“Restoration is just horticulture dressed up to look like ecology”

Peter Del Tredici was invited to speak at a conference sponsored by the Presidio Trust in San Francisco, “Bridging the Nature-Culture Divide Conference by the Cultural Landscape Foundation,” January 23, 2015.  Professor Del Tredici recently retired as senior research scientist at Harvard’s Arnold Arboretum after 35 years of service.  He is an Associate Professor in Landscape Architecture at the Harvard Graduate School of Design where he teaches courses on soils, plants and urban ecology.  He advocates for a pragmatic approach to urban landscapes, which values novel ecosystems for the functions they perform and their sustainability in stressful environments.

Professor Del Tredici’s presentation at the Presidio Conference was entitled, “Saving Nature in a Humanized World.”  The presentation is available on YouTube.

We attended his presentation, which was warmly received by an audience of about 180 people.  We paraphrase some of his key points.

Update:  Professor Del Tredici has requested that the following statement be added to this post:  “Professor Del Tredici has graciously allowed us to paraphrase–for educational purposes only–some of his key points in his lecture. In no way should his permission to reprint the lecture on this website be considered an endorsement of the political or ecological agenda of “Death of a Million Trees”


Professor Del Tredici began his presentation by complimenting the Presidio for what it has accomplished in the past 20 years and congratulating the Presidio for “…what it has become.  But I’m going to do something very different today.  I hope you’re ready for this.”

Professor Del Tredici spoke about spontaneous urban nature, some of which we control but a lot we do not control.  What does spontaneous nature look like?  The reason why this is important is because it’s about the future.  What is the world going to look like 20 years from now?  The answer to that question is in urbanized nature.

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Detroit is a depressing place from a sociological standpoint.  It is so economically depressed that the land has lost its value.  Forty percent of the land is no longer occupied or managed by public or private entities. From the standpoint of a botanist, it is a fascinating place because we can see how nature develops without human interaction.  Detroit is a case study for urban ecology.

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Globalized Ecology

The vegetation of most cities is as cosmopolitan as its human population.  Asa Gray’s “Manual of Botany” reports that 10.7% of plant species in Northeastern United States were non-native in 1856.  By the 1990s, 25-35% of plant species were non-native.  This number is not going down.  It’s a strongly upward trend over the past 150 years.  We can create little islands of native plants by eradicating non-native species, but the reality is that our ecology is becoming as globalized as our economy.  These changes mirrored the changes in the ethnic and racial composition of American cities.  The same forces that produce socio-economic changes in cities are also changing the biological environment.

Urbanized Environment

A significant portion of land area in the Northeast is fully urbanized.  Urbanization in the West is just as rampant as the Northeast.  Looking at an aerial view of Los Angeles, you can see that it is completely developed.  You can talk about what used to grow there, but the concept that there is a vegetation that is native to these current conditions, Professor Del Tredici said, “Personally I find that an absurdity.  I hate to be so harsh, but nothing is native to LA as it now exists.”

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  • Cities have distinctive environmental characteristics, such as the urban heat island effect. Cities are significantly warmer than rural adjacent areas, which means they are important predictors of the impact of climate change because they have already warmed as much as other places are projected to in the future.
  • Urbanized areas can also be defined by the amount of impervious surface they contain. When 25% or more of the land is covered with an impervious surface such as roads, parking lots, houses etc., the environment is urbanized from the standpoint of the vegetation because impervious surface fragments the environment, compacts the soil, and interrupts the hydrology.   Using the definition of 30% impervious surface, urbanization describes not only our cities, but also many of our suburbs.
  • Glaciation is analogous to the urbanized environment because the heavy equipment that is used to clear the land leaves in its wake compacted glacial till. What you find after the glaciers recede is barren land; the vegetation has to come back from nothing—a condition known as primary succession.

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  • One-sixth of the city of Boston is built on land fill. What is the native vegetation of filled soil?  There is no going back when you’re talking about filled urban landscapes.  Not quite as much of San Francisco is built on landfill, but most of the eastern and northern edges of the city are on landfill.

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  • There is a huge difference between native soils and fill soils. Fill soils support the development of novel ecosystems. Native ecosystems cannot be created without native soils.  There are some native species that are adapted to urban conditions, such as roadside areas.  Urbanized vegetation is a cosmopolitan mix of native and non-native.  Urbanization favors species that grow well in soils that are relatively fertile, dry, sunny, and alkaline.

