Money and Fire: 2022 Conference of California Native Plant Society

The California Native Plant Society (CNPS) held a conference in October for the first time since 2018.  There were two main themes of the conference:

Money:  The State of California is making a huge investment in the environment with many interrelated goals:

  • “30 X 30” is shorthand for the goal of protecting 30% of California’s land and coastal waters by 2030.
  • Developing “nature-based solutions” to address the threats of climate change.
  • Vegetation and forest management to reduce wildfire hazards.
  • Protecting and enhancing California’s biodiversity.

Fire:  The frequency and intensity of wildfire is of concern to all Californians, but the California Native Society has a particular interest in fire because it is viewed as a tool to enhance native plant abundance and control the spread of non-native plants that outcompete native plants.

Money

If attendance were the sole measure of success, the conference was a resounding success.  The conference was sold out with record-breaking attendance of 1,200 people.  That’s a 50% increase in attendance since 2018, when 800 people attended.  People came to learn about the many opportunities for public funding of their “restoration” projects and they were not disappointed.

Jennifer Norris, Deputy Secretary for Biodiversity and Habitat for the California Natural Resources Agency (CNRA) was one of the keynote speakers.  She and many other staff of CNRA made presentations at the conference to inform the community of native plant advocates about the many new opportunities to obtain grants for their projects.  This slide (below) shown at the conference, itemized by state agencies the $1.631 Billion budget for just the 30 X 30 portion of the CNRA’s environmental grant programs.  It does not include Cal-Fire funding for forestry projects to reduce wildfire hazards and address climate change.  Nor does it include $10 million of new funding for Weed Management Areas, which funds projects that attempt to eradicate non-native plants and $10 million of new funding for the state council for invasive species. State funding is also supplemented by new federal funding in support of a national goal of achieving 30 X 30. 

But money isn’t the only element of this state program that native plant advocates are excited about.  They have also been gifted a three-year moratorium on requirements for Environmental Impact Reports for their projects.  There will therefore be no requirements for a public process to review plans and comment on them. 

An anxious applicant for state grant funding asked a speaker representing the Wildlife Conservation Board about a rumor that projects using herbicides would not be funded.  The speaker’s reassuring answer was, “We are not rejecting projects using herbicides.” Applicants are being asked to complete a questionnaire about herbicides they plan to use, but the speaker was quick to add, “We have not rejected any [such applications] so far.”  She assured the audience that “You are all careful” in your use of herbicides.

Huge buckets of money are being distributed with no restrictions on the use of herbicides and no vetting process such as an environmental impact review with opportunities for the public to comment.  It seems inevitable that some of the projects will unintentionally do more harm than good, and the public will have nothing to say about which projects are funded. 

Fire

Alexii Sigona was the first keynote speaker for the conference.  He is a member of the Amah Mutsun-Ohlone Tribal Band (not a federally recognized tribe) and a Ph.D. candidate at UC Berkeley in the Department of Environmental Science.  He explained that there are 600 recognized members of the Amah Mutsun Band in a wide region around Pescadero, Hollister, and San Juan Bautista.  They collaborate with organizations such as CNPS because they don’t have the resources to manage their ancestral tribal lands.  He described some of the projects they engage in:

  • Landscape scale removal of “invasive” plants.
  • Plug planting of 120,000 native grass plants.
  • Creating “native hedgerows” for food sources.
  • Removal of native Douglas Firs “encroaching” on grassland.  They have removed 5,000 native Douglas fir trees.  He acknowledged that this project caused some concern about erosion and aesthetics.  Removal of native Douglas fir was mentioned by several other speakers during the conference.  It is an example of the preference of native plant advocates for grassland because it is the pre-settlement vegetation.  Native coyote brush is another target of eradication projects that attempt to prevent natural succession of grassland to other vegetation types. 

There is great interest among native plant advocates in the land management practices of Native Americans because controlled burns were Native Americans’ most important tool to maintain grassland species needed for food and for their prey.  Controlled burns are important to native plant advocates because they believe they are beneficial to native plants and help to control non-native plants.  Prescribed burns are also currently popular with many public land managers and they are the current fad among many fire scientists. 

Two presentations at the conference suggest that prescribed burns are not compatible with the preservation of native chaparral, nor are they capable of converting non-native grassland to native grassland.

This (above) is the concluding slide of Jon E. Keeley’s presentation.  Dr. Keeley is a respected fire scientist with US Geological Service with expertise in chaparral species.  He explained that 60% of native chaparral species (notably manzanita and ceonothus) are obligate seeders that do not resprout after fire and therefore depend on the existence of their dormant seed bank for regeneration.  In recent decades the fire interval in chaparral has decreased due to climate change and associated drought.  In many places, the fire interval has become too short to establish the seed bank needed for regeneration.  In those places Dr. Keeley has observed vegetation type conversion to non-native annual grasses. 

Dr. Keeley Is concerned that vegetation type conversion from forests in some cases and shrublands in others to non-native annual grassland may be the result of shortening fire intervals further “because of the upsurge in state and federal programs to utilize prescription burning to reduce fire hazard.” (1) This concern extends to some conifer species that do not resprout.  Some are serotinous conifers whose cones are sealed shut and do not release their seeds in the absence of fire. 

This is a familiar theme for much of Dr. Keeley’s research.  He asks that land managers balance the conflicting goals of resource management and fire hazard reduction. 

This (above) is the concluding slide (sorry for the poor quality of my photo) of a presentation about a 20-year effort at the Santa Rosa Plateau Ecological Reserve to convert non-native annual grassland to native grassland, using annual (sometimes bi-annual) prescribed burns.  Many different methods were used, varying timing, intensity, etc.  The abstract for this presentation reports failure of the 20-year effort:  “Non-native grass cover significantly decreased after prescribed fire but recovered to pre-fire cover or higher one year after fire.  Native grass cover decreased after prescribed fire then recovered to pre-burn levels within five years, but never increased over time.  The response of native grass to fire (wild and prescribed) was different across time and within management units, but overall native grass declined.” (1)

The audience was audibly unhappy with this presentation.  One person asked if the speaker was aware of other places where non-native grass was successfully converted to native grass.  The speaker chuckled and emphatically said, “NO.  I am not aware of any place where native grasses were successfully reintroduced.” 

Another questioner prefaced her question with the admission that “I’m new here and all this is new to me.”  Then she suggested that Native Americans are having some success using prescribed fire and that they should be consulted.  The speaker graciously replied that she planned to do so. 

Keep in mind that Native Americans weren’t historically using prescribed fire to convert annual grasses to native grasses.  Their burns were intended to maintain native grassland in the absence of competing non-native annual grassland.  Their objectives were different and they were operating in a very different climate and environment. 

Estimates of the pre-settlement population of Native Americans in California range from 138,000 to 750,000.  The population of Native Americans is estimated to have been reduced to as few as 25,000 after the arrival of Europeans due to disease and violence.  There are now over 39 million Californians and only 630,000 of them were Native Americans in the 2020 census.  Land management practices that are suitable for a population of less than 1 million seasonally migrating Californians are not necessarily suitable for a population of over 39 million sedentary Californians.   

The futility of trying to eradicate non-native plants

The Invasive Spartina Project (ISP) is another 20-year eradication project that is doomed to failure.  The presentation about the ISP was bravely made by Dr. Debra Ayres, one of the creators of the ISP in 1998.  With intensive effort and hundreds of gallons of herbicide (imazapyr), non-native spartina marsh grass has been greatly reduced in the San Francisco Bay, but the hybrid of non-native S. alterniflora and native S. foliosa persists.  Dr. Ayres explained why:

The spartina hybrid is reproductively stronger in every way than either of its parent species.  Dr. Ayres predicts that the hybrid will eventually replace both of its parent species:

If the goal of this project was to eradicate non-native spartina, hybrid spartina will accomplish that goal. You might think that this prediction would end the futile attempt to eradicate the hybrid, but you would be wrong.  There is no intention of abandoning this 20-year project.  More funding is assured by the California Coastal Conservancy and the project continues to provide well-paid jobs. 

Dr. Ayres ended her presentation with this enigmatic statement:  Evolution doesn’t stop just because we think it has to.”  She seems to acknowledge that humans cannot stop evolution, yet she seems to recommend that we continue to try doing so.  If those positions seem contradictory, that’s because they are.  The bottom line is that as long as public funding continues to be available, this project will continue.

A central theme of the nativist agenda is the futile desire to prevent hybridization because it has the potential to replace a species considered “native.”  They fail to understand that hybridization is an important evolutionary tool that helps plant and animal species adapt to changes in environmental conditions by favoring traits that are better adapted to new conditions.  Humans cannot stop evolution, nor should we try.

San Francisco

I have a special interest in San Francisco because I lived there for nearly 30 years.  The native plant movement is very strong in San Francisco and there were several presentations about the success of the movement at the conference.

Sunset Blvd being built on barren sand in 1931

One of the projects is trying to turn Sunset Blvd on the western side of San Francisco into a native plant garden.  I lived in that district and am therefore familiar with Sunset Blvd as the major north-south traffic artery through the district.  It is important as the only wind break in the windiest district of the city, which is only 13 short blocks from the ocean.  The district is virtually treeless because of wind conditions and the pre-settlement landscape of barren sand.  Sunset Blvd is therefore the oasis of the Sunset District.  In the past, it was the only place to take a long walk in the shelter of the tall Monterey pines and cypress and tall-shrub understory.  The lawn beneath the trees was the only place for children to play close to their homes.

