Nativism is Hurting our Public Lands


Guest Rant by Mary McAllister

When I retired, a daily walk in the park became the high point of every day.  Soon I began to notice that trees in my local park in the San Francisco Bay Area were “disappearing.”  For the first time in my adult life I also had the time to inform myself of what was happening around me.  And so began the long, bumpy ride to learn about the native plant movement.

As in much of coastal California, there were few trees in the San Francisco Bay Area before the arrival of Europeans in the late 18th century.  The landscape was barren, shifting sand dunes, grassland and dune scrub, with a few trees found only in sheltered ravines where they were protected from the wind off the ocean and water was funneled to them by the steep canyons.  (Source)

Virtually all the trees in the San Francisco Bay Area are therefore not native to California.That immigrant status has put a target on their backs.  For the past 25 years, the native plant movement has gained ground.  Thousands of trees have been destroyed and the written plans of public land managers at the city, regional, state and federal levels have all stated their commitment to destroy nonnative trees and vegetation.  (Source)

UC Berkeley “Vegetation Management,” 2007

The loss of our trees is not the only thing at stake.  Pesticides are used to destroy nonnative vegetation and prevent nonnative trees from resprouting after they are cut down.  Because birds and other animals have long ago adapted to our nonnative landscape, they are deprived of their homes and food sources by the eradication of nonnative trees and vegetation.  (Source)

Native plants are usually planted where nonnatives have been destroyed, but because they aren’t well adapted to our changed climate, air quality, and soil conditions, they are fragile.  Fences and other restrictions on public access are required to protect the new plantings.  Even with such protections these projects are often unsuccessful unless they are intensively gardened and irrigated.  (Source)

Public employees engaged in these destructive activities are supplemented by a contingent of volunteers.  Here in the Bay Area, some of these volunteers have admitted cutting down trees on public property without authorization.  When they were caught, they started surreptitiously girdling trees, which kills them slowly.  In 2010 a California entomologist published a study which speculates that insects that are killing nonnative eucalyptus have been intentionally imported from Australia by native plant advocates.  The introduction of these pests was not legally authorized.  (Source)

Chicago has had a similar experience to ours in the Bay Area because it was also a treeless prairie prior to the arrival of Europeans.  Countless trees have been destroyed in the past 20 years, including many natives. Chicagoans are also subjected to prescribed burns which pollute the air and endanger people and property in order to maintain a treeless prairie.  The prairie was maintained by Native Americans by conducting annual burns which encouraged new growth, attracting the animals they hunted.  Without these annual burns, grassland and prairie succeed naturally to shrubs and slowly, over time to forest.  Ironically, native plant advocates depend upon the unnatural methods of pesticides and intentional fires to sustain the pre-European landscape of grassland.  (Source)

Nativism is particularly strong in Hawaii.  Their only frog, the nonnative coqui, is being eradicated though it has no native competitor.   A fruit-bearing tree, the Strawberry guava, is being eradicated.  Hawaii’s mangrove swamps have been poisoned and left in the water to rot.  According to a recently published study, the eradication of nonnative plants and trees has not resulted in the return of the native forest.  (Source)

In the State of Washington, nonnative marsh grass was poisoned with a pesticide about which little is known.  Two pesticides are being combined and no testing has been done on the toxicity of that combination in the environment.  The effort to eradicate nonnative marsh grass extends down the entire West Coast of the country.  In the San Francisco Bay Area, we recently learned that this project has had a negative impact on an endangered bird, the Clapper Rail, which had found cover from predators in the marsh grasses that have been removed.  (Source)

It has been discouraging to watch our public lands being damaged by extremist nativism.  However, we are encouraged by the recent work of scientists who are slowly dismantling the underpinnings of the nativist ideology, and the public is finally starting to react to the consequences of nativism.  (Source)


  1. It’s amazing the unreasonable measures people will go to for what is essentially a reasonable cause.

    The problem is that people like to simplify complex issues: these trees were not here before we arrived, so they must go!” As you so thoughtfully point out, there are more factors to consider. Thanks for the post!

  2. Have you ever heard a coqui frog? They’re incredibly loud at night, and their population in Hawaii has reached a surreal density due to the lack of a native competitor [or predator, for that matter]. Perhaps in the interests of compensating for their control in Hawaii, you would be amenable to having coqui introduced into your back yard? 😉

    • Yes, I have head the coqui, but only in a recording which is available on the website of the folks who do not believe it is necessary to eradicate it.

      The arguments for introducing new species are different from the arguments for eradicating them after they have been introduced. I wouldn’t advocate to introduce them anywhere. That is the decision-point when caution should be used.

      However, you might read about the means being used to eradicate the frog before deciding that its eradication is necessary. A spray of concentrated nicotine that has not been tested in the environment is being used. The unanswered question is, “Will this effort do more harm than good?”

    • I lived in Kihei, Maui for 20 years where there were several coqui frog infestations. I have heard them, often. They are no louder than the birds in the forests in NC where I now live – my sisters complain about the loud birds waking them when they are here – and can’t compete in the loud factor with the cicadas here in late summer. The noise argument is bogus and is people just being annoyed by something they are not used to.

      Also the coqui is not the only frog in Hawaii, its cousin the Greenhouse Frog, Eleutherodactylus planirostris is also on Maui in much larger numbers and likely most of the other islands. It’s call is a much quieter baby bird like chirp. Both these frogs have the same general habitat and food needs, yet you don’t hear a peep about the greenhouse frog from all the folks up in arms about the coqui. It’s as if the greenhouse frog doesn’t even exist in the islands.

      Hawaii has also long been home to the poisonous Bufo Toad. Frog, toad, it’s semantics at some point.

      Round about the same time the coquis arrived, the gold dust day gecko Phelsuma laticauda came and their numbers expanded rapidly.

      This little gecko is gorgeous. It lives in the same habitat and eats the same bugs as both Eleutherodactylus frogs. No one is Hawaii is shouting about getting rid of them.

      Should I tell you about the Axis deer on Maui that were breeding unchecked and coming into gardens I tended and beating the shrubberies to a pulp?

      • I can also mention when I went back to visit Maui in 2010 I saw that the Peach-faced Lovebird, Agapornis roseicollis had established itself in the wild in the neighborhood where I used to live.

        All this is my long winded way of saying the extreme focus on the coqui frog’s eradication just looks like blinders are being worn by some and pointless.

      • The noise argument is bogus…

        I dunno, spend a couple of nights in Hilo and tell me it’s not an issue. They are astonishing loud.

  3. It amazes me that people would kill trees because the landscape was once treeless. Especially when those landscapes were treeless because of human intervention in the first place.
    I think we have to accept that we have changed the landscape, and not strive for some primordial time when we hadn’t – what, damaged? – the environment, and instead live with what is here.
    Anyway, fanaticism should always be avoided.

  4. Damned if we do damned if we don’t. I see both sides of this with equal agreement–which is pretty much how the human race can be defined, constantly at war with itself, and that war spreads on to the planet like wildfire (the kind that does not rejuvenate prairie, mind you). It’s too late to have purely native landscapes, but it doesn’t mean we should keep plowing and paving what’s left, either. It also does not mean we shouldn’t try to have native landscapes remade, as long as it’s done in a studied, smart, careful way–the opposite to how we’ve careened across this country with manifest destiny riding our backs. Oklahoma was prairie with millions of bison, and a decade later it was almost all barbed wire farms with railroads and no bison at all. I think we owe the land SOMETHING.

  5. On my blog I’ve written a number of posts on this very thing. What blows me away is some of the lousy science being used to make these decisions and justify some of the most asinine absurd techniques. Everyone should get a clue and realise that Science is NOT necessarily the ever evolving ever self-correcting wonderful mechanism that promoters pimp it to be. Yes it can be a useful tool but more often than not has been abused and misused just like anything else in our world.