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  • Where it snows, the roads are repeatedly salted to prevent dangerous, icy conditions. This creates alkaline conditions along roadsides to which many plant species are not adapted.

Urban Ecology

Professor Del Tredici studies modern urban ecology which was born in post-war Germany, where urban environments were reduced to rubble and ecologists began to study what was growing in that rubble.  That was the birth of modern urban ecology.  It’s important to study, not for what it used to be, but for what it is now and what it can become in the future.  Nature reclaiming the urban environment on its own terms is an interesting process, an evolutionary process that we should pay attention to.  Post industrial succession—the process of rebuilding ecology in an intensively urban environment– should be studied with the same level of academic intensity as we studied the post-agricultural succession in the Northeast.

Novel Ecosystems

When native forests are converted to urban ecosystems and then abandoned—as seen in Detroit– they don’t go back to their original state, rather they become novel ecosystems.  There is no going back.  Once we achieve the level of compaction and impervious surface of an urbanized environment we have limited what the landscape can become in the future.  Some of these changes are permanent.  There are long term disturbances caused by chronic stress factors that permanently alter ecological conditions.  Professor Del Tredici said, “These conditions are not reversible.  Invasive species aren’t going anywhere.  If you remove invasive species you are gardening.  When you garden you are deciding who lives and who dies.  You are just playing god.  This gives you the illusion of control, but it is a never-ending effort to control a process that can’t be controlled.”

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In 1996 the Arnold Arboretum was given a 24 acre parcel of derelict land, called Bussey Brook Meadow. In 2011, Del Tredici succeeded in preserving it as a site for research on urban ecology by leaving it alone.  The land had a 300 year history of use and abuse, all left more or less alone.  Plant species—both native and non-native–have sorted themselves out and restored a functional wetland in the middle of the site.  It doesn’t matter that it isn’t a native landscape if it is providing the necessary ecological functions.

The Bottom Line

Ecology is not about stasis, it’s about flux.  Stasis is achieved by maintenance, but the natural state is flux.  Evolution is based on competition, which species is the best adapted to current conditions.  Sustainability is about reducing maintenance in order to promote ecology.  Landscape architects look at the Bussey Meadow site and ask, “When are you going to fix it?”  Professor Del Tredici’s answer is, “I’m not sure this site needs to be fixed.  It has value just the way it is.”

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We have quoted Professor Del Tredici’s work in previous articles and we consider it important everywhere, but we bring this presentation to your attention today primarily because of where it was delivered.  The Presidio Trust has engaged in some of the most aggressive “restorations” in the San Francisco Bay Area and some of the most successful: Inspiration Point, El Polin Spring, Thompson Reach, etc.  All fish in Mountain Lake were recently poisoned in order to “restore” the lake to exclusively native species.  Pacific chorus frogs were recently reintroduced.  The intention is to reintroduce the Western Pond Turtle to Mountain Lake, a species that is notoriously easily disturbed and being considered for endangered status.  It is also a species that requires hundreds of meters of unshaded nesting habitat in proximity to its water source.

Tennessee Hollow
Tennessee Hollow “Restoration” is 270 acres, 20% of the Presidio. Presidio Trust photo.

These projects have required the destruction of thousands of trees because the native vegetation is grassland and scrub.  However, the Presidio has also made a commitment to the preservation of its historic, non-native forest which was planted by the military over 100 years ago.  Major investments have been made in reforestation of the aging forest with similar tree species.

The San Francisco Presidio, painting by Richard Beechey, 1826
The San Francisco Presidio, painting by Richard Beechey, 1826

In other words, the Presidio Trust seems to have assigned itself a schizophrenic mission to simultaneously destroy an existing landscape in order to re-create it and preserve that same landscape: the re-creation of an idealized landscape vs. preservation of the novel ecosystem within the historic forest.   We suppose that is one definition of “balance.”  However, we would like to believe that the invitation to Professor Del Tredici to speak of the sustainability of urbanized novel ecosystems is an indication that the Presidio Trust will assign more value to what exists and less effort to attempts to re-create an historic landscape that may no longer be adapted to the real world.

What is the goal of ecological “restorations?”

