new Plan here (as a PDF):

Sutro Forest Tree Destruction - Bandit Intimidator Jan 2021 600px


The Space Ceiling was established in 1976 in response to neighbors’ anger at the impact of UCSF’s unrestrained growth on surrounding neighborhoods. There is more about that here. It has been expanded from 3.55 million square feet – which had been exceeded several times, with existing square footage in as of 2014 in the range of 3.84 million square feet. This Plan will raise the ceiling to 5.05 million square feet.

An article in SF Weekly in October 2019 discussed this new Plan, noting that neighbors had concerns and those were not really taken into account. Anyway, the Plan is going ahead despite any objections, since UCSF is in practice only answerable to the Regents.

The SaveSutro neighbors’ group battled for over twenty years to save the forest, which UCSF has sought to destroy for an ever-changing list of reasons since around 2001. Eventually, we were outwaited. (The picture below is the forest in 2006.)

Mount Sutro Cloud Forest 2006 copyright Tony Holiday


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Greetings of the Season, Best Wishes for 2021

It’s been a difficult year in a number of ways. The pandemic still rages, and tree-cutting continues.

Nonetheless, there have been signs of hope for all of us. So here’s a candle in the dark to represent hope. Greetings for the season, everyone,  and best wishes for 2021!

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Surprise Tree Removals for McLaren Park Native Plant Garden

San Francisco Recreation and Parks Department’s Natural Resources Division (NRD), in conjunction with Fran Martin’s Visitacion Valley Greenway group, have been planning to construct a native plant garden just south of the McLaren Park community garden along Visitacion Avenue. This seemed like a good idea until signs appeared on most of the trees in the area in late July 2020 notifying the public they were going to be cut down.

Some 14 trees were posted for cutting sometime after 20 August, 2020. There are two more trees in the middle of the area that are not posted, but are the same species as other trees slated for removal. Those will probably be removed as well. Numerous smaller saplings will also be removed, but not included in the count. Huge trees with trunks up to 4 feet in diameter will be destroyed. See the picture below.

The posting sign claims only 10 trees will be removed, but it looks like it will actually be 16 trees and numerous saplings.

Note the skillfully crafted language about the 20 replacement trees. At first glance you would think those trees would be planted in this same area, but the actual commitment is only that “trees” will be planted in this area. That is a minimum of 2. The other 18 trees could be planted in any other park at some time in the future. Given what they are cutting, they should be planting at least 32 trees.

Only one of the posted trees has an arborist’s tag, probably from the 2014 Visitacion Trail Project. During that project 100 trees were removed and no new trees were planted. It does not appear the posted trees have been surveyed (no tags) and all of the cutting is for “anticipated construction impact” and has nothing to do with “hazard rating” as suggested by the signs.

The posting was first noticed by a volunteer at the adjacent community garden. In response to his initial inquiry, San Francisco Recreation and Parks Department (SFRPD) responded:

“Please know that the mature trees in the area of the Visitacion Native Plants Garden project are not being removed without thorough consideration. The project has been included in our McLaren Trail Improvement Priorities project planning since the end of 2019, and there was unanimous community support for native plant garden development at both our Visitacion Avenue trail walk in November 2019 and our virtual community meeting in May 2020.

“Fran and I have walked the area with Rec and Park’s Head Forester, and the trees marked for removal are either hazardous at present or would be so impacted by the project construction that they would become in danger of failure.

“Ending the lives of these trees was not a light decision. It was a decision made with community input and according to Rec and Park best practices.”

Some things to point out here:

  • The claim the tree cutting decision was “made with community input” is a lie. SFRPD never disclosed the tree removals to the general public. The notes for the meetings SFRPD cites show no mention that trees would need to be removed in order to create this native plant garden. There is lots of open space already and more could be created by removing the large number of dead standing trees, fallen trees and doing some limited tree trimming. Who would have thought they needed to remove basically every non-native tree in the area?
  • What sort of “construction” is required to install a garden that would turn healthy trees into dangerous ones?
  • The NRD is claiming that basically all of the non-native trees in the area are hazardous, or would soon become hazardous due to construction impacts. Somehow, the few “native” trees would have no problem surviving the construction.
  • Apparently SFRPD’s decision was indeed “light”. The only tree evaluation was a walk through by an SFRPD capital planner, an outside proponent for the tree removals and SFRPD’s head forester. No formal evaluation of the trees was made and recorded.

