Talking back to nativism

Dana Millbank is a political columnist for the Washington Post. He broke out of his political mold on April 7, 2023 to write an article about gardening published by the Post, which repeats every myth of the nativist ideology. 

A team of dismayed critics of invasion biology has responded to excerpts of Millbank’s column:

  • Marlene A. Condon is a garden writer based in Virginia and the author of The Nature Friendly Garden. She has a degree in physics. Her entire critique of Millbank’s column is available on her website.  Her comments address the reader.
  • Carol Reese is a retired Extension Horticulture Specialist who conducted her 27 year career from the University of Tennessee’s West Tennessee AgResearch and Education Center in Jackson, where a large and diverse display garden gave her the opportunity to observe biodiversity in action on an enormous range of plant species from other parts of the world. She describes herself as a farm raised country girl tomboy who has looked at the natural world in hundreds of settings and landscapes, natural and manmade, and read countless books and articles. She has written for several magazines, newspapers, articles for Garden Rant as well as university publications.  Her speaking engagements around the country have allowed her to engage with many other green industry professionals. Dana Millbank’s column prompted her to email him directly with her concerns, directly addressing some of his assertions. I publish some excerpts here from her emails sent directly to Millbank.
  • Conservation Sense and Nonsense is the webmaster of this website.  I have studied invasion biology and the native plant movement it spawned for over 25 years. I’ve watched forests of healthy, non-native trees in California be destroyed and replaced by weedy grassland.  I have used what I have learned to advocate for a less destructive approach to restoration, a word I am reluctant to use to describe projects that use herbicides to eradicate harmless plants and trees. My comments are addressed to the reader.

What follows are excerpts from Dana Millbank’s column with responses from Marlene Condon, Carol Reese, and Conservation Sense and Nonsense, just three of many skeptics of invasion biology.  To summarize the point of our criticism:

  • Insects are not dependent on native plants.  They are just as likely to use related non-native plants in the same genus or even plant family with similar chemical properties and nutritional value. 
  • While some non-native plants have potential to be harmful, many are beneficial. There are pros and cons to both native and non-native plants and that judgment varies from one animal species to another, including humans. For example, we don’t like mosquitoes, but they are important food for bats and birds.  
  • All plants, whether native or non-native convert carbon dioxide to oxygen and store carbon. Destroying them contributes to greenhouse gases causing climate change.
  • When the climate changes, vegetation must also change.  Many non-native plants are better adapted to current climate and environmental conditions in disturbed ecosystems.

Conservation Sense and Nonsense

“I’m no genius about genuses, but your garden is killing the Earth”
By Dana Millbank
Washington Post, April 7, 2023

Millbank:  I did almost everything wrong.

ReeseI’m so sorry you thought this!

Millbank:  For 20 years, I found the latest, greatest horticultural marvels at garden centers and planted them in my yard: sunny knock-out roses, encore azaleas, merlot redbud, summer snowflake viburnum, genie magnolia, firepower nandina.

In between them flowed my lush, deep-green lawn. I hauled sod directly from the farm and rolled it out in neat rows. I core-aerated, I conditioned, I thatched, I overseeded, I fertilized. I weeded by hand, protecting each prized blade of tall fescue from crabgrass and clover.

In this season, a symphony of color performs in my yard. The fading daffodils, cherry blossoms, saucer magnolias, hyacinths and camellias meet the arriving tulips, lilacs, creeping phlox and azaleas, with the promise of rhododendrons, peonies, hydrangeas, day lilies and roses to debut in the coming weeks.

But this year, the bloom is off the rose. And the hydrangea. And the rhododendron. And all the rest. It turns out I’ve been filling my yard with a mix of ecological junk food and horticultural terrorists.

Condon:  When Mr. Millbank posits that he’s “been filling his yard with a mix of ecological junk food and horticultural terrorists,” he’s channeling the kind of words Bringing Nature Home author Doug Tallamy loves to employ:  Biased expressions that implant negative images in the reader’s mind so he will become yet another minion of this scientist.  Nowadays you can’t read a garden or environmental column without being accosted with the same words or variations thereof, as if everyone has become a mouthpiece for Doug Tallamy, which I’ve never seen done more obviously than in this column by Dana Millbank. 