In the not-so-distant past, the goal of ecological “restoration” was usually described as the re-creation of an historical landscape that was believed to have been undamaged by humans, presumed to be “in balance” and therefore sustainable after “restoration” without further human management.  In North America, the pre-European landscape is usually selected as the ideal landscape to be replicated, based on the assumption it had not been radically altered by Native Americans.  New knowledge has overturned this model:

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

Oddly, many invasion biologists accept these new understandings of ecological science without changing their deep commitment to eradicating all non-native plants and animals.  Daniel Simberloff published an article about the current status of the concept of “balance of nature” simultaneously with the publication of his defense of invasion biology.  He described the current thinking about this concept: “…a widespread rejection of the idea of balance of nature by academic ecologists, who focus rather on a dynamic, often chaotic nature buffeted by constant disturbances.”

Invasion biologists have therefore revised their goal for ecological “restorations” to accommodate their new understanding of the dynamic nature of ecosystems.

The revised goal of ecological “restorations”

If the return to an equilibrium state is no longer the goal of ecological “restorations,” what is the new goal?  This is how invasion biologists writing in defense of their discipline described their goal: “…we should seek to reestablish – or emulate, insofar as possible – the historical trajectory of ecosystems, before they were deflected by human activity, and to allow the restored system to continue responding to various environmental changes…” (1)

In this post we will deconstruct this new definition of the goal of ecological “restorations.”  Our first problem with this new definition is that we don’t know the “historical trajectory” of a landscape because it is fundamentally unknowable.  We would have to reconstruct all the events and changes in the environment in the Bay Area in the past 250 years in the imagined absence of any Europeans.  Even if we knew what would have happened without our presence, we cannot then ensure the continuation of that imagined environment because, the fact is, WE ARE HERE AND WE AREN’T GOING AWAY!

Because we cannot reconstruct an imagined environment that has not been “deflected by human activity,” restorationists—who are the practitioners of invasion biology–focus on the one element in the environment of which there is sufficient historical knowledge, i.e., plants.  Most local restoration projects eradicate all non-native plants and trees, usually using herbicides to accomplish that task.  They rarely plant anything after this eradication attempt because they don’t have the resources to do so.  Those few projects that re-plant after non-natives are eradicated usually irrigate the new landscape for several years.  Here is an incomplete list of everything these projects do not do to replicate an historical landscape:

  • Soils are not restored for many reasons:
    • We have no way of knowing the composition of soil 250 years ago.
    • Soils have been altered by the plants that have been growing in them and by the herbicides used to kill those plants.
    • Urban soils have high nitrogen levels resulting from exposure to fossil fuel exhaust.
  • The atmosphere is not restored:
    • There are much higher levels of ozone and carbon dioxide than there were 250 years ago.
  • The climate is not restored:
    • The temperature is higher than it was 250 years ago.
    • The timing of seasons has therefore changed.
    • Precipitation and fog have changed in known and unknown ways.
  • The disturbance events that sustained historical landscapes or set them on another evolutionary course are not restored:
    • We cannot set fire to urban landscapes annually without polluting our air and endangering our lives.
    • We cannot allow our creeks and rivers to overflow in urban areas without damaging our properties.
  • Most occupants of the historical landscape are not reintroduced:
    • The grazing animals that helped to sustain grassland are gone and cannot be returned to urban landscapes.
    • The top predators such as bears and wolves that kept grazing and other animals in balance with available resources cannot be returned without threatening our safety in an urban setting.
    • Many insects that lived in these historical landscapes are unknown to us and some are extinct.
The El Cerrito Plaza with the Albany Hill in the background, centuries ago.  Oil painting by Laura Cunningham, with permission
Bears roamed the grasslands in the Bay Area, preventing over-population of grazing animals. The El Cerrito Plaza with the Albany Hill in the background, centuries ago. Oil painting by Laura Cunningham, with permission

In other words, destroying plants will not “restore” an historical landscape.  Nor will it return that landscape to its “historical trajectory” even if that trajectory were known or knowable.  Plants live in complex communities in which they are interacting with everything in the environment.  Local “restoration” projects do not “restore” an historical landscape because they do not and cannot change anything other than the plants that occupy the space.  Because most environmental variables have not been altered by these projects, the landscape will quickly return to its unrestored state unless it is intensively gardened.  In that case, the landscape will be continuously “deflected by human activity,” which violates the original goal of invasion biologists.