The garden volunteer did not give up trying to save the trees and on August 13, 2020 SFRPD announced that it would put the tree removals on hold and that “We plan to host another community meeting where more design details and the results of a 3rd party tree assessment will be shared. We will likely schedule this meeting in the coming weeks, and I’ll let you know as soon as the date is set.”

So far there has been no further news. SFRPD will probably have their go-to arborist HortScience perform the evaluations. HortScience knows “which side their bread is buttered on”, so the evaluation may not be unbiased, but it is better than nothing.


In related history, SFRPD received an Urban Greening Grant to fund the 2014 Visitacion Trail Project. This produced the sandy trail that runs along Visitacion Avenue through the future native plant garden.

One of the main purposes of this grant program was to increase tree cover in needy locations. In the grant application, RPD promised to plant twenty 15-gallon sized trees within ¼ mile of new multi-use path. (10) Coast Live Oaks, 5 Buckeyes and 5 Garrya elliptica (Coast Silk Tassel). In their grant application, they did not disclose they were going to cut down 99 trees using the grant money. The 20 trees were never planted anywhere nearby.

These impending tree removals and dubious replacement plantings is part of a larger pattern. SFRPD is removing living trees all over the City and promising 2:1 replantings.

It is clear from freedom of information requests to RPD that:

  • Plantings are not keeping pace with removals.
  • Large scale tree removals are concentrated in areas managed by the NRD like Glen Canyon, Lake Merced and McLaren Park.
  • Meanwhile replantings are concentrated in Golden Gate Park. In SFRPD’s 2019 fiscal year, 62% of trees planted went to Golden Gate Park. SFRPD’s Fiscal Year 2019 planting records also reveal that 38% of the planted “trees” are actually shrubs that will only grow to a small fraction of the biomass of the removed trees.
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More Damage for Sutro Forest

San Francisco Forest Alliance recently responded to UCSF’s Draft Environmental Impact Report consequent on changes it plans to the 2014 Long Range Development Plan. We publish that here. We also publish with permission an article from, the website that has fought to protect the forest since 2009.

First our comments:

Dear UCSF,

We were dismayed to see the planned effects of the amended LRDP, particularly on Sutro Forest.

1) Hundreds of trees will be removed for this project.

2) With the removal of Aldea Student Housing from the space ceiling, the plan is to build taller buildings – up to 96 feet high – in an area where other buildings are restricted to 40 feet. The construction space that the process of building these structures will require is likely to destroy more trees.

3) Furthermore, an oblique reference to “a completely reconfigured and redesigned site” raises the possibility that this redesigned site may no longer be a forested area at all. It will certainly lose its charming woodsy character of wood-shingled low-rise buildings.

4) The revised plan will remove an area of Sutro Forest (near Parnassus and Edgewood). In “compensation” an area that is already de facto part of the forest would be technically included in the forest.

5) In addition to the impact on Sutro Forest – the entire redwood grove on Parnassus would be felled.

The cumulative effect of all these removals on San Francisco’s shrinking tree cover is dismal. At 13.7%, San Francisco has the smallest tree canopy cover of any major city. (This percentage was calculated in 2013, and is likely even lower now with the continuing destruction of trees in Sutro Forest and elsewhere in San Francisco.)

In these times of climate change, removing trees is an environmental hazard. Furthermore, the cumulative effect on Sutro Forest is to make it drier and less self-sustaining, and thus, riskier – especially as climate change hits California harder each year. It also sacrifices all the ecosystem services provided by the trees.

We ask that these projects be revised to protect the trees.


San Francisco Forest Alliance

And now the article:


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.

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Trees Targeted for Destruction In Golden Gate Park

One would think that in these times of climate change and San Francisco’s small and shrinking tree canopy, every effort would be made to save the trees we already have. San Francisco  already has only a 13.7% tree canopy cover, less than any other major city.

It’s not happening. San Francisco resident Wendy J Oakes was dismayed to find a number of  beautiful trees marked for destruction.

The reasons? That they might potentially fail – which is true of any tree. And, they’re an “Invasive Species.” Given that they were *planted* there, it’s pretty clear they are not invading anything. San Francisco has no native trees. It was sand dunes and scrub. These “reasons” could be used to cut down any tree at all in our city. (We will try to obtain a clearer picture of this notice.)

