“Restoration” projects in the Bay Area are more destructive than constructive

I began studying the native plant movement and the “restoration” projects it spawned over 20 years ago when I learned about a proposal to change my neighborhood park in San Francisco in ways that were unacceptable to me.  Virtually all the trees in the park were non-native and the original proposal would have destroyed most of them.  The trees provide protection from the wind as well as a visual and sound screen from the dense residential neighborhood.  A treeless park in a windy location is not a comfortable place to visit.

The original plans would have made the park inhospitable to visitors for several other reasons, particularly by reducing recreational access to the park.  The prospect of losing my neighborhood park turned me into an activist.  I eventually learned there were similar plans for most major parks in San Francisco.  My neighborhood organized to prevent the destruction of our park and to some extent we succeeded.  However, we were unable to prevent the city-wide plan from being approved in 2006, after fighting against it for nearly 10 years.

When I  moved to the East Bay, I learned that similar projects are even more destructive than those in San Francisco,  I have spent the last 20 years informing myself and others of these plans, visiting those places, and using whatever public process that was available to oppose the plans.  The following paragraphs are brief descriptions of the projects I have studied for over 20 years.

Tree Destruction Projects in the East Bay

East Bay Municipal Utilities District (EBMUD) is the public utility that supplies our water in the East Bay.  To accomplish that task, EBMUD manages 28,000 acres of watershed land.  Like most open space in the Bay Area, the vegetation on EBMUD’s land is a mix of native and non-native species.  EBMUD destroys non-native trees which it believes to be a fire hazard.  EBMUD uses herbicides to “control” non-native vegetation, but it does not use herbicides on tree stumps to prevent resprouting.  EBMUD reports using 409 gallons of herbicide and 6 gallons of insecticide in 2019.  Of the total amount of herbicide, 338 gallons were glyphosate-based projects.  EBMUD says “minor amounts of rodenticide were applied by contractors.”

The East Bay Regional Park District (EBRPD) approved the “Wildfire Hazard Reduction and Resource Management Plan” and its Environmental Impact Report in 2009.  This plan is removing most eucalyptus, Monterey pine, and acacia from several thousand acres of parkland.  Forests are being thinned from an average density of 600 trees per acre to approximately 60 trees per acre.  These plans are being implemented and funding for completion of the project has been secured.  Herbicides are used to prevent the trees from resprouting and to destroy vegetation deemed “invasive.”

UC Berkeley clear-cut over 18,000 non-native trees from 150 acres in the Berkeley hills in the early 2000s.  UCB applied for a FEMA grant to complete their clear-cutting plans.  The FEMA grant would have clear cut over 50,000 non-native trees from about 300 acres of open space in the Berkeley hills.

Frowning Ridge, UC Berkeley, 2010

In 2016, FEMA cancelled grant funding as a result of a lawsuit and subsequent appeals from UCB were defeated several years later.  In 2019, UCB revised its original plans.  With the exception of clear-cutting ridgelines, the revised plan will thin non-native forests.  Herbicides will be used to prevent the trees from resprouting.

The City of Oakland applied for a FEMA grant in collaboration with UC Berkeley to clear cut non-native trees on over 120 acres in the Oakland hills.  That FEMA grant was cancelled at the same time UC Berkeley lost its grant funding.  Oakland has also revised its plans for “vegetation management” since the FEMA grant was cancelled.  The revised plan will thin non-native forests on over 2,000 acres of parks and open space.  The plan is undergoing environmental review prior to implementation.  Herbicide use to implement the plan is being contested.

Tree Destruction Projects in San Francisco

The Natural Areas Program (now called Natural Resources Division) of the City of San Francisco has destroyed thousands of trees in 32 designated areas of the city’s parks since the program began in 1995.  The management plan for the Natural Areas Program was approved in 2006, after 10 years of opposition.  The plan proposes to destroy an additional 18,500 trees over 15 feet tall and untold numbers of smaller trees that the plan chooses not to define as trees.   Herbicides are used to “control” non-native vegetation and prevent trees from resprouting after they are cut down.

Sutro Forest 2010

University of California at San Francisco (UCSF) began its effort over 20 years ago to destroy most non-native trees on 66 acres of Mount Sutro.  UCSF applied for a FEMA grant to implement those plans based on their claim that the Sutro Forest is a fire hazard.  UCSF withdrew the grant application after FEMA asked for evidence that the forest is a fire hazard.  San Francisco is cool and foggy in the summer, making fires rare and unlikely.

Sutro Forest with resprouts of destroyed trees. November 2019

UCSF’s plans to destroy most trees on Mount Sutro were approved in April 2018.  Many trees on Mount Sutro have been destroyed since the project was approved and more will be destroyed before the project is complete.  UCSF made a commitment to not use pesticides in the Sutro Forest.  Many of the trees that have been destroyed have therefore resprouted.  Unless the resprouts are cut back repeatedly, the forest is likely to regenerate over time.