San Francisco’s Department of Public Works (DPW) is responsible for maintaining the medians in San Francisco.  It was therefore DPW’s responsibility to replace the wind break on Sunset Blvd that is dying of old age.  That’s not what they chose to do.  They are replacing the lawn with native shrubs and the tall trees with small native trees that won’t provide shelter from the wind. 

The spokesperson for DPW acknowledged that the project is controversial.  Neighbors of Sunset Blvd valued the sheltered recreational space provided by the 2.5 mile-long and wide median.  Native plant advocates and their allies want to create a wildlife corridor through the western edge of the city.  The spokesperson for DPW said that their plans are a compromise between these different viewpoints.  I don’t know if the neighbors agree, but I can say that native plant advocates are thrilled with the new native plant gardens on Sunset Blvd based on their presentation at the CNPS conference.

Planting Sunset Blvd. with native plants, December 2020

Native plant advocates prevailed on Sunset Blvd because CNPS bought or raised all the native plants and provided volunteers to plant them and maintain them for 3 years.  DPW couldn’t look their gift horse in the mouth. DPW hired 6 new gardeners to support maintenance of Sunset Blvd. This is an example of how the money that is flowing into such projects will transform many places into native plant gardens. 

Sunset Blvd and Taraval, spring 2022

So, let’s look at the result of these projects.  Presenters of these projects showed many beautiful pictures of newly planted native gardens on Sunset Blvd (above).  The pictures were taken in spring, when native plants briefly flower.  But that’s not what these places look like most of the year.  They will look better if they are irrigated year-round, but that would defeat the purpose of replacing the lawn to reduce water usage.  Unlike native plants, lawn turns brown during the dry season if it isn’t watered, but it is still functional as walkable ground. 

Here’s what that garden at Sunset Blvd and Taraval looks like most of the year:

Sunset Blvd & Taraval, October 23, 2022

There was also a presentation by a spokesperson from San Francisco’s Public Utilities Commission (PUC) about the creation of rain gardens in San Francisco.  San Francisco’s sewer system was built long ago when regulations did not require the separation of street run off from residential sewage.  When it rains, the sewage treatment plant is overwhelmed by street run off.  The sewage treatment plant releases untreated sewage and run off into the ocean, in violation of federal standards for water treatment. 

Rain garden on Sunset Blvd as shown at the CNPS Conference
Rain Garden on Sunset Blvd in August 2022. They aren’t pretty year around.

The PUC is developing rain gardens to redirect street run off away from sewage treatment plants into the ground so that treatment plants are not overwhelmed during heavy rain.  The San Francisco Chronicle recently reported that 151 rain gardens have been installed so far. It seems a very good idea, but native plant advocates are not happy with the rain gardens because the PUC has not made a commitment to plant exclusively native plants in the rain gardens.  The audience pressured the speaker about this issue.  He advised them to lobby the PUC to make a commitment to plant only native plants in the rain gardens.  I have no doubt that they will take his advice.  Given their influence and their access to public funding, I would be surprised if the PUC continues to resist their demands.

Conclusion

I have undoubtedly exhausted your patience, although there is much more I could tell you about, including several projects that look promising because they are exploring the importance of soil health to achieve successful results.

The conference themes in 2022 were consistent with the previous two conferences I have attended since 2015.  This is my summary of the fundamental errors of the nativist agenda in the natural world.  They are as apparent in 2022 as they were in 2015: 

  • The futility of trying to eradicate non-native plants that are better adapted to current environmental conditions.
  • The futile and harmful attempts to prevent natural succession and hybridization.
  • The contradictory goals of fuels management and resource management.
  • The lack of understanding that vegetation changes when the climate changes.  The ranges of native plants have changed and will continue to change.  The pre-settlement landscape of the 18th century cannot be recreated.
  • The lack of understanding of the importance of soil health to ecological restoration and associated ignorance (or denial) of the damage that pesticides do to the soil. 

(1) Abstracts for all presentations are available on the CNPS website.

Creating Tree Graveyards in San Francisco

At 13.7% of tree canopy coverage, San Francisco has one of the smallest tree canopies of any major city in the country.  When San Francisco’s Urban Forestry Council (UFC) announced its goal of planting 30,000 new street trees in the next 20 years, it seemed a modest goal.  Yet, Jake Sigg, the leader of native plant advocates in San Francisco, immediately objected to even this modest goal in his Nature News.  He announced the meeting of the UFC to consider the proposal and pronounced it a bad idea:

“JS:  Let’s start taking climate change seriously.  There is a prejudice—it is nothing more than that—that trees sequester more carbon than other life forms.  That is a simplistic view that, when looked at more closely, is found wanting.  To counter climate change we need to remove carbon from the air and put it where it will be for a millennium or more.  Removing it for a few decades or a century is pointless. 

“There are many reasons to plant trees on San Francisco streets, and many of our streets need them.  Climate change is not a stand-alone phenomenon; it is intimately related to diversity of biological elements.  That argues for planting native plants to invite dispossessed wildlife back into the city and you do that by planting the plants they need.  There are trees, shrubs, and perennials that ought to line our street to function in this way.  Carbon removal should not be a factor in our street plantings—biodiversity should be Number 1.”

Jake Sigg, Nature News, July 2, 2022

Yes, Jake, biodiversity is important because a diverse ecosystem is more resilient in a changing climate, but destroying all non-native plants does not make an ecosystem more diverse.  Climate change is the greatest long term threat to biodiversity, which makes addressing climate change a prerequisite to preserving biodiversity. 

I attended the Urban Forestry Council meeting of July 5, 2022, when this proposal was considered.  I was expecting to hear objections from Jake Sigg’s followers. Instead, the handful of written public comments objected to the meager commitment to plant only 30,000 new trees in San Francisco in the next 40 years. I learned more about the plan to plant more street trees in San Francisco:

  • There are presently an estimated 125,000 street trees in San Francisco.
  • Because the mortality of street trees is high, the expectation is that 50,000 street trees would need to be planted in the next 20 years to replace dead street trees.
  • According to the Urban Forestry Council it costs $1,500 to plant a tree and an additional $2,500 to water it for three years until it is established.
  • 4,000 trees would need to be planted every year to keep pace with expected tree mortality and to add 30,000 more street trees. 

These goals exist only on paper.  Between 1,500 and 2,000 trees per year are being planted in the city and no funding has been identified to increase this number.  After delivering this bad news about the sorry state of San Francisco’s urban forest, one member of the UFC spoke some much needed common sense.  Nicholas Crawford said we should “hold onto shabby trees” that are established and storing carbon.  He suggested that San Francisco should not remove trees that are at least stable because there are no trees to replace them. 

Existing trees in our urban forest are more valuable than ever.  They are storing more carbon than a replacement tree will store for at least 20 years.  They don’t need to be irrigated because they have the root and fungal networks needed to supply the tree with the moisture it needs.  Existing trees have proven themselves.  The fact that they are alive and well after 10 years of extreme drought proves they are adapted to current climate conditions.  So why destroy them? 

Jake Sigg acknowledged the value of forests to address the challenges of climate change in a recent newsletter:  “In order to have an impact on climate we need to stop deforestation and preserve, strengthen, and restore what is already here.” (Nature News, July 6, 2022)  But that principle does not apply to San Francisco for Sigg and his followers because the trees of San Francisco are predominantly non-native and they place a higher value on restoring pre-settlement treeless grassland and coastal scrub.  Because of the power and influence of the native plant movement in San Francisco our urban forest is being destroyed and planting trees is resisted.

San Francisco has made a commitment to destroying more than 18,000 non-native trees in San Francisco’s public parks.  The stated goal of that program is a landscape of native grassland and scrub.  UC San Francisco has also made a commitment to destroy most of the non-native forest on Mount Sutro.  Thousands of trees have been destroyed on Mount Sutro and more will be destroyed in the future.  The Executive Director of Sutro Stewards, the non-profit organization that is implementing the plans for destruction of the non-native forest on Mount Sutro is represented on the Urban Forestry Council, an odd choice for a citizen’s advisory council theoretically committed to the urban forest.

Tree destruction on Mount Sutro, January 2021.  Courtesy San Francisco Forest Alliance

McLaren Park:  A Case Study

Today Conservation Sense and Nonsense will visit a relatively new project in McLaren Park that has destroyed non-native trees in order to create a small native plant garden.  We drill down into the project to understand why San Francisco’s urban forest is being destroyed.  We visit this project because it is an example of many similar projects that are planned in San Francisco. 

This is one of many attempts to plant native plant gardens on Sunset Blvd in San Francisco. The functional windbreak of Monterey cypress is dying of old age. Rather than replace the windbreak, native shrubs are being planted on Sunset Blvd that will not function as a windbreak in the windiest district in San Francisco. The lack of maintenance that you see here is typical of these gardens, which makes them unpopular with neighbors.

At 312 acres, McLaren Park is one of the largest parks in San Francisco.  Fifty-three percent (165 acres) of McLaren Park is designated as a “natural area,” which means that a commitment was made nearly 25 years ago to transform it into a native plant garden.  The new native plant garden that we visit today is not actually inside one of the designated “natural areas.”  The reach of the native plant movement in San Francisco extends far beyond the 1,100 park acres of “natural areas” that were claimed in 1998. 