Edited to Add: The text of the notice reads:
Posted August 6, 2020
Notice of Tree Removal
Reasonable foreseeability for failure of whole or part tree in high target area and/or Invasive Tree Species.
Trees will not be removed before September 6, 2020 unless risk conditions warrant immediate remedy.
Further Questions can be answered by Cort Eidem Project Manager

Wendy notes that the trees are in the area of JFK Drive and Fulton, between 6th and 8th avenue – but the trees are not on JFK, Fulton, or any main walking paths. These are on small side paths that are little-used. That doesn’t sound like a high target area.


It’s not as though San Francisco is so heavily forested that it can afford to wantonly destroy its trees, especially the mature well-established ones. Its tree cover is only 13.7%, less than any major city.

Graph showing urban tree canopy cover in major US cities

San Francisco Has the Least Canopy Cover of any Major US City

In fact, even the city government admits that, in the Planning Department’s Urban Forest Plan.

Small and Shrinking Tree Canopy
San Francisco has one of the smallest tree canopies of any major U.S. city.
San Francisco was naturally a non-forested environment with fewer trees than east coast or other forested environments. Today, the City’s urban tree canopy (13.7%), measured by the amount of land covered by trees when viewed from above, is one of the smallest of any large U.S. city – less than Los Angeles (21%), Chicago (17%) and New York City (24%) – and unfortunately, it’s on the decline. New plantings are not keeping pace with tree removals and mortality, while tens of thousands of potential street tree planting spaces remain empty.”

Cutting down healthy and mature trees is certainly one of the reasons that this tree canopy is shrinking instead of growing.

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SF Rec & Parks Using a New (Old) Pesticide

One of our supporters reports the “Natural Resources Department” (NRD) of  the San Francisco Recreation and Parks Department (SFRPD) is using a new pesticide on Mt Davidson: Vastlan (from Dow). It’s being applied in a so-called “natural area” now named a “significant natural resource area.”


Only, the pesticide is not really new: the active ingredient is triclopyr. This is the same as Garlon, the highly toxic pesticide that has been listed as HIGH PRIORITY TO FIND A REPLACEMENT since at least 2009.

SF Department of the Environment – SFEnvironment – groups those pesticides that the city permits to be used on city properties into three Tiers. Tier III is least hazardous; Tier II is More Hazardous; and Tier I is Most Hazardous.

In 2019, SF Environment added Vastlan to the list of pesticides permitted for use on city-owned land, with a Tier II classification  (as compared with Tier I for Garlon 4 Ultra). It’s been listed as a Lower hazard alternative to Garlon 4 Ultra. You can see the 2019 “Reduced Risk Pesticide” list here: SFEnvironment Reduced Risk Pesticide List 092419

Though it’s Tier II, the restrictions on its use are the highest, i.e. Most limited  and the note against it says: “Use only for targeted treatments of high profile or highly invasive exotics via dabbing or injection. May use for targeted spraying only when dabbing or injection are not feasible.” This is exactly the same as for Garlon 4 Ultra, which was Tier I (and is being phased out with a “Use up existing stock” note).


But. Based on what we’ve seen with other pesticides, NRD seems to respond to the Tier rating rather than to the Use Restrictions. Already, they’ve used Vastlan on “Poison oak and other encroaching shrubs.” This is a broader use than Garlon 4 Ultra, which they had limited to oxalis.


Frankly, we are also dubious about whether Vastlan is actually safer than Garlon 4 Ultra. (The company has reduced its signal word from Danger to Warning.)
Vastlan has not been in use long enough for its risks to become apparent, and it’s always in a company’s interests to understate them if possible. The saga of the FDA and Monsanto’s Roundup suggests that they may also be understating risks.

Dow’s Label for the pesticide can be read at the link:  Vastlan label Dow
It includes the warning:

May be fatal if swallowed • Causes substantial but
temporary eye injury • Prolonged or frequently repeated skin
contact may cause allergic reactions in some individuals.
Do not get in eyes, on skin, or on clothing.


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We Still Need to Say, After All These Years: Black Lives Matter

In 2014, we first published our statement of support. It’s with something between sadness and horror that it’s essential we publish it again. In the intervening years, things have not improved for the African-American community. Because of the racism inherent in our society, they are at risk of death while doing nothing more than living normal lives. All black people, but especially black men, face violence from the very entities that should be protecting them. As we said in 2014:

black lives matterThis website normally focuses on issues relating to the environment, and more specifically to the damage being done by “nativist” thinking that destroys trees and habitat to favor “native” plants. But this topic is too important for us to ignore.