    Science for the most part is Ideological and Philosophically motivated and for the most part has been used as a power and wealth driven animal. I wrote a piece on some of the asinine habitat restoration practices which has been outdated for years but still practiced today when it comes to reforestation and tree planting. In nature there are a series of steps that must take place first before another phaze of restoration comes along to take it’s place. We’ve all seen charts and graphs showing various 1 thru 6 numbered phazes which we know actually happen out in the real world of nature when lets say a forest burns to the ground. What Scientists, motivated by impatience and Bosses who want results now not 100 years later do is try and by pass step 1-4 and jump to 5 & 6.

    In a way I get that. I’m human and have only a short bubble of a lifespan and find myself becomming impateint for results NOW like anyone else, even when I know better. Everyone should take a look at the articles written by Biologist Richard Halsey over ate the California Chaparral Institute and please appreciate many of those viewpoints, principles and standards apply to ALL ecosystems whether you at first realize it or not.

    I)’ve got a whole lot more to say here, but the Chaparral Institute is a worthwhile join for educating yourself on how the natural world really works. Yes there are handfuls of biologists etc who understand all of this, but they are drowned out by those that work for big corporations and when pinned down as to their own personal course of actions for these corporate giants, their excuse is “I was only following orders”. That excuse didn’t work for Nazis at the Nuremburg Trials and it shouldn’t work for intellectuals that should clearly know better.

  6. the Bay area…because “Virtually all the trees in the San Francisco Bay Area are therefore not native” does this mean they are being replaced with…? Shrubs and grasses? No trees at all?? I can’t imagine a park without shade from trees to sit under…

    • You got it! The “restoration” goal in the San Francisco Bay Area is grassland and dune scrub. The few species of native trees will not grow where the nonnative trees grow because they will not tolerate the wind and soil conditions that the nonnatives are tolerating.

      Also, the few species of native trees are more appropriately called shrubs. None of them will be as tall as the nonnatives trees that are providing windbreaks and other important ecological functions.

      • “The “restoration” goal in the San Francisco Bay Area is grassland and dune scrub.”

        There is no single restoration goal for the entire San Francisco Bay Area.

        Sometimes it is grassland and dune scrub, sometimes it is marshland, sometimes it is oak savannah, sometimes riparian creeks, etc. Each restoration project is particular to the location in question.

        Generalizing the restoration goals of one location to the entire Bay Area is not only incorrect, it is misleadingly alarmist.

      • “Also, the few species of native trees are more appropriately called shrubs. None of them will be as tall as the nonnatives trees that are providing windbreaks and other important ecological functions.”

        This statement simply isn’t true; there are scores of tree species native to Contra Costa and Alameda counties which very tall and tolerate wind.

    • There are many, very beautiful, trees native to the SF Bay area. We should be planting them in our public spaces and not planting trees that are native to other continents.

    • As a member of one of the chapters of the California Native Plant Society, I have to say the allegations that native plant enthusiasts want to eliminate all non-native trees in all places simply isn’t true. There might be a few radical crazies out there, but that is certainly not the stated policies of the CNPS.

      Restoration practices at a particular location shouldn’t be read as being some kind of broader crusade against trees.

  7. I suggest everyone read Emma Marris’ “The Rambunctious Garden’ for a viewpoint similar to this post and a roadmap for a more balanced way forward than nativism.

    I’m sure a lot of us have read Tallamy, which is a powerful argument against lawns and exclusively exotic plantings. However, in highly disturbed urban ecosystems the nativist quest seems particularly quixotic.

    We have had LA spending a bunch of money to eradicate tree of heaven. Money that could have been much better spent acquiring more open space or improving the land they already have. But the idea that millions are spent cutting down trees with no hope of eradication is asinine. Of course the plans for Sutro are even crazier.

    • Here, here!! By all means read Emma Marris’ Rambunctious Garden. It is a comprehensive and comprehensible overview of the latest science which is revising invasion biology. Marris has interviewed all the scientists who are working on this much needed update and she translates scientific jargon into terms that the general public will understand.

      Thank you, Emma Marris!

    • I suggest everyone read “Gardening with a Wild Heart” by Judith Larner Lowry. If you live and garden in California, you owe it to yourself (and to the California environment) to read this book.

  8. I can’t speak to what is happening in San Francisco, but I am from Chicago so I can address that point. The author is entirely mistaken when she writes that trees are being removed because the Chicago area used to be a prairie. Actually, the Chicago area used to be a mix of prairie, savannah, and woodlands. The only trees that are being removed are invasive species such as buckthorn that are choking our local forest preserves and other wooded areas. They are being removed so that a mix of other tree species can be allowed to re-establish themselves.

    • My understanding of what is happening in Chicago is based on these sources: I’ve read two books (Restoring Nature and Miracle Under the Oaks). I’ve met and corresponded with the editor of Restoring Nature for about 10 years. I’ve been corresponding with several people in Chicago for several years who are trying to save their trees, stop the prescribed burns and spraying of pesticides. I have seen photographs of piles of chipped trees and piles of logs in Chicago that are about a hundred feet tall.

      Two of the most prominent scientists whose recent work proposes a revision of invasion biology—Mark Davis and Arthur Shapiro—have used the futile effort to eradicate buckthorn in the Midwest as an example of why such a revision is needed.

      • I’m not farmiliar with any of the sources you cite. However, I can say from personal familiarity with the Cook County Forest Preserves that your assertion that conservationists/native plant advocates seek to destroy all trees in order to restore a treeless prairie is simply absurd. As I said earlier, Chicago never was all prairie, the people working on native plant restoration are aware of this, and only a tiny portion of public lands is dedicated to prairie restoration. As to buckthorn, should you come to Chicago I would be glad to personally show you the sterile monocultures it has created on public lands near my home.

      • I have to add one more point. Giant piles of wood chips and logs such as Ms. McAllister mentions could easily have been created by the storm damage and dead trees to be found in a single suburb, such as my own. It would hardly constitute scientific evidence of anything.

      • Mary,

        I appreciate the rant and all the excellent comments which have followed.

        As an ardent tree-hugger and intrepid midwestern gardner, I have to correct your dangerous misunderstanding of the problems posed by buckthorn.

        It is highly invasive, and quickly forms a dense monoculture of shrubby growth that chokes out most other vegetation. I speak from personal experience, having battled this invasive for over twenty years on two properties.

        The first property was adjacent to a large, diverse wooded preserve. As many large ash trees succumbed to the emerald ash borer, the buckthorn invasion accelerated, quickly turning large portions of once diverse woodlands into inpenetrable shrub masses.

        With much effort, I was able to hold the buckthorn at bay on the small quarter acre patch of woodland on my own property. Having recenty returned to the area 3 years later, I sadly noted that that patch of woods is now a dense, inpenetrable buckthorn shrub land.

        My current property likewise has a wooded area, and the buckthorn battle continues. Buckthorn can be contained and eradicated with effort and education of adjacent property owners. This in not a ‘harmless’ tree.

        Kudos to the Cook County preserve for making the effort to maintain a beautiful urban woodland.

  9. What’s that phrase about “The road to Hell?” We, as humans, have a singular talent for being single-minded, and not really thinking through a problem such as this. The native movement has inspired a well-deserved resurgence of native perennials and shrubs, but here on the East coast, it can lead to some awfully boring landscapes for 10 months of the year, with little foliage variation. I know I’m preaching to the choir, but even large park lands in our urban areas don’t have the same climactic conditions as the previous “native landscape” enjoyed. Forcing the issue and remaking these areas to the native condition is asking for maintenance headaches. Besides, apart from a small display garden of “how this area looked before we lived here”, who wants to go to a park with no shade trees?