The new native plant garden is located in the southeast corner of McLaren, south of the community garden at the intersection of Visitation Ave and Hahn St.  This is a photo of some of the trees that were destroyed to create the native garden:

©Lance Mellon with permission.  July 2020

And this is a photo taken in December 2021, after the trees deemed “non-native” were destroyed:

© Lance Mellon with permission

The plans for the native plant garden say that 18 non-native trees would be destroyed and 6 native trees would be retained.  The plan claims that tree removals of all non-native trees were based on “professional assessments.”  Such “assessments” are routinely used by the Recreation and Park Department to justify the removal of non-native trees.  Photos of the trees indicate otherwise.  Retention of only native trees suggests that assessments aren’t even-handed.  The claim does not pass the smell test. 

Plans for the native plant garden indicate that more native trees will be planted:

The trees will need to be irrigated for at least 3 years to establish their root systems and ensure their survival.  The entire garden will need to be irrigated if it is to survive.  Let’s be clear:  an established grove of trees with an understory of annual grasses that did not require irrigation or maintenance was destroyed and replaced with new plants and trees that will require irrigation.  Is that a suitable use of scarce water resources during an extreme drought that is expected to get worse, if not be a permanent change in the climate?  That is the question we consider today.

About 9 months later, the “native plant garden” looks more like a tree graveyard:

McLaren Native Plant Garden, July 2022
Some of the newly planted trees are holly leaf cherry. Signs on the trees indicate that the project was paid for with a CAL FIRE grant. One wonders how a garden full of dead wood is less flammable than a garden full of living trees.

Granted, the native plant garden is likely to look better as plants grow.  However, it will only look better if it is irrigated and taken care of.  Why should we expect it to be taken better care of than the existing garden that required no maintenance?  Wishful thinking will not make it so.

The death grip of nativism

Climate change is the environmental issue of our time.  We are seemingly incapable of doing anything substantive to address climate change.  Political gridlock prevents us from controlling the greenhouse gas emissions causing climate change.  The Supreme Court recently ruled that the Environmental Protection Agency does not have the authority to regulate polluting emissions from power plants. 

We focus on the preservation of our forests because it is the only tool we have left to absorb carbon emissions from the fossil fuels to which we are wedded.  Native plant advocates have taken that tool away from us.  Our urban forests are being destroyed and replaced with grassland and scrub.  Claims that grassland and scrub store more carbon than forests are ridiculous.  Those claims earn native plant advocates the label of climate change deniers.  As the drought continues to plague California, established landscapes that required no water are being destroyed and replaced with native plants that require irrigation. 

California Natural Resources Agency writes a BIG blank check to the “restoration” industry

California Natural Resources Agency has published the draft of “Pathways to 30X30 California” and has invited the public to comment on the draft by February 15, 2022.  “Pathways to 30X30” is the last in a series of documents that defines the program before implementation in February 2022, when distribution will begin of $15 Billion dollars to public and non-governmental agencies to fund specific projects. 

To recap the process that began in October 2020 with the passage of an Executive Order:

  • In October 2020, Governor Newsom signed Executive Order N-82-20 “enlisting California’s vast network of natural and working lands – forests, rangelands, farms, wetlands, coast, deserts and urban greenspaces – in the fight against climate change. A core pillar of Governor Newsom’s climate agenda, these novel approaches will help clean the air and water for communities throughout the state and support California’s unique biodiversity.” The program and its implications are described by Conservation Sense and Nonsense HERE.
  • California Natural Resources Agency held a series of public workshops in summer 2021 that were theoretically an opportunity for the public to participate in the process of defining the program.  Conservation Sense and Nonsense identified potential opportunities as well as pitfalls of the program HERE.
  • California Natural Resources Agency published the first draft of implementation plans in fall 2021.  Conservation Sense and Nonsense published its favorable opinion of the first draft that is available HERE.

The draft of the final implementation document is disappointing.  My public comment on the draft of “Pathways to 30X30” is below.  To preview it briefly here, this is its concluding paragraph:  “California’s 30X30 initiative had great potential to improve the environment rather than damaging it further.  Instead, draft “Pathways to 30X30” suggests that opportunity may be squandered.  Of course, the proof will be in the projects, but for the moment it looks as though the lengthy public process may have been a charade intended to benefit the “restoration” industry, not the environment or the public.”

Please consider writing your own public comment by February 15, 2022.

  • Email: CaliforniaNature@Resources.ca.gov;
  • Letter via postal mail: California Natural Resources Agency, 715 P Street, 20th Floor, Sacramento, CA 95814;
  • Voice message: 1 (800) 417-0668.
  • There will be a virtual meeting on Tuesday, February 1, 2022, 3-6 pm in which the public will be invited to make 2 minute comments.  Register HERE.

TO:        California Natural Resources Agency

RE:         Public comment on draft “Pathways to 30X30”

I have attended the public workshops regarding the 30X30 initiative and sent written feedback when given the opportunity.  I am therefore in a position to tell you that the “Draft Pathways to 30X30” is a significant retreat from principles defined by previous drafts because it is so vague that it is meaningless. Any project could be approved within its limitless boundaries. The document puts CNRA in the position to do whatever it wishes, including violate principles defined in previous draft documents.

My public comment is a reminder of commitments made in previous drafts and a request that they be reinstated in the final version of the Draft “Pathways to 30X30” document:

  • “Pathways to 30X30” must confirm its commitment to reducing the use of pesticides on public lands.  The draft mentions the need to “avoid toxic chemicals” only in the context of working lands.  That commitment must also be made for public parks and open spaces because widespread pesticide use is exposing the public and wildlife to dangerous pesticides and killing harmless plants while damaging the soil.
  • Unlike the previous draft, “Climate Smart Strategy,” “Pathways to 30X30” requires the exclusive use of native plants, which contradicts the commitment to “promote climate-smart management actions.”  The ranges of native plants have changed and must continue to change because native plants are no longer adapted to the climate.  We cannot reduce greenhouse gas emissions causing climate change if we cannot plant tree species that are capable of surviving in our changed climate, as acknowledged by previous draft documents. As Steve Gaines said in the January 12th public meeting regarding “Pathways to 30X30,” “We must help species move [because the changing climate requires that they do].”

There are significant omissions in “Pathways to 30X30” that epitomize my disappointment in this draft:

  • The draft kicks the can down the road with respect to integrating climate change into consideration of projects funded by the initiative:  “Designations have not yet been established that emphasize climate benefits such as carbon sequestration or buffering climate impacts. While the definition of conserved lands for 30×30 builds upon existing designations, it will be important to integrate climate…” (pg 26)  Climate change is the underlying cause of most problems in the environment, yet “Pathways to 30X30” dodges the issue by declining to take the issue into consideration as it distributes millions of grant dollars to projects that are toxic band aides on the symptoms of climate change.
  • The 30X30 initiative made a commitment to protecting 30% of California’s land and coastal waters.  At 24%, we are close to that goal for land, but at only 16% we are far from the goal for coastal waters.  Yet, the draft declines to protect more marine waters:  “MPA [Marine Protected Areas] Network expansion will not be a component of meeting the State’s 30×30 marine conservation goals.” (pg 29, deeply embedded in fine print) The excuse for this omission is that the decadal review of existing MPAs won’t be completed for another year.  That is not a legitimate reason for refusing to designate new MPAs.  The evaluation of existing MPAs can and should be completed and inform the management of new MPAs going forward. 

The lack of guidance in “Pathways to 30X30” is particularly dangerous because California law has recently been revised to exempt projects considered “restorations” from CEQA requirements for Environmental Impact Reports for three years, ending January 1, 2025. An Environmental Impact Report is the public’s only opportunity to preview planned projects and challenge them within the confines of CEQA law.  The public is effectively shut out from the process of distributing millions of grant dollars of the public’s tax money by this blanket exemption on CEQA requirements for an EIR. 

The Draft of “Pathways to 30X30” writes a big blank check for projects that will potentially increase the use of pesticides on our public lands and increase greenhouse gas emissions by destroying plants and trees that sequester carbon and are capable of surviving our current and anticipated climate. 

California’s 30X30 initiative had great potential to improve the environment rather than damaging it further.  Instead, draft “Pathways to 30X30” suggests that opportunity may be squandered.  Of course, the proof will be in the projects, but for the moment it looks as though the lengthy public process may have been a charade intended to benefit the “restoration” industry, not the environment or the public. 

Looking for Godot: Finding achievable restoration goals

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.

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. 

How have land managers responded to the dangers of herbicides?

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.

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.

Looking for an alternative to 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 not a magic bullet

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.

Reaching a dead—and deadly—end

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 is offering free video training for non-chemical methods of killing “invasive” plants on May 4, 2021, 1-5 pm.  Sign up HERE. 

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

Study design determines study findings

Million Trees can never resist a response to misinformation we find in Jake Sigg’s Nature News. (In this case, the statement originates with one of Jake’s readers, not Jake himself.)

“This study takes some of the life out of Art Shapiro’s ecological fitting theory:  Non‐native plants supported significantly fewer caterpillars of significantly fewer specialist and generalist species even when the non‐natives were close relatives of native host plants.”  “Non-native plants reduce abundance, richness, and host specialization in lepidopteran communities” by Karin Burghardt, Doug Tallamy, et, al. (Ecosphere, November 2010).

We’ll get to the study later, but first let’s address the statement about ecological fitting.  Ecological fitting is more accurately described as an observation, rather than a theory or hypothesis and it does not originate with Art Shapiro.  The first observation of ecological fitting was recorded by Dan Janzen in 1980 and described by other ecologists as “the process whereby organisms colonize and persist in novel environments, use novel resources or form novel associations with other species as a result of the suites of traits that they carry at the time they encounter the novel condition.” (1) Ecological fitting is an alternative to the view that relationships between plants and insects and parasites and hosts are the result of co-evolution.  It is consistent with the observation that adaptation to new arrivals in an ecosystem often occurs without evolutionary change and can occur more rapidly than co-evolution would require.