With a growing sense of outrage and concern, we’ve watched what has happened to African American adults and children – that they cannot assume they will get the same rights and consideration that others do in this country. We’re dismayed that parents need to talk to their young children, particularly their sons, about the special submissive behaviors they must adopt to avoid getting killed.

The San Francisco Forest Alliance cannot be silent on this. We stand with many other environmental organizations in our support of the movement for change.

We stand against prejudice and embedded bias, and stand with communities of color in their struggle.

Black Lives Matter.

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Pesticide Use Up in San Francisco Parks, Natural Areas – 2019

In 2019, SFRPD applied herbicides 243 times, the most since 2013. Of these, 144 applications were in “Natural Areas” (this includes PUC areas managed in the same way – i.e. use of toxic herbicides against plants they dislike). Though the Natural Areas comprise perhaps a quarter of the park land in San Francisco (not counting the PUC lands), they used nearly half the herbicides measured by volume of active ingredient.

As we have been doing for some ten years now, we obtained and compiled monthly pesticide use reports from San Francisco Recreation and Parks Department (SFRPD).  Our analysis omits Harding Park golf course, which is under contract to the PGA and must be tournament-ready at all times. We do include other golf courses, including the nearly pesticide-free Sharp Park in Pacifica. Here is our report for 2019.


The Natural Resources Department (NRD, formerly the Natural Areas Program or NAP) is the entity that in trying to bring “native” plants to more than a thousand acres of our parks, cuts down trees and restrict access to people and their pets. (For details, see this LINK.) We analyze their usage separately; they are the largest user of the most toxic (Tier I) herbicides.

The targets are a growing list of mostly non-native plants, currently more than 50 species. New to the list in 2019 are Ox tongue (Picris echioides), Velvet grass, Queen Anne’s Lace (Daucus carota), and Teasel (Dipsacus). (SF Department of the Environment – SFEnvironment – groups those pesticides that the city permits to be used on city properties into three Tiers. Tier III is least hazardous; Tier II is More Hazardous; and Tier I is Most Hazardous.)



The Tier I (Most Hazardous) chemicals used in the Natural Areas are the probable carcinogen Roundup Custom (glyphosate) and Garlon 4 Ultra (triclopyr). As indicated in the column-chart NRD Herbicide Use 2014-2019, Tier I pesticide usage fell in 2016, and has been climbing since. In 2019, both Roundup (green column) and Garlon (orange) usage rose.  In 2019, Natural areas/ NRD accounted for 98% of the Tier I herbicides used by SFRPD. Herbicides are applied in these areas both by the NRD itself, and by an outside contractor. (On Point Land Management, associated with former contractor Shelterbelt.) Unless NRD changes its objectives, it will always need herbicides – Roundup, Stalker/ Polaris, Milestone VM, Garlon 4 Ultra. If it reduces one, there’s a temptation to increase another.

Even Sharp Park in Pacifica (also managed by NRD), which had been practically exempt from herbicide use for many years, has seen pesticide use edging upward since 2017.


The continued increase in the use of Garlon (triclopyr), the most toxic herbicide that SFEnvironment permits is disturbing. Ever since we started following herbicide use in SFRPD, it’s been declared “HIGHEST PRIORITY TO FIND ALTERNATIVE.  It’s used in their perennial, pointless, and apparently escalating war on oxalis. NRD increased its use of Garlon by about 90% from 2017 to 2018, and now by a further 14% in 2019. If NRD were to call off this futile effort, it could reduce its Garlon usage to zero.

Honeybee in oxalis flower

Oxalis is a beneficial plant: It produces copious amounts of nectar, which is food for bees, butterflies, and other pollinators. Its bulbs provide food for (native!) pocket gophers and some birds. Its brilliant yellow flowers bloom early in spring, before most other flowers. Kids like to chew on its sour stems (it’s also called sourgrass) and even adults have fond memories of this plant. Other than nativist purists, most people love it for its beauty – it’s a sign of spring in San Francisco.