    • That’s one of the major problems that I am seeing here in LA. We have Griffith park which is huge, rugged, and generally speaking the native chaparral landscape. However, in the summertime those hills are brutally hot to be in. Well, there is a major nativist lobby here and they constantly push for all new open space to be more of the same. When people really want shade and respite from our southern california heat. I wonder if they enjoy the heat and the dust and just want to keep the open space to themselves by ensuring it stays inhospitable.

    • There are plenty of beautiful shade trees native to the SF Bay area. We can (and should!) be planting them where we can.

      • I just planted two Acer macrophyllum in my back yard in San Mateo.

        They’re native to my area (although more common up the hill from the flat area where I live). A drive along Skyline Boulevard in the Santa Cruz mountains provides ample evidence that the Bay Area has many native trees, some of which are hundreds of years old, pre-dating European contact.

        I don’t know any native plant enthusiast who suggests that the Bay Area was entirely treeless, although many of the flat areas that now hold housing were tidal marshes, wetlands, and other estuarine environments long ago.

        In fact, the Santa Clara Valley chapter of the California Native Plant Society encourages the planting of more trees, and maintains a list of native trees it recommends in urban environments:

        • I”m sure there are many ways to define the San Francisco Bay Area. When describing both native plant “restorations” and the natural history of the Bay Area, I am speaking only of San Francisco and the East Bay, specifically Alameda and Contra Costa counties. The links I provide which describe both the projects and the natural history make that clear.

          I try not to generalize outside my own personal experience and the reading I have done beyond my personal experience. When I depend upon written sources, I confine myself to the work of academic scientists.

          I hope I have made it clear in both my post and my comments that I like native plants and trees and would like to see more of them. However, the arguments for planting and the arguments for destroying are very different. People should plant what they prefer. I only ask that they quit destroying the plants they do not prefer.

          • Then to avoid confusion I suggest you make it clear that you’re talking about the landscape of those specific areas, because pretty much every other definition of the Bay Area used by those who write about floristic communities and plant history encompasses far more area than just the counties you mentioned.

  10. Hmph. Global climate change means that plants will have to migrate to new regions and altitudes just to survive. I see nothing wrong with non-native plants as long as they are not overly invasive. How is this different from people? My ancestors came here in the 1600’s (on one side of the family) and in the 1800’s (on the other side of the family), so, like most Americans I’m not truly “native” either, if these native plant definitions were to apply to me or most other Americans. Perhaps we should all be eradicated just like these plants? Think about it – a person is defined as native if they born on this soil, but a plant born from this soil is not? Just because its plant ancestors came from somewhere else? Hmph.

  11. Some introduction from Garden Rant editors to this Guest Rant would have been appropriate. The reader has no information about the writer and their background.

  12. Mary introduced herself at the beginning of the post, but we can just add that in correspondence with her, she came across as a sincere treehugger who’s passionate about trying to save the trees in the public lands around SF.

    • There’s not much I can add to Garden Rant’s description of who I am. I have been advocating on behalf of the nonnative trees in the San Francisco Bay Area for about 15 years. I’ve served on committees, spoken at public hearings, written letters to the editor…the standard things the public does to participate in public discourse.

      I have no economic interest in this issue. I earn nothing from my advocacy, but the satisfaction of knowing that the public knows a little more about what is happening in our public lands. My definition of success is when fewer trees are destroyed, fewer pesticides are sprayed, and fewer parks are put behind fences.

      • Those are all worthy goals that many people support, including native plant enthusiasts.

        But I don’t understand why, in an effort to achieve those goals, you feel the need to label native plant enthusiasts as “nativist” extremists and to tell a story about a treeless past for the San Francisco Bay Area which is only factually correct for some locations.

        I don’t think most native plant enthusiasts are your enemies, especially not the formal societies. I think your enemies are municipal government bureaucrats who have been given some modicum of authority over development issues and in their zeal to prove that they’re doing “something”, to justify their existence and salaries, are taking possibly inappropriate stances on some issues. And initiating actions that they don’t need to.

  13. Well, if you follow the links to Mary’s sources (which are activist websites mostly, not from original science journals), you can get a pretty good idea where she is coming from. Since this is Garden RANT, I’ll play along and consider Mary’s rant against ripping out the trees and replanting. She is entitled to her views, and is certainly sincere.

    Having grown up in the Bay Area, I have to question Mary’s assertion that there were no large trees there before Europeans; perhaps on the land occupied by SF itself, and along parts of the coast and the Bay? Because I know many native tree species in the region that were there before Europeans came (live oak, redwood, bay laurel, alder, willow, to name a few). The Ohlone and other native tribes used the acorns of the oak trees extensively, and the bark for tanning leather. I knew areas along the coast south of SF where redwoods come right down to the coast, and they were not brought by Europeans.

    It’s hard to understand where this native replanting business is headed, given that anyone can plant anything on their own property, and private property takes up so much land in the Bay Area. Also, once upon a time there were no buildings, roadways, etc….you can see the rabbit hole that will take you down!

    Nature always seeks equilibrium and is constantly adapting to achieve it, and humans are part of nature. Whether we humans are comfortable (or can survive) with the ways in which the world changes around us, and whether we consider those ways “right” or “wrong”, is irrelevant to most of nature; a human value judgment (versus, say, a coqui tree frog’s judgment). But since our natural human inclination is to “improve” our surroundings, I seriously doubt there will ever be an end to human “improvement projects” while our species exists. Our species is unique in that we have the historical context to know what came before.

    • If you follow the links to the “activist websites” that Ms. McAllister cites, you will find that those websites are full of links and citations to original scientific papers. And you will find photos and eighteenth century drawings and explorer descriptions which confirm that San Francisco was, indeed, virtually treeless before European settlement.

      • My point about the trees pre-European is that Mary, in her zeal, claims treelessness for the whole Bay Area, not just SF. This (and the stridency of her arguments) kind of undermines her credibility for me, despite the fact that on some points I agree with her. I feel like we are in a court of law here, not sharing information or ideas…

        • Now, really, Anne. You start out by dinging Ms. McAllister for not providing enough scientific links. When I suggest you can find such links on the websites she offers, you feel like we are “in a court of law,” “not sharing information.” What information did you have in mind, if not the scientific evidence and the documentation of pre-European San Francisco? I’m puzzled because I can’t find much substantive disagreement between you and Ms. McAllister.

          • I wasn’t meaning to ding Mary, just pointing out that those of us who clicked on the link to her sources would have to read through a layer of bias before finding the original source material.

            The “court of law” comment just reflects how this dialog has felt to me. I can see that Mary and others in this dialog feel pretty passionate about the subject, which is fine. But it’s a debate that’s been going on here on the blog, and in many other places, for a long while, with little meeting of minds. Since I myself am unresolved on the issue (and feel like there is a middle ground somewhere that will eventually be driven by climate change and water issues), I tend to ask questions and think aloud from both sides.

    • I find it ironic that a tree-lover doesn’t know about the many pre-European trees in the Bay Area that are still here and centuries old.

  14. Many/most of the non-native trees being aggressively eradicated in the Bay Area by public agencies — Eucalyptus, Broom, Acacia — are species that pose a very high fire risk. The Berkeley photo shows a project motivated by fuels management rather than nativism.

    • The native landscape in California is equally flammable. Virtually any accusation about nonnative plants and trees is equally true of some native species. The claim that nonnative plants and trees are more flammable is one of many justifications that are used to convince the public that they must be eradicated. Most wildfires in California involve no nonnative trees.