  Tree Destruction Projects on Federal Lands

The federal government is one of the largest landowners in the Bay Area.  Golden Gate National Recreation Area (75,500 acres), Point Reyes National Seashore (28,800 acres), and Muir Woods National Monument are operated by the National Park Service.  The Presidio in San Francisco is a National Park that is presently controlled by a non-profit trust.  These parks have engaged in extensive tree-removal on the public lands they control.  Information available on their websites does not enable us to quantify the acres or number of trees that have been removed or are planned for removal in the future.  Therefore, we will describe those projects in the broad terms available to us.

There are two main categories of tree-destruction projects on these federal lands.  There are many large-scale “restoration” efforts that have required the removal of all non-native vegetation, including trees.  These attempts to eradicate non-native plants are based on a misguided belief native plants will magically return.  Herbicides are used by National Park Service to destroy non-native vegetation, although specific information is difficult to obtain because NPS is not responsive to inquiries and the federal public records law can take years to respond.

Eradication efforts fail regardless of method used

In “Lessons learned from invasive plant control experiments:  a systematic review and meta-analysis,” scientists analyzed 355 studies of attempts to eradicate non-native plants from 1960 to 2009.  The scientists determined the methods used and the efficacy of those methods.  More than 55% of the projects used herbicides, 34% used mechanical methods (such as mowing, digging, hand-pulling), 24% burned the vegetation, and 19% used all three methods.  The study found that herbicides most effectively reduced “invasive” plant cover, but this did not result in a substantial increase in native species because impacts to native species are greatest when projects involve herbicide application.  Burning projects reduced native coverage and increased non-native coverage. In other words, it doesn’t matter what method is used, eradicating non-native plants does not result in the return of native plants.   We didn’t need a study to tell us this.  We can see the results with our own eyes.

Flammability of plants is unrelated to nativity

The other, larger category of tree-removal projects on these federal lands are the so-called “fuel management projects.”  The flammability of non-native plants and trees is exaggerated in order to justify their destruction.   Native plants are not inherently less flammable than non-native plants.

In fact, native vegetation in California is fire adapted and fire dependent for germination and survival.  The California Native Plant Society recently revised its “Fire Recovery Guide. The Guide now says, “California native plants are not inherently more likely to burn than plants from other areas.”  This statement is the mirror image of what defenders of our urban forest have been saying for 25 years:  “Non-native trees are not inherently more flammable than native trees.”  Both statements are true and they send the same message: flammability is unrelated to the nativity of plants.  “Think instead about characteristics of plants,” according to the CNPS “Fire Recovery Guide.”

There are undoubtedly many other similar projects of which we are unaware.  I report only on projects that I have direct knowledge about and that I have visited.

Why I opposed these projects

The San Francisco Bay Area was nearly treeless before early settlers planted non-native trees.  Non-native trees were planted because they are better adapted to the harsh coastal winds than native trees.  The treeless grassland was grazed by deer and elk and burned by Native Americans to promote the growth of plants they ate and fed the animals they hunted.  Grazing and burning maintained the grassland, preventing natural succession to shrubs and trees.

Native Americans setting grass fire, painting by Frederic Remington, 1908

Modern land use and management policies have suppressed fire and reduced grazing in the Bay Area.  Consequently grasslands are naturally converting to chaparral and scrub.  Although managers of public lands often describe these changes in the landscape as “invasions,” Jon Keeley (Ph.D. biologist, USGS) considers them a natural succession“These changes are commonly referred to as shrub invasion or brush encroachment of grasslands.  Alternatively, this is perhaps best viewed as a natural recolonization of grasslands that have been maintained by millennia of human disturbance.” 

Early settlers planted trees to protect their residential communities and their crops from wind.  The urban forest also provides sound and visual screens around parks that are surrounded by dense residential neighborhoods.  Urban forests are storing carbon that is released as greenhouse gas when they are destroyed. They also reduce air pollution by filtering particulates from the air.

When trees are destroyed, the unshaded ground is quickly colonized by weeds that are then sprayed with herbicide.  Even environmental organizations that support the destruction of non-native trees agree about the results of these projects:

  • The California Native Plant Society predicted the post-project landscape in its written public comment on the Draft Environmental Impact Statement (DEIS) of the FEMA project in the East Bay hills with this rhetorical question: “What mechanism is being instituted by FEMA in this DEIS to guarantee a commitment of money and personnel for management of greatly increased acreages of newly created annual weedy grassland?”
  • The Audubon Society predicted the post-project landscape in its written public comment on the DEIS: “There is no support for the conclusion that native vegetation will return on its own.  This plan may not result in an increase in native trees and plants…Heavy mulching will delay or prevent the growth of native species.”

To summarize:  I am opposed to destroying our urban forests because they perform many important ecological functions, including providing habitat for wildlife.  Furthermore, the herbicides used to destroy the forest and control weeds that thrive in the absence of shade, damage the soil and create unnecessary health hazards to humans and other animals.