After reducing its pesticide use in 2016, SFRPD (excluding Harding, and excluding NRD) increased its use of herbicides each year. In 2019, it more than doubled. The main cause was the use of Clearcast herbicide in and around lakes and ponds, as well as Milestone being used in its war on Cape Marigold. The main increase has been in “Other Tier II herbicides” – mainly Clearcast and Lifeline. These are glufosinate ammonium herbicides. They also used Axxe, which may not be as bad as some others; it has an OMRI listing for organic use. The only small positive is that since 2017, SFRPD other than NRD and Harding Park, has used almost no Tier I herbicides.

SFRPD also used 482 fluid ounces of Avenger (by active ingredient), which we have omitted from the chart above.  Avenger is based on lemongrass oil, or what is called a “botanical.” It’s actually considered acceptable for organic gardening. However, it’s classified as Tier II because it can cause allergic reactions in its undiluted form.

The percentage of herbicide use by NRD has fallen (from 70% in 2018 to 46% in 2019) because usage by other SFRPD departments has increased even more rapidly than usage on NRD lands.

One of the main reasons is that they used a lot of Clearcast against water-primrose (ludwigia) and other plants – including calla lilies! – in and around San Francisco’s ponds and lakes.

In 2018, SFRPD declared war on Cape Marigold, arctotheca.  Cape Marigold (also called the Plain Treasure Flower) has bright yellow flowers that look like daisies.  It’s a ground-cover plant in the aster family, has a fairly long flowering period, and is attractive to butterflies, bees, and other pollinators. SFRPD considers it “invasive” – i.e., successful in the urban environment we currently have in San Francisco. This “war” has continued into 2019, resulting in 32 applications of Milestone. This pesticide is applied in small quantities, but is extremely persistent.

What about the other golf courses? Their pesticide use is minimal. They used 18 fluid ounces of Lontrel (clopyralid).


At a time when environmentalists are concerned about the reduction in insect populations, we should be working to preserve our “weeds.” Unlike many garden plants, which are bred for attractive flowers and often have less value to insects, these weeds flower early and abundantly. They provide food for insects of all kinds, the foundation of the web of life. But many of the target plants are beneficial to insects:  eucalyptus, the world’s largest flowering plant;  oxalis, a foundation species in our urban ecosystem; fennel, the food plant for the anise swallowtail butterfly; wild radish; wild mustard; blackberry, which provides not only food but cover for birds and animals… the list goes on.

Anise Swallowtail butterfly lays eggs on fennel

Anise Swallowtail butterfly lays eggs on fennel (c) Janet Kessler

It’s time for SFRPD and SF Environment to move to a more environment-friendly approach: Preserve the plants that wildlife needs and stop using toxic and persistent pesticides.

We would like to see SF Environment take the leadership in moving San Francisco to a policy of No Pesticides in our Parks and Watersheds.




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Answering the Smithsonian – The Flawed Logic of Native Plant Activism

In its April 2020 issue, the Smithsonian Magazine published an interview with Doug Tallamy, considered one of the fathers – or at least popularizers – of nativism. They asked Art Shapiro, who represents a broader view of the ecological role of all species, to respond. Then they gave Tallamy space to rebut his responses, but they did not give Shapiro a further chance to rebut the rebuttal. The MillionTrees blog stepped up to respond. This article is re-published with permission.


Doug Tallamy speaks…Art Shapiro responds…Million Trees fills in the gaps

Smithsonian Magazine published an interview with Professor Doug Tallamy, the entomologist who is committed to the eradication of non-native plants and most influential with native plant advocates in the United States. The Smithsonian article gives Professor Art Shapiro an inadequate opportunity to respond to Tallamy’s assertions about the superiority of native plants. Million Trees steps up to fill in the gaps in response to Tallamy.

  • The Smithsonian article says, “As a scientist, Tallamy realized his initial obligation was to prove his insight empirically. He began with the essential first step of any scientific undertaking, by applying for research grants, the first of which took until 2005 to materialize. Then followed five years of work by relays of students.”