The Colorado potato beetle readily devours an introduced relative of its Solanum hosts as a result of ecological fitting.  (Hsiao, T. H. (1978). “Host plant adaptations among geographic populations of the Colorado potato beetle”. Entomologia Experimentalis et Applicata. 24 (3)) USDA photo

Ecological Laboratory Science

The Burghardt/Tallamy study is a laboratory experiment in the sense that it creates an artificial environment by planting a garden in which it chooses the plant species and then inventories the insect visitors to the garden.  In one garden, native plant species were paired with a closely related species of non-native plant in the same genus (called congeners).  In another, distant garden, native plant species were paired with unrelated species of non-native plants.  The insect visitors that were counted are specifically the larvae stages (caterpillars) of lepidoptera (moths and butterflies).  The adult stage of the caterpillars (moths and butterflies) were not inventoried, nor were members of the other 28 insect orders.

Source: handsontheland.org

The study considers caterpillars “specialists” if they feed on three or fewer plant families.  The authors make this determination based on scientific literature and on observations of their artificially created garden.  Using scientific literature, 30% of visiting caterpillar species to the experimental garden were specialists.  Using actual visits to their experimental garden, 64% of visiting caterpillars were specialists.  The difference is as we should expect because the scientific literature is based on the behavior of caterpillars in the field, but the study confines the choices of the caterpillars to a few specific plant species chosen by the authors of the study.  In other words, caterpillars in the experimental garden had fewer choices of plant species.

The inventory of caterpillars was conducted over two summer months in 2008 and three summer months in 2009.  Findings were very different in the two years of the study:  “We found no difference between the total Lepidoptera larvae supported by native plants and their non-native congeners in 2008, but found over three fold more larvae on natives in 2009.  In 2008 there was no difference in the abundance of generalists on native and non-native congeners, but natives supported more than twice as many generalists as non-natives in 2009.” (2) Similar results were reported for species richness (number of different larvae species).  When paired with unrelated non-native plants, caterpillars showed a significant preference for native plant species, as we should expect because the plants were not chemically similar.

Caterpillar of Anise swallowtail butterfly on its host plant, non-native fennel. Berkeley, California

Although on average, native species attracted more caterpillars than the non-native congener with which they were paired, the strength of that difference varied significantly.  One matched pair attracted eight times as many caterpillars to the native plant compared to the non-native plant.  Another matched pair attracted slightly more caterpillars to the non-native plant compared to the native plant.  

The study authors interpret the significant differences between findings in the first and second years as an indication that caterpillars accumulated more rapidly on native plants than on non-native plants.  They speculate that a longer study would have found even greater preferences for native plants compared to non-native congeners.  Given that adaptation to introduced species occurs over time that is a counter-intuitive prediction.  In fact, many studies find that insects have made a successful transition from native to non-native hosts within a few generations.

Limitations of laboratory studies

The Burghardt/Tallamy study is often cited by native plant advocates in support of their belief that insects require native plants for survival.  This generalization is not supported by the results of the Burghardt/Tallamy study because:

  • The study results are not relevant to all insects.  The findings apply only to the larvae stages of moths and caterpillars.  The adult stages of moths and butterflies also require nectar and pollen from a much broader range of plants than their host plant, where the adult lays its eggs and caterpillars feed before becoming flying adults.  At the adult stage of their lives, they become pollinators.  Studies of the preferences of pollinators consistently find that a diverse garden that prolongs the blooming period is most useful to them. 
  • The study does not support the claim that caterpillars consistently choose native plants in preference to closely related non-native plants over time.  In fact, other studies find such preferences fade over longer periods of time.
  • Statements made by native plant advocates about the degree to which caterpillars are “specialized” are often exaggerated.  When a diverse landscape is available to caterpillars, scientific literature reports that specialization to a few plant families is found in only 30% of the 72 caterpillar species identified by this study. 
  • The Burghardt/Tallamy study was conducted on the East Coast where the climate is different than California.  It snows in the winter and it rains during the summer, unlike most of California.  Our native plants are therefore different from natives on the East Coast.  The Burghardt/Tallamy study was conducted in the summer months from June to August.  Native plants in California are no longer blooming and many are dormant during summer months unless they are irrigated.  The findings of the Burghardt/Tallamy study are therefore not applicable to California unless they can be replicated here.
This is the Serpentine Prairie in Oakland. It is one of the native plant “restorations” done by East Bay Regional Park District. About 500 trees (including native oaks) were destroyed to return the prairie to native grassland. This is what it looks like in June.

Comparison of laboratory with field studies

The Burghardt/Tallamy study 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.  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. 

Anise Swallowtail butterfly in non-native fennel. Courtesy urbanwildness.org

The credibility and relevance of Professor Shapiro’s studies are also based on 47 years of visiting his research plots at least 250 days per year, that is, year around.  During that period of time, he recorded his observations and they were statistically analyzed for the study he published in 2003. (3)  His study is of particular interest as the climate changes rapidly because the length of the study also enables us to observe the impact of climate change on our butterfly population in the Bay Area.  In contrast the Burghardt/Tallamy study was conducted in a total of 5 months over a total of two years.  Population trends cannot be determined from such a short study.

Burghardt/Tallamy study is consistent with mission of Million Trees

The Burghardt/Tallamy study does not contradict anything Million Trees advocates for.  Decisions to plant a particular species and the decision to eradicate a particular species are entirely different.  Gardeners should plant whatever they prefer, in my opinion.  When planting decisions are made for public land, I prefer that plants be capable of surviving current local and climate conditions.  When my tax dollars are being spent, I prefer that they not be wasted. Besides, I hate watching plants and trees die in the parks I visit.

This study is consistent with my view that non-native plants don’t threaten the survival of insects unless they replace native plants that insects prefer.  The Burghardt/Tallamy study quite rightly does not say that they do.  Local experience in the Bay Area informs me that they rarely do.  To the extent that they have replaced native plants, they are better adapted to current conditions in a specific location.  Eradicating them rarely results in native plants successfully replacing them.  As the climate continues to rapidly change, the failure of native plant “restorations” is inevitable because vegetation changes when the climate changes.

Site 29 on Claremont Blvd in Oakland is one of the places where UC Berkeley destroyed about 19,000 trees about 14 years ago. Non-native weeds thrive in the sun where trees were destroyed. Poison hemlock and thistle are 8 feet tall where not sprayed with herbicide. Site 29, May 2016.

The Burghardt/Tallamy study does not justify eradication of non-native plants because it does not take into account the damage done by the methods used to eradicate non-native plants.  Since most eradication projects use herbicides, we speculate that more harm is done to insects by herbicides than by the existence of non-native plants.

The decision to eradicate non-native plants must also take into consideration whatever benefit the plants may provide, such as food for wildlife.  For example, even if a plant species isn’t a host plant, it might be a food plant. Butterfly bush (Buddleia) is an example of a plant that is very useful to pollinators, including butterflies, but native plant activists advocate for its eradication. 

Monarch nectaring on butterfly bush. butterflybush.com

Many thanks to Jake Sigg for creating this opportunity for dialogue with native plant advocates.  I am grateful for the window into the community of native plant advocates that Jake’s Nature News provides.

  1. Agosta, Salvatore J.; Jeffrey A. Klemens (2008). “Ecological fitting by phenotypically flexible genotypes: implications for species associations, community assembly and evolution”. Ecology Letters11 (11): 1123–1134. 
  2. “Non-native plants reduce abundance, richness, and host specialization in lepidopteran communities” by Karin Burghardt, Doug Tallamy, et, al. (Ecosphere, November 2010).
  3. SD Graves and AM Shapiro, “Exotics as host plants of the California butterfly fauna,” Biological Conservation, 110 (2003) 413-433

Oyster Bay: A firehose of public funding supplies a firehose of herbicides

Oyster Bay is one of several East Bay Regional Parks along the east side of the bay that is a former garbage dump built on landfill.  We visited Oyster Bay for the first time in 2011 after a former Deputy General Manager of the park district told us that it is a “beautiful native plant garden” and a model for a similar project at Albany Bulb, another former garbage dump being “restored” by the park district.

When we visited seven years ago, we found a park in the early stages of being destroyed in order to rebuild it as a native plant museum.  Since there were never any native plants on this landfill, we can’t call it a “restoration.”  We took many pictures of the park in 2011 that are available HERE.

We recently decided it was time to revisit the park when we noticed pictures of it in the recently published annual report of the park district’s Integrated Pest Management program, indicating recent changes in the development of the park.  My article today is about what is happening now at Oyster Bay.  It is still not a “beautiful native plant garden.”

“Restoring” grassland

Non-native annual grassland. Oyster Bay April 2011

Seven years ago, most of Oyster Bay was acres of non-native annual grasses.  Since then, most of those acres of grassland have been plowed up and are in various stages of being planted with (one species?) native bunch grass (purple needle grass?).

Stages of grassland conversion. Oyster Bay May 2018

On our May 1st visit, there were at least 8 pesticide application notices posted where the native bunch grass has been planted.  Several different herbicides will be used in those sprayings:  glyphosate, Garlon (triclopyr), and Milestone (aminopyralid).