Engineering Eden: The contradictory mission of the National Park Service

engineering edenThe history of our national parks is also the history of land management practices in America because they are the places we have made the strongest commitment to preserve and protect.  Engineering Eden (1) tells the story of how land management practices have changed since the inception of our national park system in 1872, when Yellowstone National Park was created.  This article is based on Engineering Eden.

The law that created Yellowstone National Park contained a contradictory mandate that foretold the conflicting land management practices of the National Park Services (NPS) that are still evident today:  “On the one hand, it ordained that Yellowstone was to be a ‘public park or pleasuring-ground for the benefit and enjoyment of the people.’  On the other, its minders were instructed to ‘provide for the preservation, from injury or spoliation, of all…natural curiosities, or wonders within said park, and their retention in their natural condition.’” (1)  Several generations of NPS leadership interpreted this contradictory mandate differently.

Bears as entertainment

Initially, the emphasis was on the recreational function of the parks, as huge, elaborate hotels and visitor facilities were built.  Visitors to these remote locations had to be fed and waste management was not more sophisticated in the parks than anywhere else in the 19th century.  Huge garbage dumps quickly developed and they drew black and grizzly bears out of the forests for the easily available food.  Over time, these garbage dumps became stage shows for visitors to gather at the end of the day in amphitheaters built for that purpose to watch the bears arrive for a scheduled “feeding” at the dumps.

Bears being fed by visitors at Yellowstone National Park
Bears being fed by visitors at Yellowstone National Park

Visitors were also not discouraged from feeding the bears by hand in their campsites and along the roads in the parks.  The bears’ expectations of food from the visitors sometimes resulted in injuries:  Between 1931 and 1939 there were 527 injuries such as “slashes and bites to arms, and mangled extremities that had been holding the food” at Yellowstone.

Predator control

The US Forest Service is the sister agency of the National Park Service.  It was created in 1881 in response to a growing concern that the country was consuming its forests at an unsustainable rate.  Its mission was the creation of a forest reserve.  These forest preserves provided grazing leases to privately owned herds of cattle and sheep and the forest service took responsibility for controlling predators of the domesticated animals.

The forest service was join in this mission by the Biological Survey of the Department of the Interior, which reported in 1919 that it had “wiped out 11,000 coyotes in California, Oregon, Nevada, Idaho and Utah.  In 1917 the Survey killed 98 wolves, 1,437 coyotes, and 138 bobcats in Wyoming alone.  By 1920…the agency extended its deadly franchise to eastern meadowlarks, accused of eating oats and corn in South Carolina; robins in the cherry orchards of New York; grebes, loons, terns, gulls, bitterns, and three species of herons feeding at fish hatcheries; and mergansers that were supposedly depleting trout streams in Michigan.” (1)

In 1918, the NPS director ordered the staff at Yellowstone Park to cooperate with the Biological Survey in killing predators.  This order escalated the killing of predators at Yellowstone:  “From 1904 to 1935, 4,352 coyotes, 121 cougars, and 132 wolves were killed in Yellowstone.”  (1)

The consequences of losing predators

The loss of predators quickly resulted in an explosion in the population of their prey, particularly elk.  The growing population of elk browsed vegetation—“they gnawed on aspen saplings, stripped the bark of mature trees, chewed on conifer boughs, willows, currant bushes, and sagebrush”– turning beautiful landscapes into threadbare landscapes.  The loss of vegetation also reduced populations of beavers, pronghorn, deer, and bighorn sheep. The loss of those species had other consequences for the complex ecology of Yellowstone, such as the loss of wetlands maintained by beaver ponds.  Finally, the elk population grew beyond their food sources and emaciated, dying elk contributed to the unsightly consequences of destroying their predators.

Elk in Yellowstone National Park
Elk in Yellowstone National Park

The reaction of the park service managers to the exploding elk population was initially to move elk around the country to places where they had existed in the past.  Point Reyes National Seashore is one of the places where elk were reintroduced and the consequences there are much the same as they were in Yellowstone.  That is, the predators of elk no longer exist in Point Reyes National Seashore (PRNS) so there are now more elk there than can be supported by existing vegetation.  There is now a controversy about the fate of the elk at PRNS and consequent lawsuit that is another story and yet to be resolved.

When opportunities to move elk were exhausted they began to kill elk at Yellowstone.  Beginning in the 1930s thousands of elk were shot in Yellowstone to reduce the population.  Hunters in neighboring communities complained about these killings because they had enjoyed the overflow of elk outside of park boundaries where elk became prey for hunters.

Academic science comes to the rescue

Meanwhile, the science of ecology was taking shape.  The Ecological Society of America (ESA) was founded in 1915 and it passed a resolution in 1921 opposing the introduction of non-native species such as game fish to national parks.  ESA was quickly joined by the American Association for Advancement of Science, which issued a report in 1925 about the value of retaining “original conditions” in the national parks.   These organizations began to lobby for more scientific management of the national parks and their requests coincided with the development of the academic science of ecology.