      There is one important caveat to this generalization. Most species of Eucalyptus do not tolerate prolonged freezes which are rare in the San Francisco Bay Area. There were two such freezes in 1972 and 1990 which produced a great deal of dead leaf litter. The government and the public did not have the wisdom to clean up that leaf litter and it contributed to the wildfires in the East Bay in the subsequent fire seasons. The fires in California are wind driven. Everything will burn in its path, whether native or nonnative.

      There are not such freezes in San Francisco which is on a peninsula that is completely surrounded by water. The ocean moderates the climate, lowering temperatures during the summer and raising them in the winter. Yet, native plant advocates in San Francisco want the public to believe that they are endangered by the eucalypts in which there has never been a wildfire.

      Fire is the cover story for those who want to eradicate nonnative trees and plants because fear is powerful motivation.

      • Uhmm, sort of, but not really. It is true that some CA natives can burn readily. Indeed the seeds of some actually need fire in order to germinate. But most of them do not burn as fast or as hot as eucalyptus, nor are they as tall which limits the speed at which the fires can spread. (Watching those eucalyptus crowns explode into flames during the great Oakland Hills fire was truly terrifying.) And non-native grasses are far more flammable than the native bunch grasses.

        But the really big difference between CA natives and non-native with respect to fire, it the behavior post fire. Unlike most non-natives, CA native chaparral and various scrub species (including the bunch grasses) like you have throughout southern CA and the East Bay Hills are very deep rooted – that’s one of the features that gives them drought resistance. That means they will still stabilize soils even when burned to the ground. Furthermore, these plants will start to grow again after the first post-burn rain. (I visited an ecological reserve in southern CA after a huge fire and saw stuff crown-sprouting while the ground was still smoking!)

        I grew up in southern CA and am VERY familiar with the fire-rain-mudslide pattern. A chaparral or scrub landscape will certainly burn, but it won’t slide and it will recover on its own – no hydro-seeding needed.

        • This is another case in which native and nonnative plants have a lot in common. Eucalyptus is notoriously deeply rooted. It has been used all over the world to dry out wetlands. We saw a lot of eucalypts in Sicily a few months ago. They had been planted in the 1930s to dry out wetlands as a means of reducing mosquito populations and eliminating malaria.

          Likewise, eucalypts resprout when they are destoyed, regardless of the means of destruction. If they are burned by fire, they will resprout, When they are cut down, they will resprout. When they die back because of a deep freeze, they will grow back.

          Plants all use similar survival strategies, regardless of where they come from. For example, the seeds of nonnative broom survive in the ground from 60-80 years. Unless you are prepared to eradicate all that broom every year for that long, you are wasting your time.

          • You are making a very good case for the ruthless eradication of Eucalyptus! And yes, I do support the removal of broom from our wild lands. Also russian thistle. The problem is not with any individual plant, it is with the fact that these very invasive species spread quickly and crowd out everything else. So you are left with monoculture where there was once diversity. And if any of the native plants that are wiped out were an obligate food or shelter source for an endemic animal or insect, that animal goes extinct as well.

          • So which is it, Flora. Are we going to ruthlessly rip out eucalyptus because they don’t have the post fire behavior as native shrubs, or because they do have the same post fire behavior as native shrubs? I suggest you just want to rip out the eucalyptus because it’s non-native. All the rest is rationalization.

  15. As a native-born Californian and an ardent admirer of California’s beautiful and unique native plant communities, allow me to offer a defense of the impulse to restore some of California’s natural heritage, if not the heavy-handed methods with which that impulse is sometimes expressed.

    Many of these plant communities have been all-but destroyed, either directly by development or indirectly through the introduction of invasive exotic species. Most of them are never coming back unless they are actively restored. Public lands are a logical place to attempt such restoration (although, obviously, not all public lands are appropriate for such projects).

    I agree that ripping out beloved, mature trees from public parks in urban areas is not a very good idea. But neither is it a good idea to rip out beautiful, 150-year old oaks & sycamores to make way for (yet another) golf course or shopping mall. And the latter happens on a much more frequent basis than the former.

    I think we all can appreciate both man-created landscapes and wild areas. But the balance has been shifted so far against the natural environment for so long, I for one support doing what we can to restore and protect what little is left of California’s botanical wonderland.

    The problem really isn’t that the mean old native plant extremists hate parks and trees and want to spray herbicides everywhere. The problem is that there are just too damn few parks and open spaces, period. We are squabbling with each other over crumbs when we should be uniting to demand more of the loaf!

    If you love plants, and would like to see examples of some of California’s natural heritage gathered in gorgeous park settings, I heartily recommend visiting the following:
    Tilden Park Botanical Garden, Berkelely
    Santa Barbara Botanical Garden, Santa Barbara
    Rancho Santa Ana Botanical Garden, Claremont

    Once you’ve seen a 40-foot Fremontia in full bloom, alive with birds & humming with native bees, you’ll begin to understand why some of us can get so passionate about this stuff.

    Recommended reading:
    “Gardening with a Wild Heart” by Judith Larner Lowry
    “Hardy Californians” by Lester Rowntree
    “An Island Called California” by Elna Bakker

    • I am very fond of native plants and trees. I much prefer a beautiful oak to a big eucalyptus. I do not begrudge people their personal plant preferences.

      I only ask that we consider the damage that is being done when we destroy a healthy landscape. Think of the millions of tons of carbon stored in our eucalypts which could easily live another 200 years if left alone. Millions of tons of carbon will be released into the atmosphere when they are destroyed. Climate change is a more serious threat to our native plants than the mere existence of nonnative plants.

      And when the eucalypts are doused with pesticides to prevent them from resprouting does it benefit the native plants that we hope will return? Is that a risk worth taking?

      • Mary, you need to pick a different poster child for your cause. The Eucalyptus is not a tree you should be working to preserve. They burn like torches, they drop tons of leaves and branches and NOTHING grows underneath them. (I will admit that they smell very good and the wind sounds nice in their branches. But I would still enjoy them more in Australia.) A landscape dominated by Eucalyptus is a very sparse landscape offering very little for birds & insects when compared to any of our native landscapes.

        I agree that we shouldn’t be cutting down the big ones in our urban parks and all use of herbicides (not pesticides by the way) should be undertaken with great care. But preventing the spread of these trees and prohibiting the planting of new ones is a goal that anyone who cares about California landscapes should support.

        • Dov Sax (Brown University) published his study comparing the biodiversity of the oak woodland with the eucalyptus forest in Berkeley, California….your backyard I gather. He found an equal number of species of insects, understory plants, amphibians, birds, rodents, etc., in those two types of forest. It is a fiction that the eucalyptus forest is a biological desert.

          In that same study, he reports similar studies conducted all over the world where eucalypts have been planted. These studies report the same findings of equal biodiversity once those forests have existed for 5 years. Native plant advocates underestimate the ability of ecosystems to adapt to change.

          I don’t advocate for planting eucalyptus. The arguments for planting particular plants and trees are different from those for destroying them.

          • Are you referring to the paper he published in 2002? If so, you might be interested to know that he went back and resurveyed those sites in 2008 & 2009. He just published the results of that in May 2012 in an article entitled: “Dominance of non-native species increases over time in a historically invaded strandline community”

            This from the abstract: “In this historically invaded community, exotics have increased in dominance over the last decade. This change is not due solely to the success of a few hyper-dominant species, but also to the cumulative effect of small changes in distribution among many species. It remains unclear whether patterns observed are due to invasion processes that are playing out very slowly through time or to some other explanation. Our findings highlight the need for a more robust understanding of the long-term dynamics of species invasions.”

            I can’t afford the $606.00 it would cost me for a subscription to Diversity & Distribution so I am unable to read the entire article at this time.