Conservation Sense and Nonsense:  Millbank’s lengthy list of “bad” plants in his garden paints with too broad a brush.  For example, instead of identifying a particular species of hydrangea and rhododendron, Millbank condemns an entire genus.  Both hydrangea and rhododendron genera have several native species within the genus.  Most (all?) species of phlox are also native to North America. 

Millbank:  When it comes to the world’s biodiversity crisis — as many as 1 million plant and animal species face near-term extinction because of habitat loss ― I am part of the problem. I’m sorry to say that if you have a typical urban or suburban landscape, your lawn and garden are also dooming the Earth.

Reese:  YIKES! This is pretty extreme, and dare I say inaccurate? No, home gardeners are part of the solution, no matter the plants in their garden. Doom will come from lack of diverse green space. Doom will come from climate warming as a result, as well as from pollution, tillage, factory farming and development.

Millbank:  I came to understand the magnitude of my offenses after enlisting in nature boot camp this spring. I’m in “basic training” with the state-sponsored Virginia Master Naturalist program. While others sleep in on rainy weekend mornings, my unit, the Arlington Regional Master Naturalists, has us plebes out in the wetlands distinguishing a yellow-bellied sap sucker from a pileated woodpecker.

I’m no genius with genuses, but I know a quercus from a kalmia, and because of my gardening experience, I began the program with confidence. Instead, I’ve discovered that all the backbreaking work I’ve done in my yard over the years has produced virtually nothing of ecological value — and some things that do actual harm.

A few of the shrubs I planted were invasive and known to escape into the wild. They crowd out native plants and threaten the entire ecosystem. Our local insects, which evolved to eat native plants, starve because they can’t eat the invasive plants or don’t recognize the invaders as food.

Anise swallowtail on non-native fennel. Courtesy “Papilio zelicaon, the anise swallowtail, typically has one to two generations in the mountains and foothills of California where it feeds on native apiaceous hosts. However, along the coast, in the San Francisco Bay Area and the urbanized south coastal plains and in the Central Valley, P. zelicaon feeds on introduced sweet fennel, Foeniculum vulgare, and produces four to six or more generations each year… the use of exotics has greatly extended the range of P. zelicaon in lowland California.” SD Graves and A Shapiro, “Exotics as host plants of the California butterfly fauna,” Biological Conservation, 2003

Reese:  It sounds so logical, but is sooo inaccurate. Ask any entomologist that has spent their careers “fighting pests” on valued crop or ornamental plants. Remember Pangea [when all continents were fused into one]? More recently, have you thought about the exchange of plants and animals across Berengia when we were still connected to Asia? We can trace those relationships/kinships of our plants to Asian/Eurasian plants now through DNA. They eventually differentiated into species (a continuum of change caused by climate and geologic pressures until we [Man] declare it as a different species, though biologically it is still basically the same nutritional makeup)

Condon also dissects Millbank’s statement: 

  • “They crowd out native plants and threaten the entire ecosystem.”  Read virtually any description of where you find so-called invasive plant species and you will find the word “disturbed.”  This tells you the soil profile has been negatively impacted by people, animals, or weather, and usually means the topsoil is gone.  Only very tough plants—known as colonizers—can grow in disturbed areas because the soil is nutrient-poor and is typically compacted.  Consequently, these areas may fill with a mix of native and nonnative plants, or mainly one or the other—but every single plant is a colonizer that is working to rehabilitate the land for the benefit of the native plants that require topsoil in which to grow.  “Invasiveness” is nothing more than a derogatory word used by people with contempt for alien-plant colonization.  Conclusions:  Alien plants can’t “crowd out” native plants because once the soil is disturbed and thus degraded, most of our native plants can’t grow there and thus are not there to be crowded out.  As for “threatening the entire ecosystem,” to the contrary, alien colonizers are helping to restore it.
  • “Our local insects, which evolved to eat native plants, starve because they can’t eat the invasive plants or don’t recognize the invaders as food.”  This oft-repeated distorted premise comes straight out of Bringing Nature Home, in which Doug Tallamy deceptively writes about “an excellent demonstration of how restricted a specialist’s [an insect with particular food preference] diet is.” Tallamy tells the story of Eastern Tent caterpillars on a cherry tee denuded of its own leaves but hosting a Japanese Honeysuckle vine.  He writes that the caterpillars didn’t recognize the honeysuckle as food (sound familiar?)  But, of course, they didn’t because this species of insect can only eat plants in the Rose Family, which does not include honeysuckle.  What Doug Tallamy doesn’t tell the reader is that the tent caterpillars could certainly have eaten the so-called invasive Multiflora Rose, which I’ve documented in the photo below.  Conclusion:  Native insects did not evolve to eat only local (native) plants, but rather can typically feed upon dozens, if not hundreds or thousands, of plants related to each other by family classification, even though they grow in other countries.
Tent caterpillar on multiflora rose.  Photo by Marlene Condon.