UC Berkeley played an important role in the transition of park management policy from one that emphasized recreational uses of the parks to one that emphasizes conservation and preservation.  In 1962 Stewart Udall, Secretary of the Interior, appointed Starker Leopold to chair an Advisory Board on Wildlife Management for the National Park Service.  Starker Leopold, son of Aldo Leopold, was a member of the faculty at UC Berkeley forestry department.

The Leopold Report, as it is still known today, is now the guiding principle of the National Park Service:  “He called upon the Park Service to ‘restore or re-create’ natural processes and life communities to bring about conditions as close as possible to those that had been seen by the first Euro-American explorers.  The effect would be to display ‘vignettes of primitive America’ for the visiting public.” (1)

Painting of Yellowstone by Thomas Moran
Painting of Yellowstone by Thomas Moran

Restoring natural processes to Yellowstone

The management at Yellowstone took the Leopold Report seriously.  They set as their top priority the closing of garbage dumps at Yellowstone, based on their belief that the bears would quickly return to the forests.  They were advised by wildlife biologists studying the bears against making that change quickly without transitional accommodations such as stocking the forests with the carrion of the elk that were being killed.  Management shut down the biologists’ research project and removed tracking devices and identification tags from the bears that had been studied.

Park managers had never been rigorous in requiring visitors to keep their food in places inaccessible to bears.  The bears now associated food with humans and quickly became aggressive in seeking food where they expected to find it…in campsites, in cars, in cabins.  In some years, the situation was exacerbated by drought that caused the blueberry crop to fail.  And the exploding elk population also decimated the crop of currents.  So, the bears had little recourse for food except the human sources that had been freely available to them for over fifty years.

In retrospect, the consequences of these decisions seem entirely predictable.  There were many spectacularly grisly killings and maiming of human visitors by grizzly bears.  But as sad and unnecessary as those deaths were, it is even sadder to learn that hundreds of bears were killed by park rangers trying to keep visitors safe.  Bears that threatened people or destroyed properties such as cabins and cars were repeatedly darted with sedatives and moved into the forests.  They quickly returned to the same locations and were eventually killed by rangers.

By the late 1970s the number of black and grizzly bears in Yellowstone, Yosemite, and Glacier national parks had dwindled to the point that their extinction was predicted.

A new strategy is found

Starker Leopold continued to have a profound influence on the management of the national parks when he installed one of his graduate students, David Graber, in the management of Yosemite Park.  Graber is responsible for introducing a bear-proof food locker into the national park system that broke the bears’ association of humans with food.  Rigorous enforcement of rules that prohibit feeding bears and require use of the food lockers was also needed.  Eventually, the equivalent of this food locker was also invented for backpacking in the back country.

The author of Engineering Eden speculates that the personal quality that enabled David Graber to find a solution to a deadly situation was humility.  He describes Graber’s uncertainty about the many management decisions he was required to make as he worked on the thorny issues he faced, such as the question of where and when to conduct the prescribed burns that are considered necessary in our national parks to reduce wildfire hazards and to mimic the ecological benefits of fire.  He begged his mentor, Starker Leopold, for an updated Leopold Report that would provide greater guidance for the decisions he was making.  Leopold declined, while expressing confidence in Graber’s decisions and noting that uncertainty is inherent in “managing” nature.

A tribute to humility

We end this story with a tribute to Mr. Graber and to the virtue of humility in land management decisions.  In contrast to that humility, the Center for Biological Diversity (CBD) has applied to US Fish and Wildlife Service to reintroduce grizzly bears to California.  Grizzly bears have been absent in California since 1924 at a time when the human population was minuscule compared to the 39 million people who live here now.

At first glance, you might think CBD’s request misanthropic, given that some people would surely lose their lives to the bears.  But this would overlook the inevitable fact that more bears are likely to die in their encounters with humans.  The bears are ultimately the losers in conflicts with humans.

Humility requires that we defer to Mr. Graber to evaluate the request to reintroduce grizzlies to California.  Mr. Graber told the LA Times that, “…the possibility of grizzly reintroduction is exciting, but ultimately unmanageable.  ‘If there was a place to put them, I would be arguing very strongly to put them there,’ Graber said, ‘I’m sorry that there are so many people here.’”


(1) Jordan Fisher Smith, Engineering Eden, Crown New York, 2016

Science in the National Parks

We were so encouraged by our reader’s report about the conference of the California Native Plant Society (CNPS) that we decided to attend the conference of the National Park Service (NPS), “Science for Parks, Parks for Science” at UC Berkeley, March 26-27, 2015.  As we have reported many times, the National Park Service is heavily engaged in native plant “restorations.”  Their projects are some of the most aggressive in the Bay Area and some of the most successful, because they seem to have greater resources than other local managers of public land.  Therefore, we were curious about their assessment of those efforts.  Are they starting to have doubts, as expressed by some of the presentations at the CNPS conference?  This is a brief summary of what we learned.