The first study that Tallamy conducted is not mentioned in this article because it disproved his hypothesis: “Erin [Reed] compared the amount of damage sucking and chewing insects made on the ornamental plants at six suburban properties landscaped primarily with species native to the area and six properties landscaped traditionally. After two years of measurements Erin found that only a tiny percentage of leaves were damaged on either set of properties at the end of the season….Erin’s most important result, however, was that there was no statistical difference in the amount of damage on either landscape type.” (1)

  • The Smithsonian article says, “… insects tend to be specialists, feeding on and pollinating a narrow spectrum of plant life, sometimes just a single species. ‘Ninety percent of the insects that eat plants can develop and reproduce only on the plants with which they share an evolutionary history’…:”

Anise Swallowtail butterfly in non-native fennel. Courtesy

A “specialist” insect is rarely confined to using a single plant species. Mutually exclusive relationships in nature are very rare because they are usually evolutionary dead-ends. The study in which this claim about “specialization” originated, actually concluded: “More than 90 percent of all insects sampled associate with just one or two plant families.”* There are over 600 plant families and thousands of plant species within those families. Most plant families include both native and non-native plant species. An insect that uses one or two plant families, is therefore capable of using both native and non-native plant species. For example, there are 20,000 plant members of the Asteraceae family, including native sagebrush (Artemisia) and non-native African daisy. In other words, the insect that confines its diet to one family of plants is not very specialized.

  • The Smithsonian article says, But he [Tallamy] thinks this [transition of insects to non-native plants] is likely to take thousands of generations to have an impact on the food web. Shapiro maintains he has seen it occur within his own lifetime.”

There are many empirical studies that document the transition that insects make from native to non-native plants within generations. Professor Tallamy provides a few examples of such rapid transitions in his first book, Bringing Nature Home: wooly adelgids from Asia have had a devastating effect on native hemlock forests in the eastern United States; Japanese beetles introduced to the United States are eating the foliage of over 400 plant species (according to Professor Tallamy), some of which are native (according to the USDA invasive species website).

Soapberry bug on balloon vine. Scott Carroll, UC Davis

The soapberry bug made a transition from a native plant in the soapberry family in less than 100 generations over a period of 20 to 50 years. The soapberry bug-balloon vine story is especially instructive because it entailed very rapid morphological as well as behavioral change; the beak length was quickly (a few years) selected for the dimensions of the fruit of the new host. (2)

  • Doug Tallamy claims that Art Shapiro’s findings are “anecdotal.” They are not. Art Shapiro’s published study is based on nearly 40 years of data. (3)

Monachs in eucalyptus, Pacific Grove Museum

In a recent NY Times article about declining populations of monarch butterflies on the West Coast, an academic scientist explains how he used Professor Shapiro’s data set to study the decline: “The monarch’s decline is part of a larger trend among dozens of butterfly species in the West, including creatures with names like field crescents, large marbles and Nevada skippers, said Matt Forister, an insect ecologist at the University of Nevada, Reno, whose conclusions are based on a nearly 50-year set of data compiled by Art Shapiro, a researcher at the University of California, Davis. “The monarch is very clearly part of a larger decline of butterflies in the West.” Clearly, other academic entomologists do not consider Professor Shapiro’s data “anecdotal.”

The Burghardt/Tallamy study (4) does not contradict the findings of Professor Art Shapiro because Professor Shapiro is studying butterflies (not moths) in “natural areas” that have not been artificially created by choosing a limited number of plant species, as Tallamy’s study did. In other words, the adult and larvae stages of butterflies that Professor Shapiro studies have more options, and when they do they are as likely to choose a non-native plant as a native plant for both host plant and food plant. You might say, Professor Shapiro’s study occurs in the “real world” and the Burghardt/Tallamy study occurs in an artificially created world.

Dismissing observations as anecdotal is a well-worn rhetorical device. Creationists often claim that evolution cannot be proven because the theory is based on millions of observations, rather than empirically tested by experiments. Yet, virtually all scientists are firm believers in the validity of evolutionary principles.

  • Tallamy dismisses climate change as a factor in plant and animal extinctions, preferring to place the blame solely on the mere existence of non-native plants.

This claim is contradicted by a multitude of studies, such as a collection of studies recently reported by Yale E360 that concludes: “A growing number of studies show that warming temperatures are increasing mortality in creatures ranging from birds in the Mojave Desert, to mammals in Australia, to bumblebees in North America. Researchers warn that heat stress could become a major factor in future extinctions.”

Climate change is the environmental issue of our time. When the climate changes, the vegetation changes. When the vegetation changes, wildlife adapts or dies. Non-native plants are one of the consequences, not the cause of climate change or plant and animal extinctions.