          • Thank you for that reference. It is new to me. I will buy the article it and read it. Meanwhile, let me know point out that the abstract does not recant Sax’s 2002 findings that the eucalyptus forest and oak woodlands in Berkeley, California are equally biodiverse, which was the point I was making in quoting him.

            Here is a study, using aerial photographs of open space in the Bay Area: In “Vegetation Change and Fire Hazard in the San Francisco Bay Area Open Spaces,” William Russell (USGS) and Joe McBride (UC Berkeley) used aerial photos of Bay Area parks taken over a 60 year period from 1939 to 1997, to study changes in vegetation types. They studied photos of 3 parks in the East Bay (Chabot, Tilden, Redwood), 2 parks in the North Bay (Pt Reyes, Bolinas Ridge), and one on the Peninsula (Skyline).

            These photos revealed that grasslands are succeeding to shrubland, dominated by native coyote brush and manzanita. Eucalyptus and Monterey pine forests actually decreased during the period of study. In those cases in which forests increased in size, they were native forests of oaks or Douglas fir. In other words, the the photos provide no evidence that non-native trees are invading native trees or shrubs.

            Professor McBride also observes in this study that the vegetation changes observed in the aerial photographs suggest higher fire hazard resulting from increased native chaparral.

            Nature is dynamic. We should probably expect more rapid change in response to the rapidly changing climate.

          • I’ve bought Professor Sax’ new publication and read it. He is reporting the results of a survey of Narraganasett Bay in Rhode Island and Maryland. These were “strandline plant communities” which are shoreline areas which are said to have been “disturbed” by early settlers over two hundred years ago.

            In other words, Professor Sax was not revisiting his survey of species richness in eucalyptus forest compared to oak woodland in Berkeley in this study.

            His findings are complex and his speculation about the applicability of his findings to other settings is even more complex, so I can’t summarize them here. (You can buy the article for $35.) In any case, we can’t assume that he would have found the same results in another setting.

            That said, I would not be surprised to learn that nonnative plants may gain ground in the long term here in California, or anywhere for that matter. There is a great deal of evidence that the ranges of native plants and animals have changed because of climate change. We should probably assume that they will continue to change because society is apparently unwilling to take any action to reduce greenhouse gases.

            This is one of the great ironies of the native plant movement, in my opinion. Destroying millions of trees–which store millions of tons of carbon that will be released into the atmosphere as carbon dioxide–will contribute to climate change. Climate change is a much greater threat to native plants than any nonnative tree.

          • I have to offer a mini-rant on the new trend of referring to herbicides as pesticides. Sacrificing clarity of language – herbicides kill plants, pesticides kill insects – in the name of public relations really irks the English major in me.

            I get that the average person has a negative association to the term pesticides, and well-intentioned activists are trying to extend that cautionary approach to herbicides, but most folks resent the attempted manipulation.

            Want to make something sound really bad? Call it something else. We are awash in this kind of patronizing PR in the current political season. It turns people off.

            Call an herbicide a pesticide if you wish, but I will roll my eyes and persist in the belief that most folks are smart enough to recognize when they are being manipulated, and independent enough to resent it.

            I cling to the belief that clear language is always the better path.

          • NOB, I don’t know who you think is trying to manipulate whom.

            All the regulatory language from EPA and CEQA uses the word “pesticide” when referring to herbicides (as well as insecticides, fungicides, etc.) A few years ago I had the same reaction as you; I frequently presumed to correct what I thought was sloppy use of the English language. But I was wrong. Both the dictionary and environmental regulations say herbicides are pesticides. We don’t get to design the English language to suit our preferences. (Otherwise I would launch into a loooooong list of “corrections” that need to be made.)

        • “burn like torches” “NOTHING grows underneath them”
          The two most common myths about eucalyptus. Both are false, unsupported by evidence, but repeated ad nauseum.

        • Flora, as a lover of all trees I support fremontia and oak as well as eucalyptus. But you’re mistaken about eucs not supporting bird and insect life. They’re an extremely important habitat species because they flower at times other things don’t. Bees, butterflies and other insects depend on their nectar; all kinds of birds glean insects from their leaves. Without non-native trees, San Francisco would have a fraction of the species of birds it has now – because it would essentially have no trees.

          A lot of myths have been spread about eucalyptus.

          • It is unfortunate that so much of this discussion has concerned eucalyptus; myself being one of the culprits. I am aware that mature eucalyptus forests do provide habitat food for many birds and insects (although they can be problematic for others). I am not in favor of clear cutting mature, healthy stands in the interest of fire protection and I am certainly not in favor of the wholesale use of herbicides in our parks and wild lands – especially because the folks applying them often do not use them properly. I went to UC Berkely as an undergrad and have very fond memories of the big eucalyptus grove adjacent to the old Life Sciences Building. So, just to clarify: I am not anti-tree or anti-Eucalyptus and I am sorry I came off that way.

            However, I do disagree with the original poster and some of the commenters here insofar as I do think that the efforts to restore some of California’s native plant communities are very worthwhile and are not quixotic, hopeless causes carried out by irrational fanatics. I think in some circumstances removal of eucalyptus stands in the East Bay hills may be reasonable if the end result is a healthy, thriving, restored coastal scrub or oak woodland community. I would not support removal of a eucalyptus stand if the result will be an open field filled with annual grasses and invasive weeds. I far prefer eucalyptus to fox tails and scotch broom.

          • “went to UC Berkely as an undergrad and have very fond memories of the big eucalyptus grove adjacent to the old Life Sciences Building.”
            Aha! A point of complete agreement.

      • I must emphasize that in my comments I am not expressing a mere fondness for a particular plant or as you put it, a “personal plant preference.” I am expressing the profound desire to see the endangered native plant COMMUNITIES of our beautiful state preserved and when possible restored.

        What happens when your “personal plant preference” wreaks havoc on the natural environment? There are now miles along the coast in Sonoma and Mendocino Counties that were once healthy, diverse, communities of coastal scrub, alive with endemic plants, birds and insects now covered with nothing but Pampas grass and scotch broom. All because of some local landscaper’s “personal plant preference.”

        Just as the improper use of herbicides can have unforeseen consequences, so can the introduction of a seemingly innocuous plant or animal species. Ask a mid-westerner about bind weed or a southerner about kudzu.

    • “rip out beautiful, 150-year old oaks & sycamores to make way for (yet another) golf course or shopping mall”
      That is not the alternative to ripping out healthy non-native forest–a false dichotomy, and an attempt to make defenders of trees appear to be spoilers of the environment.
      Leave the oaks and sycamores alone; leave the beautiful 150-year old eucalyptus alone as well.

  16. Well said.
    It is sad that native plant restoration is now seen as appropriate for public spaces and not in everyone’s garden.

    • Native plant restoration is very much appropriate for private gardens! Your local native plant society can give you all the information you need to get started. (Why do you think it is “sad” that native plants would be restored in public spaces?)

  17. Is Ms. McAllister really suggesting that California fire prevention officials are engaged in a conspiracy to destroy exotic trees in order to further their true agenda of native plant restoration? I had no idea our nation’s fire departments were full of such rabid environmentalists.

    • Fire prevention officials are not advocating in the destruction of eucalyptus in San Francisco. That comes from the native plant advocates in the (so-called) Natural Areas Program in the Recreation and Park Department. Fire officials not involved.

      The University of California San Francisco applied for a FEMA pre-disaster hazard mitigation grant to remove eucalyptus from Mt. Sutro in San Francisco. Their project was native plant restoration in nature, but they claimed fire hazard. FEMA asked for 1) evidence that there was a fire hazard on Mt. Sutro, and 2) evidence that clearing the eucalyptus would reduce that fire hazard. UCSF had no such evidence and withdrew their application. San Francisco fire officials were not involved, did not support, the bogus application.