The angry old guard

The keynote speaker was E.O. Wilson, the granddaddy of “biodiversity.”  He spoke of his desire to safeguard biodiversity by preserving one-half of the Earth as “protected areas” and the closely related goal to connect all protected areas. This lofty goal should be compared to the current figure of 13% of the earth which is presently protected and the internationally agreed-upon goal of 17%, according to the second speaker, Ernesto Enkerlin, Chair of the IUCN World Commission on Protected Areas.

The moderator, Steven Beissinger, Professor of Conservation Biology at UC Berkeley, asked Professor Wilson a few pointed questions:

  • “Can working landscapes play a role in conservation?” Professor Wilson said. “That is a stupid, dangerous way of looking at conservation.  Parks cannot be evaluated in terms of their value to humanity.  The natural world is valuable in its own right.  Emma Marris and Peter Kareiva of the Nature Conservancy are pushing this; they have the least experience with studying the natural world.  This dangerous thinking must be countered immediately.”  Granted, Emma Marris is a science journalist, but Peter Kareiva was an academic scientist at University of Washington for decades before becoming Chief Scientist at the Nature Conservancy.
  • “Must protected areas be devoid of people?” Professor Wilson said “Of course not.  Indigenous people might be included.”  In fact, indigenous people have been evicted from many protected areas around the globe.  Furthermore, virtually the entire population of the US is not indigenous.  Where does that leave us?
  • “Given the challenges faced by conservation, is triage necessary to prioritize projects to focus on the most important and threatened species?” Professor Wilson said with some feeling, “That’s ridiculous!  We CAN bring them all back, we must SAVE THEM ALL!”

Professor Daniel Simberloff, the well-known invasion biologist, was another speaker who believes it is necessary and possible to eradicate all non-native plants and animals in our public lands.  He also called out by name Marris, Kareiva and others for their criticism of invasion biology.  Frankly, we think these personal attacks are unseemly in the context of what should be considered a scientific debate about the most effective methods of conservation.  The moderator, Professor Holly Doremus (UC Berkeley, Boalt Hall), asked Professor Simberloff a few tough questions as well:

Most other speakers at the conference had a less sanguine view of our ability to “save every species” and “eradicate every non-native species.”  The need for “triage” was repeated in many presentations and descriptions of past and present projects were often pessimistic about the prospects of success.  Climate change and its impact on the environment was the dominant theme of the conference.

All loss, no gain

Mission Blue butterfly.  Wikimedia Commons
Mission Blue butterfly. Wikimedia Commons

The endangered Mission Blue butterfly exists only in a few locations in the San Francisco Bay Area:  Twin Peaks, San Bruno Mountain, Milagro Ridge in San Mateo County, and the headlands of Marin County.  We recently reported that the 32-year effort to restore butterfly habitat on San Bruno Mountain has been plagued by natural succession to native coyote brush that competes with the butterfly’s host plant, 3 species of lupine.  The status of the butterfly population on San Bruno Mountain is unknown because of inadequate monitoring.  Save Mount Sutro Forest has reported that the butterfly population on Twin Peaks remains very small despite repeated attempts to move butterflies from San Bruno Mountain.  We learned at the NPS science conference that the effort to restore butterfly habitat in the Marin Headlands in order to increase the butterfly population there has experienced its own difficulties.

The restoration of butterfly habitat to the Marin Headlands was controversial because about 500 Monterey pines were destroyed to make way for the lupine scrub required by the butterflies.  The pines had been planted by the military over 100 years ago.  They were heavily used by raptors during their annual fall migration through the Bay Area.  The Marin chapter of the Audubon Society was therefore opposed to their destruction.  As usual, this opposition was ignored by the National Park Service, which manages that property, and the trees were destroyed in about 2009.

NPS has been engaged in the effort to restore the habitat needed by the Mission Blue since the trees were removed.  Those engaged in that effort presented a poster at the NPS science conference which reported:

  • In 2010, NPS and its collaborators attempted to promote the growth of the 3 species of lupine required by the Mission Blue by removing all vegetation mechanically and with prescribed burns, then seeding with lupine.
  • Neither burn nor mechanical treatments resulted in increased lupine species cover after one or three years. In fact, both mechanical and burn treatment resulted in increased cover of non-native forbs and grasses after three years.

In other words, 500 trees were destroyed, which were heavily used by migrating raptors, but Mission Blue butterflies did not benefit from the destruction of these trees because efforts to restore the habitat they require have been completely unsuccessful.  This is a familiar scenario:  all loss and no gain.