Misanthropic premise of invasion biology

The revised goal of invasion biology is unattainable because the absence of humans is a prerequisite for its attainment.  We cannot know and we cannot replicate a theoretical historical trajectory for ecosystems in which humans were not present.  And when we modify ecosystems in an attempt to do so, human activities will determine their future trajectory. The premise of invasion biology is that success of ecological “restorations” depends upon the absence of humans. Therefore, invasion biology has no practical application in the real world.   


 

  1. Carolina Murcia, James Aronson, Gustavo Kattan, David Moreno-Mateos, Kingsley Dixon, Daniel Simberloff, “A critique of the ‘novel ecosystem’ concept,”Trends in Ecology and Evolution, October 2014, Vol. 29, No. 10

The American Prairie Reserve: Why is it controversial?

Our mission often obligates us to tell our readers about problems that we see with local “restoration”  projects in the San Francisco Bay Area, so when we see an opportunity to tell a positive story, we like to take it.  The New York Times recently published an article about the American Prairie Reserve that we think is probably a good example.  We say “probably” because this is a project in northern Montana that we won’t be able to visit and we don’t have first-hand access to the supporters or the critics of the project, so we have to admit that we could be wrong.

Missouri River from American Prairie Reserve.  Creative Commons.
Missouri River from American Prairie Reserve. Creative Commons.

The non-profit organization that operates the American Prairie Reserve is a group of conservationists who are funded by millionaire city-slickers who would like to see a hefty slice of the American prairie preserved, along with the wildlife that roamed free there when Lewis and Clark passed through in the early 1800s.  Their goal is to preserve 3 million acres of land.  So far, they have stitched together federal grazing leases on 215,000 acres of federal land and purchased 58,000 acres of former ranches.  They have removed 37 miles of fence and introduced 275 bison, a small start on what they hope will eventually be a huge herd.  They have planted native grasses.

American Bison.  NPS photo.
American Bison. NPS photo.

Their project is described in detail on their website which we encourage you to visit to see stunning photos of this beautiful land and its rare inhabitants.  We can’t share their photos with you because they are not in the public domain.

Here’s what appeals to us about this project:

  • Public access to the land is encouraged.  Hiking, hunting, and camping are allowed.
  • The project describes planting, not eradicating existing plants.  As we say repeatedly on Million Trees, we encourage native plant advocates to plant whatever they wish.  We ask only that they quit destroying everything else.
  • The project describes introducing new animals, rather than exterminating existing animals.
  • The project is being paid for by the people who support the project.  Taxpayers are not being asked to fund someone else’s hobby.

The caveats

Unfortunately, the ranchers in the neighborhood are worried that this project threatens their way of life.  Some of them have indicated that they will not sell their land to the project.  They are concerned that the loss of ranch properties will slowly diminish their community.  They worry that wealthy outsiders could price their families out of the market.  They don’t want their agricultural community transformed into a pricey tourist destination that would radically alter the character of their community.

The ranchers also consider themselves good stewards of the land“They rotate their herds to encourage a healthy mix of prairie grass and set aside ample room for sage grouse, plovers and heron.  They are trying to till less ground, which can destroy an underground ecosystem.  Some even allow small colonies of prairie dogs, which many farmers exterminate as pests.”  (1)

The conservationists who are supporting the project say they are trying their best to be good neighbors.  They buy land only when it goes on the market and then only at market-rate prices.  They installed electric fences so the bison do not disturb their neighbors.  They have even leased back some of the land they purchased to be grazed by ranchers.

The bottom line:  Is conflict inevitable?

The American Prairie Reserve looks as though it has everything going for it, including a remote location with a very low population of fewer than 5,000.  Yet, even when private money is used and every effort is made to accommodate those who live there, the project is controversial.  So, we should not be surprised that the “restoration” projects in the Bay Area are controversial:

  • Our projects ask the public to pay for projects that they often do not support.
  • Our projects often restrict the public’s access to the land that theoretically belongs to them.
  • Our projects eradicate plants and exterminate animals.
  • We live in a densely populated, urban environment where every acre of public space is precious.