      • Skeptic is right. In fact, FEMA spoke with someone at CALFIRE about the fire hazard from eucalyptus in the Sutro Forest. All of San Francisco’s forests are classified as a “moderate” fire hazard – CALFIRE’s lowest rating.

        A massive tree removal is planned for Mount Davidson (1600 trees) – another forest that depends on summer cloud moisture. It is likely to have similar negative effects.

        The removal of non-native trees is ideological, not practical or beneficial.

  18. Ms. McAllister is setting up a straw man when she refers to “extreme nativists.” IRL, the motivations for taking specific actions are complex. Government agencies don’t do good PR/education when they embark on projects that are highly visible. So people see big trees being cut, or monocultures being cleared, and they freak out.

    I know of at least one exemplary project in the SF Bay Area: the restoration of Sausal Creek. It was a dump, with lots of invasive plants and garbage. But people would walk there, since it was the closest thing to wild nature in their neighborhood, and when they saw big trees being cleared out, they made noise. In their wisdom, the Friends of Sausal Creek invited neighbors to their meetings and work days and explained that what they had in mind would make it a better place. The result was more hands to help out, and a great way to spread the word about what was really happening, neighbor to neighbor. The invasives and garbage were replaced by all native plants, simply because they require minimal long-term care and support a wider variety of the native fauna, and today it’s a beautiful and well-used haven, and safer to boot.

    The proliferation of nonnative monocultures is a real problem. But to say that it’s impossible to eradicate it all so don’t do anything is silly. Ceding defeat without trying to do anything is tragic. The Bradley Method, for one, has been successful in restoring native-plant communities around the globe. Concerted work by volunteers (and no herbicides) has successfully reduced weed-infested areas at Edgewood Park in Redwood City. It is possible to take care of what you care about.

    • It’s good news that you are not using pesticides in Sausal Creek. That’s particularly important in a water shed, where the water can spread contamination.

      In contrast, the so-called Natural Areas Program in San Francisco has sprayed a park with a creek running through it, many times and its water shed even more frequently. Here is a recent article about the use of Milestone in that park:

      Milestone (active ingredient amino-pyralid) is known to be mobile in the soil and it does not biodegrade. For these reasons, the State of New York has banned its sale because of concerns about poisoning ground water. Milestone has also been banned in the United Kingdom.

      Despite these concerns, the Natural Areas Program has sprayed this pesticide on sweet peas in this park. We pointed out to the Department of the Environment that sweet peas are not classified by the California Invasive Plant Council as invasive plants and therefore, according to the city’s IPM policy they should not be sprayed with this pesticide. The Department of Environment responded that they have the right to call any plant they want “invasive.” Ironically, this is the same Department of the Environment that is legally committed to following the Precautionary Principle.

      This is just one small example of why these projects are controversial. Again, thank you for not using pesticides in Sausal Creek.

  19. I have a hard time taking a strong stance on either side of the issue. largely because I don’t know the science well enough and I don’t really know the goals and methods of the two sides. Global warming will make such dramatic changes over the few decades that I think it’s a fool’s errand to predict which plants will work well together or not. Plants which were not invasive before may become so, and vice-versa.

    I think a couple of things are clear: we are well into a great mass extinction, and biodiversity should be a major goal. Also, trees are being lost to a variety of human-caused changes. The more trees, the better. Those of us who garden can contribute these things. The more we learn and experiment the more likely will somebody have a solution to a particular problem in a particular area.

    At least both sides here are passionate about the best way to save the Earth, rather than all those annoying political arguments other folks get worked up about.

  20. Christoper C NC: My gosh I agree with you! Just because something was nor created in the spot where it lives does not mean it is invasive.

    However I propose we take the non natives a step further. All the idiot Kool-Aid drinkers who want to rid an area of non natives should first rid themselves. After all we are the ones destroying this land that we do not come from correct?

    The TROLL

  21. Hi Everyone, Hi Mary,
    As upsetting this article seems. I always think it is a good thing to hear the other side of the story. I would love to hear participants and rangers in the San Francisco Bay Area. Before getting agitated, why not offer these ‘public engineers’ some space in this blog and get full picture.
    Don’t forget there are a lot of rangers and volunteers that are offering time and work for a cause that they consider worthy. Let us try to understand each other and keep the environment a collective cause.

  22. I like diversity and am willing to accept that my favorite plant might be another man’s weed. Perhaps it would be better to focus on accommodating each other so that public lands ARE public. Then we could probably agree about harmful and non harmful methodologies.

  23. Great Rant and discussion thread! Obviously, from what I have written above, I disagree strongly with some things that have been said. But the whole back-and-forth has been so civilized.

  24. Like Skeptic, I too have appreciated the thoughtful and measured nature of this discussion. I think many of us have more common ground than might be discerned from the individual comments and replies. I think these discussions are very important and as such it is vital that we keep the discussion civil.

    I think the native plant enthusiasts should accept the principle that non-native plants are not “bad” in and of themselves. They are only “bad” if they pose threats to the natural environment because of invasiveness (pampas grass) or because of cultural practices (heavily watered, fertilized and pesticided lawns). We should also accept the necessity of having different standards for urban areas and actively used parks than we do for wild or wild-adjacent lands. The planting of fast-growing shade trees and turf lawns is perfectly appropriate in urban parks. Not so much in places like the Marin Headlands.

    But those on the “other” side should be willing to concede that efforts to restore native plant communities are not nefarious efforts to ruin public parks but are well-intentioned efforts to restore a bit of the local ecosystems that have been lost. Nor are these efforts futile and doomed to failure; there have been many successful efforts to restore and enhance native plant communities throughout the USA and around the world. And perhaps refrain from using the pejoratives “nativist” and “nativism” when referring to advocates for native plant restoration. These terms evoke the specter of white supremacy and racism and are not appropriate labels for folks that disagree with you about land use.

    And I think we can all agree more plants and less concrete benefits us all, human and non-human alike.

    Cheers everyone. I’ve got to go outside now and work in the garden!

    • Holy amen. What really irks me are those terms “nativist” and “nativism.” Watch out–once you put an ism on the end of a word you’ve got trouble. And a wikipedia entry. “Nativist” sounds like “atheist.” Anyone else? What’s the opposite? Foreignist? Wasn’t that a rock band?

      • OK then, guys, propose an alternative. I often use “native plant advocate” and “native plant enthusiast,” but both become a little cumbersome, especially in a discussion where they have to be repeated several times. “Nativist” seems an accurate, descriptive contraction which gets right to the issue. I don’t believe it’s the “-ist” part that bothers Benjamin; I suspect he doesn’t object to words like “ecologist,” “environmentalist,” “geologist,” etc.

        Wait, wait, before you start typing–There are a few words that “nativists” try to use to distinguish themselves from those of us who object to what we consider ill-informed and destructive practices in our public lands. These I will *not* accept.

        So please don’t suggest:
        “environmentalist” — The political battles over practices in our parks are between and among environmentalists. I have been a member of Sierra Club, Audubon, and Nature Conservancy perhaps longer than you have been alive.
        “ecologist” — Suggests that you have science behind you and we don’t. You may believe that, but I know it to be not true.
        “naturalist” — see above
        “park lover”
        “nature lover”

        I understand your concern about language used to describe you that you find offensive and/or inaccurate. Common language used by “nativists” in San Francisco to identify me includes: “nature hater,” “chemical crazy,” and “too profoundly ignorant of natural processes to argue with.”

        I don’t use “nativist” to be offensive; it’s only an attempt to use concise and accurate language. So what word should I use?