Karner blue butterfly - USFWS
Karner blue butterfly – USFWS

We also heard a presentation about a 20-year effort to “restore” the habitat required by an endangered butterfly (Karner blue) at Indiana Dunes National Lakeshore.  The complete failure of that effort is attributed to changes in the climate, considered “abnormal:”

Despite advances in our understanding of habitat needs of the Karner blue, and extensive management to meet those needs, Karner numbers at Indiana Dunes have fallen more than 99% over the past fifteen years, with precipitous declines associated with historically abnormal weather in 2012. We have documented a role phenological [seasonal] mismatching between the butterfly and its host plant plays in this population decline and the sensitivity of this species to habitat fragmentation.”

One wonders what “abnormal” weather means during a time of extreme changes in the climate, which are not expected to return to “normal.”  The speaker predicted that the likely outcome for the Karner blue at Indiana Dunes is its complete disappearance and probable replacement with a different butterfly species which is better adapted to the new climate.

Reality Check

Doug Johnson, Executive Director of the California Invasive Plant Council, made a presentation about new digital tools to identify populations of plants considered “invasive:”  CalWeedMapper and WHIPPET.  These tools will enable land managers to set priorities for attempts to eradicate these plants.  Using  a thistle species as an example, he showed a map that indicated this “invasive” plant is present everywhere in northern California, but there are isolated pockets of it south of there.  These small, isolated populations represent potential opportunities to prevent its spread before it is so widespread that eradication is impossible.  This is an example of triage, which was the dominant theme of the conference. 

Oxalis in Glen Canyon Park, San Francisco
Oxalis in Glen Canyon Park, San Francisco

Mr. Johnson was recently interviewed by Bay Nature about a non-native species of oxalis, which San Francisco’s so-called Natural Areas Program has been attempting to eradicate for many years by spraying it with Garlon.  Garlon is the most hazardous pesticide used by the Natural Areas Program.  Mr. Johnson expressed his opinion to Bay Nature that it is futile to attempt to eradicate oxalis: “‘It’s not a target for landscape-level eradication because it’s way too widespread.’”

On March 13, 2015, the California Invasive Plant Council published its final reassessment of Blue Gum Eucalyptus (available HERE).  Cal-IPC has downgraded its rating of invasiveness and ecological impact from “moderate” to “limited.”  Although the detailed assessment is less than perfect, the overall rating itself is an improvement.  We are grateful to our readers who sent comments to Cal-IPC on its deeply flawed first draft of the reassessment.

In other words, the California Invasive Plant Council seems to have entered a new era of realistic expectations.  This looks like a BIG step forward to us, because if that viewpoint is adopted by land managers it should mean less destruction and less use of pesticides.

The Take Away

The old guard is unprepared to compromise their firm belief that it is possible to save every species of native plant and animal and that every non-native plant and animal must be killed to achieve that lofty goal. They defend their indefensible opinion by attacking those who are looking for a more realistic approach to conservation. However, climate change is bringing more and more converts to this viewpoint, which was best expressed by one of the plenary speakers, Hugh Possingham, Professor of Mathematics and Ecology, University of Queensland in Australia.  He was asked how his model of “ecological parks” fits with the mission of the National Park Service to preserve the parks “unimpaired.”  We paraphrase Professor Possingham’s answer:

“The Australian conservation ethic is similar to the United States’.  We yearn for pre-invasion days.  When I grew up in Adelaide we had 7.5 hectares of pristine vegetation for the entire city, which had 750 species at one time and now there are 500 species left.  It’s a museum.  It isn’t a functioning ecosystem.  So, we have got to embrace the creation of ecosystems that are not particularly natural.  However, I’ve learned that the birds don’t care where the plants come from.  Where weeds have been ripped out, bird diversity has plummeted.  I have been converted to the European viewpoint of disturbed landscapes: that is, these new plants have value.  Australia is completely over-run with non-native plants and animals.  Australians would be willing to shoot all the feral cats, but the fact is it’s not possible because we don’t have the resources to attempt it, let alone succeed at it.”

Thank you, Professor Possingham, for your frank acknowledgement of the value of new species to wildlife and your acceptance of more realistic goals for conservation in the 21st Century.


Videos of the plenary speakers are available on the conference website, as well as abstracts of posters and presentations.

Contradictory Mission of the National Park Service

As we have reported on Million Trees, the National Park Service (NPS) is eradicating most non-native trees on its properties in the Bay Area.  (see “Our Mission”)  We were therefore taken aback when we stumbled on a news report in the Martinez News-Gazette about the NPS destroying 20 redwoods at the John Muir National Historic Site, which is an NPS property.  It seems these redwoods are the victim of the confused, sometimes contradictory mission of the NPS.

Update:  The links in this article are no longer functional.  We therefore provide a new link that corroborates the statements we have made in this article:  “John Muir National Historic Site:  Strentzel-Muir Gravesite Plan”

Redwoods are, of course, one of California’s most revered native trees.   However, in this particular location, the NPS chooses to destroy them because they were not planted by Muir’s family.  Therefore, the NPS does not consider them “historically accurate.”  NPS says their mission requires that they cut them down.