*Professor Shapiro has provided a caveat to this definition of specialization of insects in a private communication, published with his permission: A couple of observations: Hardly any insects feed on entire plant families. Rather, they feed on specific lineages within those families, typically defined by secondary chemistry (which is the necessary releaser for oviposition and/or feeding behavior). The relationship was summed up symbolically by A.J.Thorsteinson half a century ago: feeding=presence of nutrients+presence of required secondary chemicals-deterrents-antifeedants-toxins. Thus the Anise Swallowtail species-group feeds on the carrot family, Apiaceae, but NOT on Apiaceae lacking the proper chemistry.But they DO feed on some Rutaceae (including Citrus) that, though unrelated, are chemically similar. That was worked out by Vincent Dethier in the 1940s and further developed by John Thompson at UC Santa Cruz. A whole slew of things require iridoid glycosides as oviposition and feeding stimulants. Most plants containing these were in the family Scrophulariaceae before DNA systematics led to its dismemberment, but one whole branch of Scrophs is chemically unsuitable. Milkweed bugs eat milkweed, but they also eat the Brassicaceous genera Erysimum and Cheiranthus, which are chemically similar to milkweeds but not to other Brassicaceae…and so on. Native vs. non-native has nothing to do with it.(emphasis added)

  1. Tallamy, Doug, “Flipping the Paradigm: Landscapes that Welcome Wildlife,” chapter in Christopher, Thomas, The New American Landscape, Timber Press, 2011
  2. Carroll, Scott P., et. al., “Genetic architecture of adaptive differentiation in evolving host races of the soapberry bug, Jadera haematoloma,” Genetica, 112-113: 257-272, 2001
  3. SD Graves and AM Shapiro, “Exotics as host plants of the California butterfly fauna,” Biological Conservation, 110 (2003) 413-433
  4. Karin Burghardt, Doug Tallamy, et. al., “Non-native plants reduce abundance, richness, and host specialization in lepidopteran communities,” Ecosphere,November 2010
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San Francisco Cutting Down its Ancient Trees – Sutro Forest/ Clarendon

This article is republished from, with permission.

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

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San Francisco Cutting Down its Ancient Trees – Lake Merced

Though San Francisco’s tree cover is inadequate by the standards of any major city, it is fortunate to have a lot of old trees – many of them over 100 years old. Unfortunately, instead of treasuring these trees – it’s cutting them down. 2019 was a bad year for our trees.


The tall trees around Lake Merced not only add to its beauty, they provide valuable habitat. Cormorants and herons have been nesting there for years.


The trees and bushes lining the road protect the lake from the pollution and noise from the motor traffic on the road – which is likely to increase as an alternate route to bypass the Great Highway.


But – the city has been felling these trees nevertheless. There’s been clearcutting in areas along the roads surrounding the lake.

When we took these pictures, some cormorants were flying back and forth, carrying twigs, perhaps seeking a nesting site that was no longer there. Are these remaining trees along the road also doomed?

Meanwhile, pesticides are going to be used on the stumps of the trees that have already been destroyed.

Pesticide notice on one of the trees that wasn’t felled

This was a majestic tree before it was felled. Lake Merced, San Francisco CA

The nativist sentiment that drives a lot of the antipathy toward eucalyptus is based on  number of myths. The myths about eucalyptus we’ve been trying to counter for years. See HERE for Eucalyptus Myths.

In fact, Lake Merced’s trees have been under attack for years. As far back as 2012, we took these pictures of trees felled inside the park.


It’s not as though San Francisco is so heavily forested that it can afford to wantonly destroy its trees, especially the mature well-established ones. Its tree cover is only 13.7%, less than any major city.

Graph showing urban tree canopy cover in major US cities

San Francisco Has the Least Canopy Cover of any Major US City

In fact, even the city government admits that, in the Planning Department’s Urban Forest Plan.

Small and Shrinking Tree Canopy
San Francisco has one of the smallest tree canopies of any major U.S. city.
San Francisco was naturally a non-forested environment with fewer trees than east coast or other forested environments. Today, the City’s urban tree canopy (13.7%), measured by the amount of land covered by trees when viewed from above, is one of the smallest of any large U.S. city – less than Los Angeles (21%), Chicago (17%) and New York City (24%) – and unfortunately, it’s on the decline. New plantings are not keeping pace with tree removals and mortality, while tens of thousands of potential street tree planting spaces remain empty.”

Cutting down healthy and mature trees is certainly one of the reasons that this tree canopy is shrinking instead of growing.


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