Millbank:  This in turn threatens our birds, amphibians, reptiles, rodents and others all the way up the food chain. Incredibly, nurseries still sell these nasties — without so much as a warning label.

Reese:  As I read, I also watch the many birds on my lawn, the fence lizards on my decks, the insects humming among the flowers in my diverse collection of native cultivars and introduced plants. 

Hummingbird in eucalyptus flower. Eucalyptus blooms from November to May. It is one of the few sources of nectar and pollen for birds and bees during the winter months when little else is blooming. Courtesy Melanie Hoffman
Eucalyptus leaf litter makes excellent camouflage for this garter snake. Courtesy Urban Wildness

Millbank:  Most of my other plants, including my beloved lawn, are ecological junk food.

Reese:  Now, now! Many (most) natives do not supply useful forage either. All plants supply some benefit. They provide shelter, create, improve and anchor soil, cleanse air and water, make oxygen and cool the planet. The plant must be judged on benefits versus detriments in each situation. If a nonnative plant is the only thing that will flourish in bombed out rubble, or contaminated soil, if it is providing many benefits, shall we rip it out because caterpillars won’t eat it? If we let it get established, will it ready the site for other species with more benefits to become established? Shall we get out of the way and let nature do what she does, which is heal herself?

Millbank:  The trees, shrubs and perennials are mostly “naturalized” plants from Asia or Europe or “cultivars,” human-made varieties of native plants bred to be extra showy or disease resistant but lacking genetic diversity or value to animals. I, like other gardeners I know, planted them after mistaking them for their native cousins. They’re not doing harm, but neither are they doing anything to arrest the spiral toward mass extinction.

Reese:  Please know that the most influential native plant botanical garden in the country (Mt. Cuba Center)  has trialed the cultivars of native plants for their ecological benefits and found as should be expected, that each cultivar must be judged on its own merits. Some are better than the straight native as in the coneflowers where ‘Fragrant Angel’ scored tops for pollinators and many others were very close to being as good as straight species. These cultivars were even better than the other species of Echinacea tested. BTW, I grow E. purpurea, pallida, paradoxa, tennesseensis and laevigata as well as many cultivars. Remember that cultivars should also be judged on not just nutritional value, but other factors that increase benefits, such as length of bloom period, numbers of blooms, drought resistance, heat tolerance, hardiness, ease of production (cost) and durability. Please ask to speak to Sam Hoadley there as he leads the research on beneficial cultivars and has completed and undertaken several studies of different native species. Great guy and great speaker. 

Please be aware that many cultivars originated as naturally occurring deviations in seedling populations, and as we know this actually diversifies the genetic pool, allowing Mother Nature to select the better form. We sometimes agree with her, and other times we may move along that diversifying form by crossing it with others that are demonstrating genetic variance. Logically, this actually furthers the cause of a broader genetic pool that can help in today’s crisis in showing which can cope and flourish.

Millbank:  To get a sense of my missteps, I asked Matt Bright, who runs the nonprofit Earth Sangha, a native-plant nursery in Fairfax County (and a lecturer on botany for my nature boot camp) to walk through my yard with me.

He took aim at my day lilies: “I would remove them all. Those have also become badly invasive.”

He spied my creeping jenny on a slope: “Another nasty invasive.”

He condemned to death my rose of Sharon shrubs (natural areas “have really been torn up by these guys”) and my innocuously named summer snowflake viburnum.

Worst was my row of nandinas — “heavenly bamboo” — along the foundation. “You definitely want to remove it,” he advised. Its cyanide-laced berries poison birds.