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(1)    Jack Healy, “Vision of Prairie Paradise Troubles Some Montana Ranchers,” New York Times, October 26, 2013

“Ecological Restoration and Environmental Change”

Green Oaks, Knox College
Green Oaks, Knox College

Restoration and Environmental Change:  Renewing Damaged Ecosystems was written by Stuart Allison.  He is Professor of Biology and Director of Green Oaks Field Study Center at Knox College in Illinois.  His perspective on ecological restorations is unique because he is both a scientist and actively engaged in ecological restoration. 

There is a predictable tension between applied and theoretical science.  Ecology is particularly susceptible to this tension because its application is usually considered the immediate goal of the theoretical science that is intended to inform and guide it.  Therefore, we were very interested in Professor Allison’s viewpoint and we were intrigued by the suggestion of his title that his book would take into consideration the rapidly changing environment.

Although the restoration goal at Green Oaks is the re-creation of the tall grass prairie that is the historical landscape, Allison’s Ph.D. degree from UC Berkeley in Integrative Biology suggested that he is also familiar with our local ecology in the San Francisco Bay Area.  In fact, he mentions our controversy regarding the desire of native plant advocates to eradicate eucalyptus in California and he uses it to illustrate his opinion of novel ecosystems.

“When I was a graduate student at the University of California, Berkeley there was (and still is) a magnificent grove of blue gum (Eucalyptus globulus) outside of the Life Sciences Building.  It was rumored that they were some of the tallest blue gums in the world, growing so tall because they lacked any herbivores and diseases.  Eucalyptus trees grow beside roads all along California’s coastal highways and in the inland valleys of the coast ranges.  In fact, I cannot imagine California without eucalyptus trees.  But, of course, eucalyptus are not native to California–the first eucalyptus was introduced to California by Australian miners coming to the Gold Rush in the 1850s.  Today eucalyptus are so well established that many people think they are native to California, and even if they know they are not native, they don’t want to see them removed because to them, like me, eucalyptus are a central part of their experience of California.  Some people also fear that removal of eucalyptus will lead to erosion on steep hillsides and a decline in biodiversity.  In contrast, native plant enthusiasts in California would love to see eucalyptus permanently removed.  The dominance of eucalyptus in California is hardly unusual for a novel ecosystem, but it stands out because the trees came from Australia and because they are so striking in appearance and aroma that they can’t be missed.” (1)

Professor Allison then acknowledges that some scientists are now interested in and respectful of novel ecosystems such as the eucalyptus forest.  However, he is worried “that novel ecosystems will lead to a homogenized world in which the same species…are found everywhere.”   That debate is not the central theme in his book.  His primary objective is to take the pulse of his colleagues in ecological restoration and report the changes in their objectives in the past 20 years, given the rapid changes that have occurred in the environment.

What is the goal of ecological restoration?

The Society for Ecological Restoration (SER) is the professional organization recognized by most restorationists.  Its Policy Working Group claims that “an ecosystem is fully restored and the project has been completed when the restoration ‘contains sufficient biotic and abiotic resources to continue its development without further assistance or subsidy.’”

Annual Prairie Burn, Green Oaks, Knox College
Annual Prairie Burn, Green Oaks, Knox College

Professor Allison tells us that the restoration in which he has been engaged for over 20 years will never achieve that standard:  “The tall grass prairie and savanna restorations I work with are all based on a return to historical pre-Euro-American disturbance, but all require perpetual management and human intervention to maintain them on the desired ecological trajectory.  Without regularly applied fire, those ecosystems would soon become dominated by many woody species and grow into a woodland lacking prairie or savannah characteristics.”  Professor Allison describes the annual “Prairie Burn” at Green Oaks which is considered an important social event by students at Knox College.

This is one of many ironies about ecological restorations.  Many projects are attempting to re-create an historical landscape at a specific period of time, which was not the result of natural succession.  In the case of grassland prairie, it was largely the result of periodic fires set by Native Americans.  Left to its natural devices, grassland would soon be “invaded” by shrubs and over time it would become a forest if soil and climate conditions were suitable.  In that sense, it is an artificial landscape, as unnatural as any manmade garden.  That the humans who created that historical landscape were indigenous, as opposed to European settlers, seems to us a meaningless, legalistic quibble.

The “field of dreams” theory

Most restoration projects focus almost entirely on plants.  Little explicit attention is paid to the animals that are the desirable inhabitants of the restoration.  Restorationists believe that if the habitat is made available, the animals will quickly follow.  This is the “field of dreams” theory, i.e., if we build it, the animals will come.   This is magical thinking.