Herbicide Application Notices, Oyster Bay May 2018

Grassland “restoration” in California is notoriously difficult.  Million Trees has published several articles about futile attempts to convert non-native annual grassland to native grassland:

We wish EBRPD good luck in this effort to convert acres of non-native annual grass into native bunch grass.  Frankly, it looks like a lot of public money down the drain to us.  It also looks like an excuse to use a lot of herbicide.  Who benefits from this project?  Not the taxpayer.  Not the park visitor who is now exposed to a lot of herbicide that wasn’t required in the past.  Not the wildlife, birds, and insects that lived in and ate the non-native vegetation. (We spotted a coyote running through the stumps of bunch grass.  Was he/she looking for cover?)

Redwing blackbird in non-native mustard. Oyster Bay May 2018

Destroying trees and replacing them

P1010129
Pittosporum forest was an excellent visual screen, sound barrier, and wind break. It was healthy and well-suited to the conditions on this site. It was probably home to many animals. Oyster Bay April 2011

When we visited Oyster Bay in 2011, many trees had already been destroyed, but there was still a dense forest of non-native pittosporum.  That forest is gone and the park district has planted one small area with native trees as a “visual screen” of the Waste Management Facility next door.  We identified these native trees and shrubs:  ironwood (native to the Channel Islands), coast live oak, buckeye, toyon, juniper, mallow, holly leaf cherry, and redbud.

Native trees planted at Oyster Bay, May 2018

Ground around trees is green with dye used when herbicide is sprayed. Oyster Bay, May 2018

We also saw a notice of herbicide application near the trees.  The ground around the trees was covered in green dye, which is added to herbicide when it is sprayed so that the applicator can tell what is done.  There were men dressed in white hazard suits, driving park district trucks, apparently getting ready to continue the application of herbicides.

Will the trees survive this poisoning of the soil all around them?  There are many examples of trees being killed by spraying herbicides under them.  Herbicides are often mobile in the soil.  Herbicides damage the soil by killing beneficial microbes and mycorrhizal fungi that facilitate the movement of water and nutrients from the soil to the tree roots.

Herbicide sprayed around newly planted trees. Oyster Bay May 2018

Not a fun day at the park

It wasn’t a fun day at the park and it isn’t fun to write about it.  I decided to tell you about this visit after reading the most recent edition of the Journal of the California Native Plant Society, Fremontia (Vol. 46 No. 1).  The introductory article of this “Special Issue on Urban Wildlands” is illustrated with a photo of Oyster Bay.  I nearly choked on this statement in that article:  “In order to control invasive plants, agencies and volunteers have sometimes resorted to using herbicides as a step in integrated pest control.  While use of herbicides is contentious, the use for spot treatments has enabled small groups of volunteers to successfully eliminate invasive weeds in some areas where future herbicide use will not be needed.” 

That is a PATENTLY FALSE statement.  The California Invasive Plant Council conducted a survey of land managers in 2014.  Ninety-four percent of land managers reported using herbicides to control plants they consider “invasive.”  Sixty-two percent reported using herbicides frequently.  The park district’s most recent IPM report for 2017 corroborates the use of herbicides to eradicate plants they consider “invasive.”  The park district report also makes it clear that they have been spraying herbicide for a very long time.  For example, they have been spraying non-native spartina marsh grass (in the bay and along creeks) with imazapyr for 15 years!

Attempting to eradicate non-native plants is NOT a short-term project.  It is a forever commitment to using herbicides…LOTS of herbicide.  To claim otherwise is to mislead, unless you are completely ignorant of what is actually being done. 

You are paying for this

Another reason why I am publishing this article is to inform you that you are paying for these projects.  The park district recently published a list of 492 active park improvement projects in 2018 (scroll down to page 71), many of which are native plant “restorations.” The majority of them are being paid for with grants of public money from federal, State, and local agencies as well as a few parcel taxes.  Taxpayers had the opportunity to vote for the parcel taxes.  They will have the opportunity to vote for new sources of funding for these projects:

  • Proposition 68 will provide $4.1 BILLION dollars for “park and water” improvements. It will be on your ballot on June 5, 2018. Roughly a third of the money will be allocated for “protection of natural habitats.” (1) Although the project at Oyster Bay does not look “natural” to us, that’s how the park district and other public agencies categorize these projects that (attempt to) convert non-native vegetation to native vegetation.
  • Measure CC renewal will be on the ballot in Alameda and Contra Costa counties on November 6, 2018.  The park district has made a commitment to allocate 40% of the available funding to “natural resource projects.” Although the anticipated revenue (about $50 million) seems small, it is used as leverage to apply for big State grants, which require cost-sharing funding.  Measure CC is essentially seed money for the much bigger federal and State funding sources.

I would like to vote for both of these measures because our parks are very important to me.  If voting for these measures would actually improve the parks, I would do so.  But that’s not what I see happening in our parks.  What I see is a lot of damage:  tree stumps, piles of wood chips, dead vegetation killed by herbicides, herbicide application notices, signs telling me not to step on fragile plants, etc.

Stay out of Oyster Bay to avoid unnecessary exposure to herbicides and keep your dogs out of Oyster Bay for the same reason. Unfortunately wildlife doesn’t have that option. They live there. Oyster Bay, May 2018


  1. “States big bond for little projects,” SF Chronicle, May 5, 2018

Parks for the future, not the past

East Bay Regional Park District is preparing to put a parcel tax on the ballot in 2018 that will extend the funding of park improvements for another 15 years.  The public has been invited to tell the park district what improvement projects should be funded by the parcel tax in the future.  We are publishing a series of such public comments that we hope will inspire the public to submit their own suggestions to the park district. 


TO:         publicinformation@ebparks.org

CC:         Board of Directors

FROM:  Park Advocate

RE:          Suggestion for Measure CC Projects

Climate change is the environmental issue of our time.  The climate has changed and it will continue to change.  If park improvement projects are going to be successful, they must have realistic goals that take into consideration the changes that have occurred and the changes anticipated in the future.

The restoration of native grassland is an example of a project that is not realistic, given current environmental conditions.  Grassland in California has been 98% non-native annual grasses for over 150 years.  Mediterranean annual grasses were brought from Mexico to California by the cattle of the Spaniards in the early 19th century.

David Amme is one of the co-founders of The California Native Grass Association and was one of the authors of East Bay Regional Park District’s “Wildfire Hazard Reduction and Resource Management Plan” while employed by EBRPD. In an article he wrote for Bay Nature he listed a few small remnants of native grasses in the East Bay and advised those who attempt to find them, “As you go searching for these native grasses, you’ll see firsthand that the introduction of the Mediterranean annual grasses is the juggernaut that has forever changed the balance and composition of our grasslands.”   That article is available HERE.

The park district seems to understand the futility of trying to transform non-native annual grassland to native bunch grasses.  Here are two signs in two of the EBRPD’s parks that acknowledge the reality of California’s grassland.

Serpentine Prairie, April 2017

Tilden Park, Inspiration Point, October 2016

Yet, despite this acknowledgement, the park district continues to expand its efforts to transform the parks into native grassland.  Park visitors recently observed a failed experiment to introduce native grasses to one of the parks.  Six plots of ground were fenced.  Two of the plots were control plots in which whatever non-native weeds had naturalized were allowed to grow unmolested.  Two of the plots were mulch/seeded with native grasses and two of the plots were fabric/seeded with native grasses.  There was no observable difference in plant composition or abundance between the seeded and unseeded plots.  There was no observable difference in the outcome of the two different seeding methods that were used.  In other words, native grasses were not successfully introduced to this park.  My correspondence with the EBRPD employee who was responsible for this project is attached.

Albany Bulb, April 2017

Albany Bulb, April 2017

The park in which this experiment was conducted is Albany Bulb.  Albany Bulb is the former garbage dump of the City of Albany.  It was built on landfill in the bay.  The soil is not native and there were never any native plants on it.  It does not seem a promising candidate for a native plant “restoration.”  Unfortunately, Albany Bulb is not an atypical park along the bay.  There are many other parks along the bay that were built on landfill and in which the park district is attempting to establish native plant gardens.  This does not seem a realistic objective for these parks.

 

 

 

 


Albany Bulb April 2018

Update:  One year after the experimental planting of native wildflowers at Albany Bulb, there is no evidence of that effort.  The trail-sides are mowed weeds and the upslope from the trail is studded with blooming non-native oxalis and wild radish. 

Albany Bulb. Non-native wildflowers. April 2018

Albany Bulb will soon be closed to the public for a major “improvement” project.   Albany Landfill Dog Owners Group and Friends expects the park to be closed for about one year.  They are unsure if the park will allow dogs off leash when the park re-opens.  More information about the “improvement” project is available on their website:  http://www.aldog.org/announcements-2.  They suggest that you sign up on their website to be notified of the progress of the project and the status of the re-opening of the park.

 

 


 

This is not to say that there aren’t many worthwhile park improvement projects that are both realistic and needed.  Dredging Lake Temescal is an example of a worthy project.  As you know, Lake Temescal was a popular place for people to swim until recently.  In the past few years it often has been closed to the public because of toxic algal blooms.  The algal blooms are caused by two closely related factors.  The water is warmer than it was in the past because of climate change and the lake is shallower than it was in the past because of sediment deposited into the lake.

Black crowned night heron in algal bloom, Lake Temescal, April 2017

The park district has tried to address this issue by using various chemicals to control the growth of the algae.  Although that has occasionally been successful for brief periods of time, it is not a long term solution to the problem.  Furthermore, it is a good example of why the park district uses more chemicals than necessary.  If the park district would address the underlying cause of the problem—that is, the depth of the lake—it would not be necessary to keep pouring chemicals into the lake.  Dredging Lake Temescal should be a candidate for Measure CC funding.