Condon:  This tactic is typical of the followers of Tallamy who want folks to perceive supposedly invasive plants as “bad” even though no evidence exists to support their accusations, especially in this instance.  Mr. Millbank and Mr. Bright, who obviously supplied this information, have misspoken here.  A study out of the University of North Carolina, Chapel Hill, published in 2022, explains that Cedar Waxwings are the only birds that might be poisoned, and that’s only going to happen if someone grows so many nandinas that these birds consume large numbers of fruits in a single feeding bout.  If you grow just one or even a few plants, you are not going to poison waxwings.

Conservation Sense and Nonsense:  Here in California, most berry-producing, non-native plants are considered “invasive” based on the assumption that birds eat the berries and spread the plants.  Nandina was briefly on the list of invasive plants in California until knowledgeable people informed the California Invasive Plant Council that birds don’t eat the toxic berries.  Nandina was removed from the invasive plant inventory long ago.

Bumblebee on Cotoneaster, Albany, CA. Cotoneaster is one of many berry-producing non-native plants on the list of invasive plants in California. Himalayan blackberries are another target for eradication in California. They are frequently sprayed with herbicide in public parks where children and other park visitors eat the blackberries.

I also have personal experience with nandina and cedar waxwings.  Flocks of waxwings visited my holly trees in San Francisco every year.  They did not touch my three nandina plants.

California buckeye (Aesculus californica) is an example of a native tree that is toxic.  Its flowers are toxic to honeybees and its big brown seeds for which it is named were used by Indigenous people to stun fish to make them easier to catch.  The bark, leaves, and fruits contain neurotoxic glycoside aesculin.  Every negative characteristic attributed to some non-native plant species is equally true of some native plant species.  No one mentions buckeye’s toxic characteristics because it’s a beautiful native tree.  Photo Sacramento Tree Foundation

Condon:   I’ve had a Rose of Sharon (Hibiscus syriacus) growing in my yard since I moved to my home in Virginia almost 40 years ago. In all this time, only one seedling from the plant I brought here has ever “volunteered” to become a second yard denizen.  During the past 37 years, pollinators have fed at the original plant and then also at its offspring. What I’ve found by experience in my yard is that few plants can successfully move into a space that’s already filled with other plants. (Proving what physics tells us–that no two physical objects can occupy the same space).  I’ve brought home numerous so-called invasive plants, only to have them disappear or simply stay put where I planted them. That’s because hundreds, if not thousands, of plants fill my yard. 

Conservation Sense and Nonsense:  Virginia is one of only four states in which rose of Sharon is considered invasive.  Condon’s experience with rose of Sharon in Virginia suggests that lists of “invasive plants” are either inaccurate or are serving another purpose (perhaps both).  The longer the list of “invasive plants” the more work is created for the “restoration” (AKA eradication) industry.

Rose of Sharon is not considered invasive in California. This is a reminder that the behavior of plants varies because of the wide range of climate and environmental conditions.  Nearly one third of the plants on California’s list of invasive plants are not considered invasive in California.  They are on the list because they are considered invasive in Hawaii, a state with a warmer, wetter climate than California.  In naming rose of Sharon as a dangerous invasive, a media resource with a national readership has made a generalization that red-lines more plants than necessary.  They become targets for eradication with herbicide and they deprive us of the biodiversity that is particularly important in a changing climate in which biodiversity ensures resiliency.

Millbank:  Bright did praise two “good” species I have that contribute to biodiversity: a sycamore and a catalpa as well as a “great” American elm and a “phenomenal” dogwood. (I couldn’t take much pride in them, though, because all four were here long before I arrived.) And Bright assured me I wasn’t a particularly egregious offender; my one-sixth acre lot in town is typical of the urban/suburban landscape.

●  ●  ●

Lawns, and those useless, ubiquitous cultivars of trees, shrubs and perennials sold by the major garden centers, are squelching the genetic variety nature needs to adapt to climate change.

Reese:  It’s actually the opposite. We need more plants in the mix. We need “the tumult of nature” to decide. We aren’t the jury, and we continue to interfere with our well-intended assumptions that we know best.

Lawns are full of wildlife when management is minimal. Mow. That’s all. Mow judiciously when “lawn weeds” are blooming. Watch birds feed on the many insects in the lawn including lepidopteran larvae. Realize that many moths pupate underground. Think of your lawn as haven for them and for the grubs birds relish as millions of acres across our country are being tilled for factory farms. Remember that the best habitat is mixed. Open areas bordered by wooded areas and most species love the borders. Our suburban landscapes are ideal if we just stop killing things.