Ironically, it is the NPS that planted those particular redwoods only 20 years ago.  They planted them after destroying the non-native eucalyptus trees that were in fact historically accurate because they were planted during Muir’s lifetime.  The eucalyptus trees were presumably destroyed because they aren’t native to California.  The redwood trees were planted in their place because NPS says their policies require them to replace every tree they destroy.

Are you confused by this story?  So are we.  We think NPS must be confused as well.  They seem to have several contradictory policies.  Their obsession with native vegetation required them to destroy eucalyptus trees 20 years ago.  Their policy requiring them to replace every tree they destroy obligated them to plant native redwoods.  Twenty years later their policy requiring them to adhere to the historical record has obligated them to cut the redwoods down.  Presumably, that same policy will require them to replant eucalyptus trees.  Where will they go from there?  One wonders.

John Muir National Historical Site, NPS photo

A little historical perspective

The NPS website for the John Muir National Historic Site describes John Muir as the “Father of the National Park Service.”  They also credit him with the creation of the Sierra Club and as the person who convinced President Teddy Roosevelt to create many of our most famous national parks:  Yosemite, Grand Canyon, Sequoia, and Mt. Rainier.  Is the destruction of two generations of mature trees any way for the NPS to honor its father?

The John Muir National Historic Site in Martinez is the home that was built by Muir’s wife’s parents in 1882.  Muir and his wife moved into the home in 1890 after his wife’s father died.  Muir lived in the home for the last 24 years of his life.

Muir’s daughter reported that her father bought about a dozen different varieties of eucalyptus from a neighbor and she helped to plant them on the property.  The property was planted with many non-native plants and trees, including palms that now tower over the property.  Clearly, the Muir family didn’t share the NPS obsession with native plants.  Nor did he think too highly of those who destroy trees:

Any fool can destroy trees.  They cannot run away; and if they could, they would still be destroyed, chased and hunted down as long as fun or a dollar could be got out of their bark hides, branching horns, or magnificent bole backbones.”

–John Muir, Our National Parks, pg 364

As public policy and horticultural fads lurch from one extreme to another, the trees are the losers in man’s conceit.   And those who love trees stand helplessly by, watching the destruction, powerless to prevent it, although we pay for it with our taxes.

Pt Reyes Light sheds light on eucalyptus myths and an arborist adds context

The Pt Reyes Light is one of the last bastions of investigative reporting in the Bay Area.  Following its tradition of digging deep into the actions of its biggest neighbor, the Pt Reyes National Seashore (PRNS), it has recently published two hard hitting articles about the massive destruction of eucalyptus on the properties of the National Park Service in Marin County.  This two-part article, “Myth of the eucalyptus blight,” is available here and here.

The Light reports that the Pt Reyes National Seashore is destroying between 400 and 600 eucalypts per year.  Its neighbor, the Golden Gate National Recreation Area, is engaged in the same eradication effort.  The Light repeats the PRNS justification for this destruction and reports the evidence that the justification is fabricated.  This justification is based on myths propagated by native plant advocates to frighten the public into supporting the destruction.  The myths and their negative impact on our environment are reported and refuted elsewhere on the Million Trees blog:

 There is also much new information in the Light articles, particularly in the quotes of a certified arborist from Berkeley, California, Mark Bowman.  Mr. Bowman adds context and clarification to the Light article for the readers of Million Trees.*

In response to the claims that the “shreddy” bark of the Blue Gum eucalyptus provides a fire ladder to its canopy and casts embers long distances from its great height, Mr. Bowman says,

“There are many mitigating factors such as the age and the amount of wind the trees receive which would determine how much bark litter would remain on the tree or be scattered on the ground.  In general, the bark that sheds doesn’t reach all the way to the top.  It usually tapers off before it reaches the first branches.  As a rule of thumb it tends to be most noticeable on the lower 20 feet or so of the trunk and collects around the tree base, which makes it rather easy to pick up if you are worried about fire safety.  This may be news to some folks, but there is no such thing as a maintenance free tree unless it is made out of plastic.  If you are going to purchase a home in or next to the forest, then you shouldn’t assume you have the right to cut it down; after all you do have a choice to live elsewhere if you consider that environment too extreme for one reason or another.”