And so I return to the point of this suggestion for Measure CC:  Please plan projects that take into consideration the reality of climate change, that address the underlying causes of environmental issues, and that have some prospect for success.

Thank you for your consideration.


Send your comments regarding Measure CC renewal to publicinformation@ebparks.org

Send copies to staff and board members of East Bay Regional Park District
Robert Doyle, General Manager rdoyle@ebparks.org
Ana Alvarez, Deputy General Manager aalvarez@ebparks.org
Casey Brierley, Manager of Integrated Pest Management cbrierley@ebparks.org

Board of Directors:
Beverly Lane, Board President blane@ebparks.org
Whitney Dotson wdotson@ebparks.org
Dee Rosario drosario@ebparks.org
Dennis Waespi dwaespi@ebparks.org
Ellen Corbett ecorbett@ebparks.org
Ayn Wieskamp awieskamp@ebparks.org
Colin Coffey ccoffey@ebparks.org

The consequences of dune “restoration” in coastal California

It is my pleasure to publish a guest post about dune “restorations” in Humboldt County that began about 30 years ago.  Like most “restorations,” these projects are primarily destroying non-native plants.  More often than not, they don’t plant native plants to replace the plants they destroy, although the stated goal is to “restore” native plants.

 Uri Driscoll tells us why the non-native plants were planted over 100 years ago and the consequences of removing them.  According to Mr. Driscoll’s Facebook page, he has lived in Arcata, Humboldt County since 1983.  He has had a life-long interest in outdoor recreation, horses, organic farming, and conservation.  He is a member of Arcata’s Open Space and Agriculture Committee.

 If you live in the San Francisco Bay Area, you might think these projects are not relevant to us.  In fact, they have everything to do with us because there are many similar projects here and the issues with those projects are similar. 

Bird’s eye view of San Francisco in 1868. US Library of Congress

 The San Francisco peninsula was about half barren sand dunes when Europeans first arrived at the end of the 18th century.  About 30 years ago, native plant advocates decided they wanted whatever open space that still remains on the peninsula to be returned to pre-settlement conditions, including sand dunes where they existed in the past.

These are the sand dunes in San Francisco where Golden Gate Park was built by creating a windbreak by planting trees. The windbreak stabilized the sand dunes and made it possible to plant and sustain vegetation behind the protection of the windbreak. San Francisco Public Library, historical photo collection.

Pacheco & 32nd Ave, San Francisco, 1943. San Francisco Public Library, historical photo collection

As residential neighborhoods in San Francisco were developed, iceplant and European beach grass were planted on the sand dunes to hold the sand in place.  Native dune plants are not capable of stabilizing sand for long, before strong winds move the sand beneath them.  In fact, the long term survival of native dune plants is dependent upon these disturbances. 

Trees were planted on the windward side of residential areas to protect them against the wind.  Sand on the leeward side of the trees was stabilized by the windbreak.  One of the first dune “restorations” in San Francisco proposed to destroy about 4,000 trees in the Presidio in order to restore an endangered dune plant, Lessingia germanorum.  The purpose of destroying the trees was to enable the sand to move again, ensuring the long-term survival of a native dune plant that exists only on the San Francisco peninsula.

Iceplant has been removed from several sand hills in residential neighborhoods, dumping sand on the properties at the base of the hills.  The Great Highway, which separates Ocean Beach from the residential Sunset District is often closed because of drifting sand after removal of beach grass.

In fact, everyone living on the coast of California should have an interest in the preservation of our sand dunes because they are our first line of defense against rising sea levels and the intense storms associated with climate change.  If non-native plants and trees are needed to maintain the stability of our sand dunes, so be it.  Competing agendas must take a back seat to the safety of our coastal communities.

Million Trees


Stable Dunes or Native Plants?

The North and South Spits of Humboldt County are the physical barrier between Humboldt Bay and the Pacific Ocean.  After the introduction of European beach grass (Ammophila arenaria) in the early 1900’s there has been a substantial stabilizing effect on the dunes as they grew wider and taller.  Prior to the establishment of the grass our dunes consisted of wide expanses of unvegetated, open, moving sand. This is in sharp contrast to the variety of plant cover we have today.

Humboldt Bay

In the 1980s public land managers began removing European beach grass with the goal of restoring native vegetation.  This is the story of the consequences of their projects.

Foredunes (the sand ridges parallel to and closest to the shore) with open, actively moving sands have a very high potential for accelerated erosion.  The foredunes of the North Spit and South Spit are still extremely vulnerable to accelerated erosion caused by disturbances to the vegetation.  A beach and dunes management plan and Environmental Impact Report (EIR) was developed in 1993 to address such issues.

Of greater concern, waves have washed over the foredunes on both spits where waves have breached the foredune where vegetative cover had been removed.  Repeated overwash events would significantly and immediately impact the only access road to the South Spit and the municipal water main and water treatment facilities on the North Spit.

These dunes could again be set in motion by removal of the protective cover of native and non-native vegetation.  Indeed, the intention to remobilize dunes was identified in the Conditional Use Permit application Bureau of Land Management (BLM) submitted for vegetation removal at Table Bluff County Park, a portion of the South Spit.  However, those intentions are contrary to the local Humboldt Bay Beach and Dune Management Plan and accompanying EIR.

The danger is that the South Spit’s dune topography is characterized as typically low and narrow.  With erosion and subsequent lowering of the foredune that occurs following vegetation removal, the right combination of concurrent high-magnitude seismic subsidence and wave attack could cause collapse of the land barrier between the Ocean and Humboldt Bay.  With anticipated sea level rise we would see this risk multiply.  

Source: 2008-2014 BLM monitoring report

The problem is that the previous and on-going work to remove European beach grass from the North and South Spits (in the effort to restore natural conditions and processes) has not and does not provide for the immediate re-establishment of other comparable  vegetative cover to trap moving sand and prevent accelerated dune erosion.  By not including this mandated mitigation measure, there is a real, legitimate potential for significant, cumulative environmental impact.

Why was European beach grass introduced?

The important thing to understand is that this specific type of beach grass (Ammophila arenaria) was introduced in Humboldt County in the early 1900’s.  It was done in order to stabilize dunes to protect growing communities and infrastructure. It had the additional benefit of creating extensive coastal wetlands and wildlife habitat.  By collecting sand from the beach the grass builds protective and multiple parallel ridges and accompanying deflation planes. These depressions behind the ridges act as sheltered nurseries for new plant and animal life. This process can take several decades but is reversed rapidly after the grass is removed. Such an effect has happened not only in Humboldt County but also in Point Reyes where valuable wetlands and organic pastures have been smothered by destabilized sand.

Why was European beach grass removed?

When the efforts to remove the non-native, albeit naturalized grasses began in the early 1990’s invasive biology was in its infant stages. Not much was known about the impacts from the eradication efforts of dominant species.  But to some it was important to return coastal areas to the pre-beach grass era so native plants would not be out-competed.

Every movement needs a poster child.  About this same time a cute little shore bird named the western snowy plover became just that.  Even though it is registered as a threatened species on the west coast, other parts of the country and Mexico have significant and stable populations.   We were told by local biologist Ron LaValley that the non-native grass needed to be removed to recover the local plover’s populationThis claim contradicted his original report showing plover eggs nestled in the non-native grass.  He was later convicted and sent to jail for falsifying data and embezzling a million dollars from similar projects involving the spotted owl.

Recognizing that manual eradication was very expensive and time consuming, California State Parks decided to bulldoze 40+ acres of Little River State Beach to provide plover breeding areas. Unfortunately, as Humboldt State Professor Mark Colwell noted in his 2008 report “importantly, eggs often fail to hatch in restored areas.”  This is largely because ravens and crows find it easy to locate the nests in open sand areas.

The Lanphere-Christenson Dunes Refuge director Eric Nelson determined during a 2016 Climate Ready project that the foredunes were being excessively eroded by the 25 California Conservation Corp (CCC) workers who were digging out beach grass.  His decision to spray glyphosate and imazapyr instead of hand removal was carried out despite public opposition.  It remains unclear whether, despite acknowledging excessive erosion from manual eradication efforts, the refuge will return to using that method again.

Lanphere Dunes and Mad River Slough

The public takes notice of the consequences

Some of us who live near these project areas and use them for recreation started noticing native tree mortality and changes to the landforms caused by removing the stabilizing grasses.   We started doing some initial research.  We began looking into coastal development permits, beach and dunes management plans and monitoring reports.  Our findings revealed the project areas that actually had permits also had mitigation requirements.  Those included immediate replanting and strict monitoring to make sure topography and landforms were not altered.  When we inquired about the monitoring and replanting programs we found those to be significantly deficient and in some cases non-existent.

Taking action

Our next step was to approach the various regulatory agencies.  US Fish and Wildlife Service, California Department of Fish and Wildlife and the State Water Board should be interested in the freshwater wetland infill we were witnessing.  The Harbor District and the municipal water district have a major interest in securing the two 42-inch industrial water mains protected by the same beach grass that was being removed.  The Manila Community Service District maintains a waste water treatment facility on the dunes.  We thought the California Coastal Commission would certainly want to know that these unauthorized alterations to coastal landforms were taking place. We felt sure the County planning department that issued some of the permits would take enforcement action.

The town of Manila’s water treatment facility

We brought photo and research documents from Oregon and Washington (2 and 3), made presentations and had meetings, site visits and sent email communications to no avail.