This is a lawn that serves pollinators. Homestead Stencil Company

Millbank:  The resulting loss of native plants in our fragmented urban and suburban landscapes deprives both plants and wildlife of the contiguous habitats they need to breed and, over time, to migrate in response to climate change.

The deck is stacked against nature in this fight.

●  ●  ●

If possible, you should remove the nastiest of the invasive plants if you have them: burning bush, Japanese barberry, Asian bush honeysuckle, English ivy, callery (Bradford) pear and a few others.

But leave the rest of your plants alone, for now. Tallamy ultimately wants to cut lawn acreage in half, but “there is room for compromise,” he said. Think of your noninvasive plants and cultivars as “decorations.”

Janet Davis, who runs Hill House Farm & Nursery in Castleton, Va., has a similar message for the purists who make you feel bad about your blue hydrangea. “Don’t give me crap about something that’s not native but not invasive,” she said. “I’m never going to tell you you can’t have your grandmother’s peony.”

Thus absolved, I shed my guilt about my yard full of ecological empty calories. I kept my hydrangeas, azaleas and roses but pulled out the truly bad stuff. I dug up the nandinas and replaced them with native winterberry holly, red chokeberry and maple-leaf viburnum. I removed the rose of Sharon and substituted American hazelnut and witch hazel. I uprooted the invasive viburnum and planted a native arrowwood viburnum in its place.

I also took a small step in the painful task of killing my beloved lawn. I used landscape fabric to smother about 400 square feet of turf. In its place, I planted a smattering of canopy trees (two white and two northern red oaks), understory trees (ironwood, eastern redbud), shrubs (wild hydrangea, black haw viburnum) and various perennials and grasses (Virginia wild rye, blue-stemmed goldenrod, American alumroot, woodrush, spreading sedge).

My 38 plants cost $439 at Earth Sangha. But these natives, adapted to our soil and conditions, don’t require fertilizer, soil amendments or, eventually, much watering. Over time, I’ll save money on mulch and mowing.

Reese:  This one is so oft repeated and so very wrong. It depends on the plant, and it depends on the site. Plants in the wild require no input to succeed whether native or not because we have not messed up the soil and we have let the natural cycles of plant debris/decay improve the soil as it was meant to, creating a live, moist, interaction of microorganisms that work symbiotically to support the plant, which, btw has also been selected by nature for that site. It has absolutely nothing to do with origins. In fact, why would nonnative plants become “invasive” if they did not adapt as well or better than the native plants? I want to snort with laughter!

Millbank:  Right now, my seedlings look pretty sad. Where once there were healthy lawn and vibrant shrubs, there is now mud and scrawny sprigs poking from the ground every few feet. I put up chicken wire to keep the kids (and me) from trampling them. The carcasses of my invasive plants lie in a heap on the gravel.

Condon:  This statement supports my contention that ridding your yard (and, in the case of government, natural areas and parks) of “invasive” plants destroys habitat, leaving our wildlife high and dry.  Follow the advice of Doug Tallamy, via Dana Millbank (and many others) and you make the environment far less hospitable to our wildlife by removing plants that supplied habitat NOW when our critters need it to survive.

Conservation Sense and Nonsense:  This description of Millbank’s ravaged garden is consistent with my 25 years of observing native plant “restorations” on public land.  They all begin with destruction, usually accomplished with herbicides.  The first stage of these projects is often described as “scorched earth.”  Years later, there is rarely habitat comparable to what was destroyed.  Colored flags usually outnumber plants. 

This is what a native plant garden on Sunset Blvd in San Francisco looked like after two years of effort: more colored flags than plants. The sign claims it is “pollinator habitat.” Since when do pollinators eat flags?

Millbank:  But in a couple of seasons, if all goes well, my yard will be full of pollinators, birds and other visitors in need of an urban oasis. Years from now, those tender oak seedlings, now 6-inch twigs, will stretch as high as 100 feet, feeding and sheltering generations of wild animals struggling to survive climate change and habitat loss.