        • “Environmentalist” is a political word–it’s too vague, too charged. “Ecologist” seems too narrowly scientific and abstract. “Naturalist” seems closer to a good word. “Tree hugger” implies intimacy that one hopes will “go further.” I also hear a conflict with the word “nativist” which, to me, echoes “Native American.” This may be the product of far too much education, but tossing around the word “native” with any sent of letters after it makes me think about subjugation, forced relocation, slaughter, the eroding of culture. Which I think is what we’ve done to plant culture, along with other human cultures. Is restoring a forest or prairie on par with reparations? So I have no concrete suggestions for a new term. There ya go.

  25. One of the larger points of this Rant seemed to be that the ideological fervor of “nativists” is preventing them from making reasoned judgements. But I found this point hard to buy simply because Mary’s rant was so ideological as well. The sources were activist sites who link old studies.

    I think you need to present the latest research on the value of preserving nonnative more clearly than you did here. Your sources were not at all convincing.

    A great thread though.

    • I assume that’s a typo and you meant, “the value of preserving native.”

      So “old studies” are “not convincing” because they are not “the latest research.” ??

      One of the “old studies” that is linked and discussed on the milliontrees site is Dov Sax’s study in the Berkeley hills that showed eucalyptus forest was just as biologically diverse as oak-bay forest. This study directly contradicts a central tenet in the “nativist” (sorry) mantra: that eucalyptus forest is a “biological desert” and “nothing grows under eucalyptus.” Do you have a later study that refutes Sax’s study? If so, I would like to see it. A commenter way up this thread suggested that Sax had revisited the sites and may have altered his conclusions. Not true. The later study was done on the east coast and had nothing whatsoever to do with diversity (or lack of) in eucalyptus forest.

      I have used the Sax eucalyptus study often in discussions like this. “Nativists” simply don’t respond. Once, in years of discussion, a person suggested that the organisms Sax found in the eucalyptus forest were just passing through on their way to the oak forest. Hard to imagine how that applies to the plants on the forest floor, and pretty lame when applied to the invertebrates in the leaf litter.

      So, the old studies vs. later studies argument is hard to deal with when we don’t know what later studies you have in mind. My impression from general reading in the field is that scientists’ later studies are actually moving away from the earlier assumptions of “invasion biology.”

      Finally, for now, if the issue were “the value of preserving native” we wouldn’t be having this discussion at all. I haven’t heard anyone object to preserving existing native plants. The objection is to the wide-spread destructive activity in intact and functioning non-native habitat.

      • Skeptic,

        Are you Mary using a pseudonym? It’s very confusing, you’ve almost assumed her persona. Or perhaps you just share similar views. It’s hard to know who I’m addressing.

        Anyways, I wasn’t claiming that Sax’s 2002 study was erroneous because it’s old. I just dint think it supports the generalizations you make. It compares tue biodiversity of one eucalyptus stand vs some kind of native oak forest. So that one example shows the value of some non-native landscapes, but that does not mean that all native restorations on public lands are misguided.

        It is not clear from your article what these ecologists are trying to restore the public lands to? Are you sure that restored ecosystem will be less biodiverse than the non-native trees? And biodiversity is not always the goal of a restoration. Sometimes the goal is to re-establish some rare, uniquely regional ecosystem that has value to specific, perhaps endangered flora or fauna. Even if it’s slightly less diverse than a landscape of mixed exotic and native vegetation. While eucalyptus forests may indeed have some value, it’s not like they are rare.

        We all have a lot to learn about the value of native and exotic plants interactng in complex ecosystems. But taking one study in evaluating the biodiversity of one specific ecosystem does not mean all invasive removals are bad. And it certainly does not prove that “nativists” (whatever that means) are destroying public lands. Those kind of generalizations made this unconvincing to me.

      • Iirc, there are more recent studies presented in Emma Marris’ book supporting the studies presented here.

      • Thomas, I am a male. I presume Mary is female. I find her Rant refreshing and well-informed. You are free to disagree.

        To the more substantive part of your reply: It is clear you haven’t read the Sax study. (“one eucalyptus stand”…”some kind of native oak forest”) So of course it didn’t convince you of anything. Go ahead and read it; it won’t hurt you; and it won’t force you to give up any of your cherished beliefs. It’s just more information to consider.

        “evaluating the biodiversity of one specific ecosystem does not mean all invasive removals are bad” And no one made any such silly claim or implication in this thread. You were questioning the citations on the sites Mary linked, and implying that more recent studies would refute them. I mentioned *just one* study on a site linked, which I think contains useful, and not widely known, information. You reply with no countering study, nor indeed any study at all. So we still don’t know what you do “find convincing.”

        • Dear Skeptic,

          I read Dov Sax’s student thesis cover to cover. I do not dispute his findings. Here’s my problem: the claim that was made is that “nativism is hurting our public lands.” That’s an incredibly sweeping generalization. So I clicked through all of Mary’s sources. The backup to this claim is either some activist website (“Death of a Million Trees”!!!). Or in another example, the source Mary cites for her Hawaii example has two other articles on its page citing how introduced species are damaging Hawaii’s ecosystem.

          I don’t have any “cherished beliefs” I’m defending. I have no doubt that in some cases, exotic vegetation has a worthy ecological function; in others, it should be removed in favor of native vegetation. I don’t know whether the eucalyptus-huggers are right or wrong. There are plenty of studies that support the idea that exotic vegetation damages native ecosystems (ironically, Mary included some in her links). Here on the east coast, Douglas Tallamy’s studies of Lepidoptera show that alien exotics support little to no insect herbivores, while native flora supports an abundance. The bottom line is that no one narrow study (and Dov Sax’s study is a NARROW study) can support the ideological conclusion that Mary makes: that nativism is hurting public lands. Nor can any one study show that all invasives should be removed. It’s much more complex than that. We need more research, more studies, and for crying out loud, less ideology.

          My bottom line: too sweeping a generalization, too shoddy sourcing, too ideological a bent. I remain unconvinced.

        • No single study ever proves anything. That’s just not the way science works. But now you have more information in the back of your mind for the next time a compatriot reminds you of the “well-known fact” that “nothing grows under eucalyptus–it’s a biological desert.”

          • You are free to disparage and ignore anything you find to be an “inconvenient truth.” But you are wrong about Sax’s paper. He, with others, collected data while Sax was an undergraduate at the University of California, Berkeley. However, the paper was published in 2002, after he had received his Ph.D. in 1999. The paper was published in a refereed scientific journal, Global Ecology and Biogeography. Hardly an undergraduate paper.

            Sax also reviewed the literature on the topic and reported that other researchers around the world found the same phenomenon that he had found: Eucalyptus forests around the world are as biologically diverse as nearby native forests. The exception he reported was for eucalyptus forests that had just been planted–not much living there. But for those eucalyptus that existed for more than 5 years–they showed the same diversity as neighboring native forests.

  26. This rant feels a little off to me. I understand that people get very upset when you cut trees down. However many of the arguements seem to come from a emotional, rather than logical place.

    First off the bay area, and outskirts are still surrounded in beautiful oak woodlands and grasslands (unfortunately at risk from overgrazing and invasives)

    Most scientists and native plant enthusiasts understand that the real invasives actually change the ecosystem they live in so that other plants and animals cannot survive there. Native plant people love plants. Most of them do not limit this love to plants from one state, by the way.

    Just to put this out there, there are many groups and individuals including myself, working on restoration of californias native landscapes that do not use herbicide. There is some evidence that organic weed control works just as well or better in some cases.

    I think it’s great to promote better restoration practices, but if you want to be angry at someone, please
    consider the massively higher doses of herbicide used in your parks, farms and homes that travel into streams oceans and lakes in California. Consider your irrigation systems and the irrigation in city parks and freeways watering trees that wastes our most precious resource- water. Consider all the fertilizer running into streams from the lawns and gardens and farms. If pollution is what you are concerned about, you can start in your own backyard and kitchen.