Eucalyptus, shreddy bark low on the trunk, smooth bark higher on the trunk, Mosswood Park, Oakland, CA

 
As an arborist working in that neighborhood, Mr. Bowman is familiar with the area of the 1991 fire in the Oakland-Berkeley hills.  He says that the eucalypts were a casualty of that fire, not the cause of it:

“I took care of a property next door to where the fire started and, as I recall, that neighborhood on Charing Cross and Buckingham was comprised predominantly of pine and native oaks, not eucalyptus.  If my memory is accurate, then it appears the fire department could not halt the burning of native oaks, dry grass and pines located in that steep terrain in the beginning, before the fire became that inferno, so I don’t understand why eucalyptus is getting this bad rap as a fire starter.  There was plenty of blame for that tragedy to go around:  the homeowners who failed to maintain their properties; the city, county and state who failed to maintain theirs; and the fire department who failed to put out the blaze the day before.  When a fire ignites due to low humidity, hot dry Santa Ana winds, massive amounts of dry grass, shrubs and trees coupled with the steep terrain, there is nothing that is going to stop it but luck.  The fuel for that inferno had been obviously accumulating for years on both public and private lands.  I saw the smoke that day when I was driving along Grizzly Peak Blvd., and the first thing that came to mind was that ‘it finally happened.’  Anyone who worked in that area in the aboriculture and landscaping fields knew it was inevitable, and never once did I think that the eucalyptus trees were the issue; 20 years later I still don’t.  I want to state that I have no expertise in fighting fires; however  when a fire gets to the point that even homes being saturated with water burn, then obviously the trees burn too.  The fire could care less what species of tree is in its path or whether it was here before 1750 or not. The simplest and cheapest solution to this problem is for:  (1) owners of both public and private lands to maintain and clean their properties of dry grass, shrubs and leaf litter and; (2) insist that public agencies in charge of fire prevention use the laws and enforcement codes already on the books for those who fail to comply.  Let’s use a little common sense, that way the trees won’t burn.   This “native plant is superior” mentality is going to end up being a big taxpayer and/or rate payer fraud with no significant benefits and (more to the point) many guaranteed unintended consequences if this movement is allowed to come to fruition.  Grab a hold of your wallet folks.”

Mr. Bowman says that eucalyptus is no more likely to uproot or shed its branches than any other tree of comparable size:

“From a structural standpoint, Blue Gum eucalyptus has no inherent weakness on any below ground or above ground parts endemic to the species which would make it more prone to failure than any other large tree.  I have seen no scientific proof, nor do I have any hands on evidence that would lead me to believe that the cellular structure of this species is any more prone to failure from tension, torsion or compression forces than any other species.  Just because a large tree may look intimidating in the eyes of some people doesn’t mean it is dangerous, yet there are plenty of tree industry people all too happy to take advantage of that fear.  Every tree has its own individual and unique characteristics.  It is imperative when you are looking for advice to not take the word of the “Free Estimate” people you talk to without getting a second opinion.  Obtain a consultation from someone who has no conflict of interest in that they are not there to try and sell you on their service.  Removing eucalyptus or any other tree can be very expensive and sometimes completely unnecessary.  I’ve been in business for over 30 years and that experience has proved to me repeatedly that there is an awful lot of hopefully well intentioned but all too often misinformed people giving advice.  The best advice would be to consult with an arborist who does not have a vested interest in performing tree work.”

In fact, thinning the eucalypts can in some instances make those that remain more dangerous than they would otherwise be:

“Here again, there are many mitigating factors and situations which have to be taken into account but sometimes leaving them alone can be the best option.  There is no doubt that selective thinning of any tree species will reduce the fuel load in case of fire, but at the same time there is a myriad of potential unintended consequences when you undertake this approach:  (1) exposing the trees left behind to wind forces their root systems haven’t developed a resistance to, thus making them more prone to blow down; (2) introduction of wood decay organisms and parasitic fungi; (3) invasion of grasses and small understory plants that are more easily ignited, and (4) erosion of steep slopes previously stabilized by the roots of the trees.   Since I have mentioned unintended consequences a number of times, perhaps we should learn something from that old adage, ‘If it ain’t broke, don’t fix it.’”

Ironically, the PRNS staff interviewed by the Light actually agrees with Mr. Bowman that destroying the eucalyptus may not accomplish anything.  He observes that areas cleared of eucalypts are populated with shrubs that can be equally flammable:  “Just getting rid of them doesn’t necessarily solve anything.  It’s like swapping one problem for another…Even if it’s a native component, it might be less desirable.” 

So, why are we destroying these trees?  Clearly we are doing more harm than good.  The results are not less flammable.  The trees that remain are more dangerous than they were before their neighbors were removed.  And the landscape is doused with toxic herbicides. 

 Perhaps the answer to that question is in the answer to this question:  Who benefits from the eradication of non-native trees?  The chemical companies that manufacture the pesticides used to kill the trees.  The people who make their living destroying trees.  The people making their living “restoring” native plants.  The employees of the California Invasive Plant Council.  etc., etc. 

It’s a growth industry, funded by your tax dollars.  In the past two years tree destruction on federal lands (GGNRA and PRNS) has been funded by the federal economic stimulus program.  How does destroying trees stimulate the economy?  Might this money have made a more lasting contribution to our economy if it had been spent  repairing or improving our infrastructure?  


* Quotes from Mr. Bowman were made directly to Million Trees.  Not all these quotes appear in the Light articles.  Quotes of PRNS staff are from the Light.