Restoration projects rarely monitor the results of their projects sufficiently to test this theory.  In the San Francisco Bay Area, native plant advocates claim there are more birds and animals occupying restoration sites, but these are anecdotal observations that cannot be verified.  Nor do they seem credible to skeptics of the projects, who often think the habitat that has been eradicated actually supported more wildlife. 

Evolving goals of restoration projects

Here in the San Francisco Bay Area we have observed the changing objectives of ecological restorations.  Over fifteen years ago, local projects were touted as “sustainable.”  The public was told that once restored to historical equilibrium conditions, the projects would be capable of sustaining themselves without further resources. 

Comparson of pesticides used by San Francisco's "Natural Areas Program" compared to landscaped areas of San Francisco's parks
Comparson of pesticides used by San Francisco’s “Natural Areas Program” compared to landscaped areas of San Francisco’s parks. Photo courtesy of SF Forest Alliance.

We no longer hear that claim.  Now we are told that our “natural areas” must be managed in perpetuity.  More herbicides are used in San Francisco’s “natural areas” than landscaped portions of the parks, with the exception of a professional tournament golf course.  And if we want the animals that historically occupied those areas, they must be reintroduced, using labor-intensive methods.

Professor Allison observes the same “mission creep” amongst his colleagues.  The goal of replicating an historical landscape is no longer the dominant theme of ecological restorations.  Now the goal is more commonly defined in terms of increasing “biodiversity” and improving “ecological functions.”

New buzz words

If the new goal of ecological restorations is greater biodiversity and improved ecological functions, it seems reasonable to ask what these terms mean.  Unfortunately, we were unable to find the answer to that question in Professor Allison’s book.  Those terms are used as though their meanings are intuitively obvious.  They are not.  These terms are jargon that has little intrinsic meaning and they probably mean different things to different people.

When scientific studies quantify biodiversity, they count species of both native and non-native plants and animals.  Since there are now far more species of non-native plants and animals and far fewer extinctions of native plants and animals, biodiversity has increased virtually everywhere in the world.  So, as far as science is concerned, how could a restoration project that eradicates all non-native species result in greater biodiversity?

Obviously native plant advocates are defining the word “biodiversity” differently than traditional science.  Native plant advocates seem to define biodiversity as exclusively native.  Furthermore, the nativist ideology believes that the mere existence of non-native plants and animals will inevitably result in the extinction of native plants and animals.  There is little scientific evidence to support this assumption.  Few extinctions have been attributed to the existence of non-native plants and no extinctions blamed on non-native plants have occurred in the continental United States.

The term “ecological functions” is even more mysterious as it relates to ecological restorations.  It could mean almost anything:  production of biomass, soil composition, photosynthesis, carbon sequestration and storage, nutrient cycling, fire regime, hydrologic cycle, etc. 

Professor Allison does not provide us with his definition of this term, so we will make an assumption based on our knowledge of ecological scientific literature.  We told our readers about a study in Hawaii which compared native and non-native forests with respect to the ecological functions they are performing.  In that study, three such functions were measured and reported:  carbon sequestration, production of biomass, and nutrient cycling.  The study concluded that non-native forests were performing these ecological functions as well as native forests. 

We can also compare treeless grassland prairie with a native or non-native forest with respect to those ecological functions.  Forests—whether native or non-native– will fulfill these and other functions at least as well as the grassland prairie.  If we add the factor that the grassland prairie must be burned annually to maintain it, clearly the grassland prairie is an ecological deficit because it releases pollutants and greenhouse gases into the atmosphere when it is burned.

The moving target

The goals of ecological restoration are a moving target.  The original goals of re-creating an historical landscape that would be sustainable without continual maintenance are now widely acknowledged to be unrealistic. 

The new goals are equally elusive.  The new goals are described in obscure ways that will be impossible to measure or evaluate.  That suits the purposes of native plant advocates perfectly.  They can continue to do whatever they want and the public can’t hold them accountable because the public is not provided with a practical method of measuring success or failure.  

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(1)    Stuart K. Allison, Ecological Restoration and Environmental Change:  Renewing Damaged Ecosystems, Routledge, UK, USA, Canada, 2012