    • But you are setting up a false dichotomy. Just because a plant is exotic doesn’t mean that it requires greater amounts of water, fertilizer, or the use of herbicides. Just because something is exotic doesn’t mean it is invasive. Just because a plant is native doesn’t mean it can get by in the particular location without supplemental water or fertilizer. Invasive plants like pampas grass are invasive by the coast, but inland, not so much. There is much more room for nuance in the discussion.

    • Plus, it’s also disingenuous to make claims of increased water and fertilizer use in the context of invasive exotics because by their very nature, invasives are invasive because they are adapted to local rainfall and nutrient amounts.

  27. SKR, as an ordinary gardener in a state suffering from one of the worst droughts in recent memory, I can give the following anecdotal evidence to your “exotics v. natives” water/fertilizer comment:

    I have non-natives, native cultivars, and natives, wilting most to least in that order. Ditto need for fertilizing. I suspect most gardeners would voice similar observations.

    Yes there are always exceptions.

    Invasives, by definition, are tough-as-nails hard-to-kill plants that thrive under local conditions.

  28. I agree with Rachel in #28: “if you want to be angry at someone, please
    consider the massively higher doses of herbicide used in your parks, farms and homes that travel into streams oceans and lakes in California.[etc.}” It’s not people who advocate for native plants and native critters who are using the most herbicides. So here’s an idea for what to call the groups you’re ranting against: herbicidists. It’s accurate and descriptive.

    And if you think you can’t fight the pesticide-industrial complex, think again. Several Canadian provinces have banned the sale of weed-feed products and selected pesticides, especially cosmetic herbicides. I stay away from my local Home Depot because it reeks of pesticides; but Home Depot in B.C. voluntarily stopped selling pesticides! If you want to wage a campaign that will have far-reaching consequences, get your town or state to ban pesticides. Again, it has been done, and though of course the herbicidists are not happy (or compliant), the reduction in the poisoning of air and water has been salubrious for Canadians.

  29. I just talked with my husband, who is a WAF&W scientist. According to him, along with being invasive, the reason Spartina is being eradicated is because it takes over entire bodies of water, trapping sediment. Over time, this can turn bays into valleys. Yes, this may be part of the natural progression of things, but it also severely affects not only the environment, but the livelihood of an entire area.

    This isn’t saying that I agree with the spraying, just that I agree that in this case at least, something needs to be done.

    Also, apparently they tried pulling it out first, only to discover that this just encouraged it to spread more.

  30. Yes, that is one of the justifications for eradicating nonnative Spartina. However, there is considerable evidence that such invasions have not occurred.

    Spartina alterniflora has been here in the San Francisco Bay for over one hundred years without blocking the many streams that feed into the bay.

    And here is a link to a video in which a scientist who studies this species of Spartina shows other examples of places where Spartina has existed for long periods of time without causing problems:

    There are many arguments used to justify these destructive projects. Most do not stand up to scientific scrutiny.

  31. Rachel and Gemma said it best: “if you want to be angry at someone, please
    consider the massively higher doses of herbicide used in your parks, farms and homes that travel into streams, oceans and lakes in California [etc]”.
    This is the best thing to come out of all this discussion. Let us join forces and work toward putting an end to herbicides and other pesticides.

    • In the San Francisco Bay Area, more pesticides are used in our public parks for the purpose of eradicating non-native plants than for other purposes. And the pesticides used for that purpose are also more toxic than those used for other purposes. Other entities are not using triclopyr or imazapyr or amino-pyralid. One of the golf courses in San Francisco uses no pesticides at all.

      In 2010, the East Bay Regional Park District reported that pesticide use for the purpose of “resource management” increased 350% over the previous year. “Resource management” is a euphemism for eradicating non-native plants.

      in 2011, the San Francisco Natural Areas Program increased the number of sprayings on non-native plants over 300% since 2009. Its pesticide use in the first 6 months of 2012 has doubled compared to the same period of the previous year.

      Since we live in an urban area, we are appropriately concerned with pesticides being used where we live. Although we are also concerned with pesticides being used in agriculture, we aren’t walking our children or our pets in agricultural fields and we can reduce our risks by eating organic foods.

      Since all politics are ultimately local, we are in a better position to influence local decisions being made in our parks than we can in a globalized agricultural market.

      We are very familiar with this particular argument. We hear it all the time. It is no consolation to us that more pesticide is used elsewhere. In fact, that is a strong argument for reducing pesticide use where we can.

  32. What is the real object of this rant? “Nativism” or some unfortunate restoration practices? Do you realize that most “nativists” abhor the use of pesticides as much as you do? Can’t you see that many choose to concern themselves with prevention, precisely because restoration is such a frustrating and thorny issue? Why are you painting all nativists with the same brush? Do you know that most pesticides are used to protect non-native plants (crops, ornamentals) rather than to destroy them and that the conservation movement keeps trying to come up with biocontrols and other forms of non-chemical control? Why are you alienating a large sector that might be interested in supporting your efforts?

    You would do well to inform yourself better about the objectives of those who try to preserve native ecosystems. Then you may find ways of working together at least in certain endeavors. It is obvious that you love nature and are deeply committed to help the environment. I hope that you realize that the same is true of those you call “nativists”. Myself, I love all creatures, even Japanese beetles; so I call myself an “ecosystem lover”. The nativist label doesn’t fit me at all. This is similar to Flora’s “desire to see the endangered native plant COMMUNITIES (…) preserved and when possible restored.”

    • I agree.

      Instead of a rational discussion about the pros and cons of restoration practices at a particular location, the rant implies that tree removal is somehow standard policy across the Bay Area as a whole, and that there is widely-supported desire or official doctrine among native plant enthusiasts to remove all non-native trees.

      Neither one of these is true.

  33. I don’t know what “nativists” this article refers to, but the California Native Plant Society (of which I’m a member) has their policies and positions available online, including those for trees.

    List of all policies:

    Policy on tree planting:

    Note that the CNPS tree policy goes so far as to allow for the planting of non-native, non-invasive trees if the conditions aren’t appropriate for natives, stating:

    “6) If the first five conditions cannot be met, but a significant advantage can be claimed through the planting of a non-native species, then only non-invasive species should be used.”

    This is a far cry from the radical motives attributed to native plant advocates in this article.

  34. In the past 15 years, many attempts have been made to have a “rational discussion about the pros and cons of restoration practices” in San Francisco and the East Bay. Occasionally these discussions have made small improvements in the plans, with respect to reducing the use of destructive methods. In one case, a suit saved a few trees in an isolated area in the neighborhood of those who paid for the suit. And we continue to try to engage the managers of these projects in a “rational discussion.” Alerting the public to what is happening on their public lands is one means of motivating a “rational discussion.”

    As for whether or not these projects are “standard policy,” I have provided links to detailed descriptions of specific projects and there are also links to the written management plans for most of the projects. So, the accusation that I am generalizing is not appropriate. Anyone with a sincere interest in where these projects are being implemented can inform themselves. I was given a word limit that prevented me from being more specific in the article itself.

    Although I speak only of those projects of which I have personal knowledge by both reading the plans and watching the implementation of those plans, there are many other similar projects all over California. I have corresponded with people in Santa Cruz and San Diego who are trying to save their non-native trees. And with a daily Google alert, I have learned of similar projects in San Luis Obispo and Los Altos.

    Much like the argument used earlier in this thread that more pesticides are used by agriculture and therefore people should not be concerned about pesticide use in their parks, the argument that this is not happening everywhere is no consolation to those who are losing their trees. I’m glad to hear that this is not happening everywhere, but that doesn’t motivate me to accept the destruction of the trees in my neighborhood

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