We stepped back and took a look at the board of directors for the non-profit called Friends of the Dunes (FOD) that has been promoting the grass removal from the very beginning.  They had grown from a small, broken down 400 square foot building with a net worth of about $20,000 in 2004 to 60 + acres of ocean front property with a 3000 square foot building and a net worth of over $3.4 million in 2014.  The board of directors at the time consisted of employees of most of the agencies listed above.  We understood then why we were running into so many road blocks.

Our community is well known for environmental activism.  So why the hesitation of local environmental organizations like the North Coast Environmental Center (NEC), Environmental Protection Information Center, and Bay Keeper to call out such impacts caused by bulldozers, herbicide spraying and wetland infilling?  We can only presume that the banner of “restoration” has been used as a blindfold.

Some significant successes….more to do

We have had worthy successes.  Through our efforts the California Coastal Commission has asked the Bureau of Land Management (BLM) for a new determination to address the impacts related to the Ocean Day activities involving 1000 school children digging grasses from the dunes.  So far, the BLM does not think it needs to provide that.  BLM puts on the event but the Coastal Commission bankrolls it.  We do not know yet what the Commission’s response will be to that refusal.

The town of Manila has stopped grass removal activities in its management area and has supported the planting of native pine trees (Pinus contorta, contorta) in the dunes, which we did last February.  The County planning department is engaged and acknowledges that there has been no contract with the California Conservation Corp or BLM for prior grass removal at the County Park and will not allow any more vegetation removal until a Memorandum of Understanding is developed.

The Coastal Commission has committed to reviewing the authorization allowances for BLM’s grass removal over the rest of the South Spit.  The existing Plan states a two-acre area would be subjected to grass removal strictly for monitoring purposes not the mile long area subjected to eradication to date.  BLM contends that authorization extends over the whole 800-acre Spit but have not been able to provide supporting documents.

The North Coast Environmental Center and even the Friends of the Dunes (FOD) took a position against spraying herbicides on the dunes.

Former board members of the FOD that are regulatory agency officials have resigned their director positions.

Communities around the country are hosting events to plant beach grasses like the ones that have been removed here.  Recognition of the incredible value of stabilized dunes is becoming more wide spread.  The “non-native” label is becoming more questioned.

Setting new goals and looking ahead

For us on the North Coast of California we need a much more cost effective and precautionary approach than tearing out plants that have beneficial attributes.  We need to allow the beach grass to do its job of stabilizing and protecting our dunes.  As we allow it to do that, the beach grass “declines in vigor” (4).  When that happens, other plant and animal species utilize those protections from the harsh winds and tides of the Pacific and establish heathy vibrant wildlife habitat. Our local and migratory wildlife depend on it. And so do we.

Uri Driscoll, Arcata, California


We commend the people of Humboldt County for paying attention to the damage that is being done to their public land and we congratulate them on the progress they have made to prevent further damage.  We are impressed with the methodical approach they have taken to convincing public land managers to reconsider the goals of the project and the methods being used to accomplish them. 

We wish them the best of luck with their efforts.  We are grateful to Uri Driscoll for taking the time and trouble to share this story with our readers.

Million Trees 


(1) South Spit Interim Management Plan 2002.

(2) Evaluating Coastal Protection Services Associated with Restoration Management of an Endangered Shorebird in Oregon, U.S.A.  Lindsey Carrol

(3) Sally Hacker, Oregon State University http://rsif.royalsocietypublishing.org/content/12/106/20150017

(4) The Nature Conservancy Element Stewardship Abstract For AMMOPHILA ARENARIA,  Andrea Pickart

The final episode in the 20-year saga of San Francisco’s “Natural Areas Program”

the-end-is-nearOn December 15, 2016, the San Francisco Planning commission will hold a public hearing to consider certification of the Environmental Impact Report for the Natural Areas Program. If the EIR is certified, the Recreation and Park Commission will consider formally adopting the management plan for the Natural Areas Program at the same hearing.  The Recreation and Park Commission will have the option of adopting one of the alternatives to the management plan.  The San Francisco Forest Alliance will ask that the Maintenance Alternative be adopted by the Recreation and Park Commission because it is the “environmentally superior” alternative which will destroy the least number of trees and use the least amount of pesticides. 

If you can attend this hearing and make public comment, please contact the SF Forest Alliance (sfforestnews@gmail.com) for the details about where and when the hearing will take place.  If you can’t attend the hearing, please consider sending an email to the Recreation and Park Commission (recpark.commission@sfgov.org) by Monday, December 12, 2016 (the deadline for submission of written public comments to be included in the agenda packet of the commissioners). 

We lived in San Francisco for nearly 30 years and our local park was designated a “natural area” in 1997.  Based on our experience with the Natural Areas Program, we have sent the following email to the Recreation and Park Commission.  We hope that our letter will help you write your own public comment.


Subject:  Approve the Maintenance Alternative for SNRAMP

Dear Recreation and Park Commissioners,

Since the Natural Areas Program was created 20 years ago, hundreds of healthy trees have been destroyed and over one thousand trees died slowly after being surreptitiously girdled by vandals calling themselves native plant advocates in the 32 so-called “natural areas.”  Hundreds of gallons of herbicide have been sprayed on harmless plants, many that provided valuable habitat and food for wildlife.  Trails have been closed and big signs installed instructing park visitors to stay on the trails that remain. Fences have been installed in some parks to enforce those restrictions.

This sign in a "natural area" has been altered to express the public's opinion of the Natural Areas Program. Courtesy San Francisco Forest Alliance.
This sign in a “natural area” has been altered to express the public’s opinion of the Natural Areas Program. Courtesy San Francisco Forest Alliance.

After all that destruction and restriction, what has been accomplished?  Non-native plants have been repeatedly eradicated in the “natural areas” and native plants were planted.  These native plant gardens have repeatedly failed:  the native plants die and the non-native plants return, in some cases many times.  Native trees have been planted in a few “natural areas” but most have died, despite being irrigated during an extreme drought.  After wasting millions of dollars and the associated labor, there is little to show for that investment after 20 years.

Therefore, I am writing to ask the Recreation and Park Commission to vote to adopt the Maintenance Alternative as provided by the Environmental Impact Report that was 10 years in the making.  The Maintenance Alternative would enable the Recreation and Park Department to continue to take care of the “natural areas” they have already created, but it would prevent further tree destruction, further restrictions on recreational access, and require fewer pesticide applications.

Besides the obvious lack of success of the Natural Areas Program after 20 years of effort, there are many other reasons why it would be wise for the Recreation and Park Department to quit throwing good money after bad money.  Here are some of those reasons:

  • The Natural Areas Program was predicated on the mistaken assumption that native plants are superior to non-native plants as habitat for animals. In fact, in the past 20 years multitudes of empirical studies have been conducted that prove that wildlife has no preference for native plants.  Wildlife is just as likely to use non-native plants as they are native plants.
  • The Natural Areas Program also assumed that greater biodiversity would be achieved by eradicating non-native plants. They were mistaken in that assumption as well.  Studies have been conducted all over the world in the past 20 years that find no decrease in plant biodiversity resulting from introduced plants.
  • The climate has changed since Europeans arrived in the Bay Area in 1769 and it will continue to change. The plants that existed here in the distant past are no longer adapted to current conditions.  The ranges of native plants and animals must change if they are to survive in the long run.  Therefore, demanding that historical landscapes be re-created serves no useful purpose.
  • The native trees of California are dying by the millions. The US Forest Service informs us that 102 million native conifers have died in the Sierra Nevada in the past 6 years.  University of Cambridge recently published a study about Sudden Oak Death in which they reported that 5 million oak trees have died in California since 1995 and that the epidemic is “unstoppable.”  There are SOD infections in Golden Gate Park and the Arboretum.  The US Forest Service tells us that Coast Live Oaks will be virtually gone from California by 2060.  A study of redwoods predicts that its native range will shift north into Oregon by the end of this century.  In other words, if we want trees in California, many of them will have to be non-native trees adapted to a hotter, drier climate. 
  • Environmental conditions in a densely populated urban area such as San Francisco are also incompatible with the unrealistic goals of the Natural Areas Program. The heat island effect of urban areas exacerbates climate change.  Increased levels of soil nitrogen caused by the burning of fossil fuels promotes the growth of weeds.

The Natural Areas Program was a good idea that has outlived its usefulness.  We may try to keep it alive for sentimental reasons, but expanding it would be rewarding failure.  Please adopt the Maintenance Alternative.

Thank you for your consideration.

stop-destroying-trees

Subirdia: Birds adapt to the Anthropocene

christmas-holly-4This article is our Christmas present to our readers.  We celebrate the holidays with good news about the birds living in cities all over the world.

Subirdia was written by John Marzluff, an academic ornithologist at University of Washington. (1)  He reports many years of his research and that of his graduate students about the birds that live in urban and suburban Seattle as well as surrounding forest reserves.  He also reports on countless studies of bird populations in similar settings all over the world.  All of those studies reach remarkably similar conclusions.

It took me a long time to read this book because its introduction was off-putting.  Virtually every plant and animal was preceded by the qualifier of “native” or “non-native.”  The implication of the introduction was that the most important feature of every plant and animal is whether or not it is native.  As our readers know, we consider the nativity of plant and animal species largely irrelevant.  All plants and animals are at home in our ideal nature.

Owl nesting in eucalyptus, courtesy urbanwildness.com
Owl nesting in eucalyptus, courtesy urbanwildness.com

When I finally got around to reading Subirdia I was pleasantly surprised.  Although the author has a preference for native plants and animals, in fact, his research and that of others does not justify his obsession.  Where birds are actually found in the greatest numbers is where the habitat is most diverse, not necessarily exclusively native.

Suburbia is very birdy

The conventional wisdom is that cities are inhospitable places for birds and other wildlife.  After all, haven’t we paved over much of their habitat, interrupted their movements by fragmenting their habitat, and drained or covered water resources? In fact, bird populations in urban areas all over the world are both plentiful and diverse.

After years of counting numerous bird species in his hometown of Seattle, the author of Subirdia wondered if Seattle might be unique because it is heavily forested.  After conducting similar surveys in 10 cities around the world, Marzluff is convinced that birds are successfully adapting to rapid urbanization of human society.  The urban centers of cities in North and Central America, New Zealand and Europe support an average of 23 bird species.  He found the least number of bird species (11) in Auckland, New Zealand and the greatest number (31) in St. Andrews, Scotland.

Starling in breeding plumage. Creative Commons - Share Alike
Starling in breeding plumage. Creative Commons – Share Alike

Another popular myth about the loss of bird diversity in the Anthropocene is that the globalization of human civilization produces “homogenized” nature.  That is, many people believe that bird populations may not be in decline, but there are a few hardy species that dominate everywhere.  Again, Marzluff’s studies do not corroborate that belief.  Five bird species are found in cities all over the world (house sparrows, starlings, Canadian geese, mallard ducks, and rock pigeons).  However, these ubiquitous species are not the predominant bird species he found in cities.  Of the 151 different bird species he found in the 10 cities he visited, 75% of them were unique to each of the cities.   “Homogenization is barely perceptible.” (1)

Comparing bird populations in cities with nature reserves

Marzluff also compared bird populations in cities with undeveloped nature preserves.  Once again, cities still look like good homes for birds.  He finds twice as many bird species in Ketchikan, Alaska as in the nearby wildlands along the Naha River, “a remote wilderness fifty miles away…that required powerboat, kayak, and hiking to attain.” (1)

He also visited Yellowstone National Park, a 2.2 million acre protected area within an undeveloped ecosystem of nearly 20 million acres, where he counted 26 bird species in four days.  From there, he flew to New York City where he counted 31 bird species in Central Park in only three days.  Historical records of bird surveys in Central Park and Yellowstone National Park indicate that about 200 bird species have been found in both parks since the late 19th century.  “From a bird’s perspective, a large park created by human hands or by nature is not all that different.”  (1)

Accommodating birds in cities

Marzluff’s concluding chapters advise city dwellers how to encourage and support birds.  His “ten commandments” for accommodating birds make no mention of planting native plants or eradicating non-native plants:

  • “Do not covet your neighbor’s lawn.”
  • “Keep your cat indoors.”*
  • “Make your windows more visible to birds that fly near them.”
  • “Do not light the night sky.”
  • “Provide food and nest boxes.”
  • “Do not kill native predators.”
  • “Foster a diversity of habitats and natural variability within landscapes.”
  • “Create safe passage across roads and highways.”
  • “Ensure that there are functional connections between land and water.”
  • Enjoy and bond with nature where you live, work, and play!”

Marzluff expresses a strong preference for native plants throughout his book, but his research in Seattle is inconsistent with that preference:  “The forests of Seattle and its suburbs now embrace 141 species of trees, including 30 native species and ornamentals from North and South America, Europe, Asia, and Africa.  Some are problematic invaders, but in total they provide a diverse menu of foods and nesting and roosting sites for birds.”  (1)

Why a preference for natives?

Garter snake in eucalyptus leaf litter. Courtesy Urban Wildness
Garter snake in eucalyptus leaf litter. Courtesy Urban Wildness

Another academic scientist in Washington State, Linda Chalker-Scott, directly addresses the vexing question of why public policies which mandate the use of native plants have proliferated despite the lack of evidence that they are superior in any way.  She focuses on this question:  “Do native and nonnative woody species differ in how they affect species diversity?”  Her literature search found 120 studies from 30 countries that quantified the biodiversity of birds, insects, mammals, reptiles, and other plants in woody plants and trees in urban landscapes.

The analysis of these studies reveals that “the science does not support the supposition that native plantings are required for biodiversity…it is clear that an automatic preference for native trees when planning in urban areas is not a science-based policy.” (2) The assumption that native plants are superior to non-native plants is based on these misconceptions:

  • The definitions of native and alien species are value judgments, not science-based concepts.
  • Native plants are often poorly suited to environmental conditions in urban areas, such as compacted soil and changes in the climate. Conversely, introduced plants are often well suited to these urban conditions.
  • Many introduced plants provide valuable ecological benefits. For example, they often provide food, pollen, and nectar resources during winter months when native plants are dormant.
  • Tropical milkweed is not native to California. (Asclepias curassavica) Creative Commons
    Tropical milkweed is not native to California. (Asclepias curassavica) Creative Commons

    Doug Tallamy is the academic scientist most closely associated with the native plant ideology. His claim that insects require native plants is based on his mistaken assignment of nativity to an entire genus, when only a few species within that genus are actually native.  For example, there are over 35 species of milkweed in the genus Asclepias, but only two species are native to California.  Most members of the milkweed family are useful to monarch butterflies.  It is therefore not accurate to claim that monarchs require native plants.  They have lived all over the world for over 200 years in some places where there are no native species of milkweed.

Chalker-Scott’s meta-analysis of 120 studies concurs with Mr. Marzluff:  “The published research overwhelmingly identifies diversity, structure, and function as the most important vegetation characteristics for enhancing community biodiversity…In fact, sometimes landscapes require the inclusion of exotic trees and control of natives to maintain diversity.” (2)

Doing more harm than good

Our readers know that we do not begrudge the preference of native plant advocates for native plants.  We encourage them to plant whatever they want.  We only ask that they stop destroying the plants they don’t like.  That request is based on our belief that they are doing far more harm to our public lands than any perceived benefit of native plants.  Much of that harm is caused by the widespread use of herbicides to destroy non-native vegetation.  These herbicides are known to damage the soil and they migrate in the soil, damaging neighboring plants that are not targeted.  These issues are surely a factor in the conspicuous lack of success of their “restorations.”  There is also mounting evidence of the toxicity of herbicides to bees, birds, and other animals including humans.

But there is another, equally important reason why we object to the futile attempts to eradicate non-native plants.  They are providing valuable habitat for wildlife.  Even when they are replaced by native plants after being destroyed, the animals that depended upon them are not necessarily restored to the landscape.  In fact, few projects plant natives after the eradication of non-natives.

Japanese honeysuckle. Attribution William Rafti
Japanese honeysuckle. Attribution William Rafti

A recently published study (3) of the removal of Amur honeysuckle (Lonicera maackii) is an example of the loss of valuable habitat.  The hypothesis of this study was that “invasion of urban habitats by exotic plants was the underlying mechanism driving changes in bird-plant networks.”  The study tested this hypothesis by comparing forest plots dominated by honeysuckle with those in which honeysuckle had been removed and the surrounding forest habitat replicated.  They measured nesting birds, nest predators, and nest survival.

They found that the lowest overall nest survival rates were found in the plots in which honeysuckle had been removed.  In other words, “…removal of invasive honeysuckle from urban forests did not restore network structure to that of rural landscapes.”  The authors concede, “This finding was not consistent with our original hypothesis that invasion of forests by the exotic Amur honeysuckle was responsible for the urban-associated changes in bird-plant networks.”  They conclude, “The degree to which native communities can be restored following removal of exotic plants remains unclear.” 

Actually, we think it is quite clear that eradicating non-native plants does not benefit man or beast. We marvel that the fantasy persists that there is some theoretical benefit to killing harmless plants, despite the consistent lack of evidence of any benefit and the considerable evidence of the harm of such attempts. 


*Like most ornithologists, Marzluff comes down hard on cats as killers of birds in his book.  However, he cites just one study about predation of fledglings.  The study used radio transmitters to determine the fate of 122 newly fledged birds over a period of two years.

The results do not justify the demonization of cats:  “Only 20 percent of radio-tagged birds died during our study.  Birds such as Cooper’s hawks and mammals such as Townsends’ chipmunks, ermine, and Douglas squirrels were the most likely predators.  The most notorious of all bird predators, the out-of-the-house cat, was implicated in only one death, though we could never be entirely sure which mammal or which bird had killed the fledging.”  (1) Marzluff credits a neighborhood coyote for controlling the cat population.  Frankly, that doesn’t make sense.  Chipmunks and squirrels are just as likely to be prey for the coyotes.

We have reported on similar studies which reach the same conclusions.  A meta-analysis of 8 studies of nest predators of song birds in North America used video cameras to identify the predators of 242 depredation events.  Only one of those nest predators was a cat.

We have no objection to the general advice to keep your cat indoors. (We have never had a cat and don’t plan to.)  However, we think that estimates of birds killed by cats are greatly exaggerated.  Humans seem to have an unfortunate desire to look for scapegoats and cats seem to fit the bill for bird lovers.

  1. John M. Marzluff, Welcome to Subirdia, Yale University Press, 2014
  2. Linda Chalker-Scott, “Nonnative, Noninvasive Woody Species Can Enhance Urban Landscape Biodiversity,” Arboriculture & Urban Forestry, 2015, 41(4): 173-186
  3. Amanda D. Rodewald, et. al., “Does removal of invasives restore ecological networks? An experimental approach,” Biological Invasions, March 2015