Conservation Sense and Nonsense:  Destroying harmless vegetation contributes to climate change by releasing carbon stored in the living vegetation and reducing the capacity to sequester more carbon.  Above-ground carbon storage is proportional to the biomass of the living vegetation.  Destroying large, mature plants and trees releases more greenhouse gases in the atmosphere than the young plants and trees can sequester.  Meanwhile, the climate continues to change and the native plants that Millbank prefers are less and less likely to be adapted to conditions.  Native plant ideology is a form of climate-change denial. 

A small forest of non-native trees was destroyed in a San Francisco park to create a native plant garden. Nine months later, this is what the project looked like: a tree graveyard.

Millbank:  I won’t be alive to see it. Yet even now, my infant oaks give me something the most stunning cherry blossom never could: a sense of hope.

Conservation Sense and Nonsense:  I feel bad for Dana Millbank.  He has been successfully guilt-tripped into believing he has damaged the environment.  He hasn’t, but destroying his harmless garden WILL damage the environment. 

We hope he will find his way back to a less gloomy outlook on nature, which will outlast us all in the end.  Altered perhaps, but always knowing best what it takes to survive.  The way back from the cliff he is standing on is through a study of evolutionary change through deep time to appreciate the dynamic resilience of nature, which may or may not include humans in the distant future.  Our message is “Embrace the change because change will enable survival.”

Suggested reading for those standing on the steep cliff created by nativism in the natural world:

Sunset Blvd: Biting off more than you can chew

Sunset Blvd is a major traffic artery that runs through the middle of the Sunset District, on the west side of San Francisco.  It is one of only three traffic arteries in the Sunset.  The Great Highway on the western edge of the Sunset, separates ocean beach from the dense residential neighborhood called the Sunset District.  The Great Highway is closed to traffic from Fridays at noon to Monday at 6 am for recreational purposes.   19th Avenue, on the eastern edge of the Sunset is State Highway 1, a major entrance into San Francisco from the south and north that is heavily congested around the clock. 

In other words, Sunset Blvd is vitally important to traffic traveling into and through San Francisco.  Yet, San Francisco’s “biodiversity coordinator” calls Sunset Blvd a wildlife corridor from Lake Merced to Golden Gate Park and he was instrumental in creating the Sunset Blvd Biodiversity Master Plan that is trying to transform Sunset Blvd into a 2-1/2 mile long densely planted garden.  The gardens are being funded by grants and non-profit organizations and planted by volunteers with no commitments for long-term maintenance.  The gardens are being watered by hand by the volunteers because the sprinkler system is no longer functional.  Faucets (quick couplers) were installed in each block as a substitute for the sprinkler system. 

Implementation of the Sunset Blvd Biodiversity Master Plan has been in progress for over 4 years.  This article is a progress report that is also a lack-of-progress report on a plan that seems to us misguided in some ways and too ambitious.  Sunset Blvd looks like a mess now, but it will be substantially worse when the short-term grants and volunteer commitments expire because the city does not have the resources to maintain it for the long-term.

Natural History of the Sunset District

This birds-eye view of San Francisco in 1868 (see below) shows why it’s challenging to garden in the Sunset District.  Most of the District was barren sand dunes.  The district is foggy during the summer and windy throughout the year.  There were few plants on the sand dunes and no trees.  Trees that are native to San Francisco do not tolerate salty ocean winds and sandy soil that doesn’t retain the moisture of our limited seasonal rain. 

Sunset Blvd was built in 1931, at a time when the Sunset District was barren sand.  It was planted with Monterey pines and cypress that are native less than 150 miles south of San Francisco, in a similar climate.  The trees were planted to provide a wind break for the residential neighborhood east of Sunset Blvd as well as to beautify a neighborhood that many consider bleak during the foggy days of summer. 

This (see below) is what Sunset Blvd looked like in the 1990s when I lived in the Sunset District:  A tall windbreak of Monterey cypress and pines with tall non-native shrubs below the canopy and mowed lawn on both sides of the windbreak, the sidewalk medians, and the center median.  It was a landscape that is easy to maintain because it can be mechanically mowed and irrigated with automatic sprinklers.  It was a simple, neat, and functional landscape.

The Sunset Blvd Biodiversity Master Plan

The windbreak on Sunset Blvd is dying of old age, which should be expected, given its age.  Reforestation should have begun decades ago in anticipation of the death of Monterey pines and cypress.  By 2019, many hazardous trees had been removed and 250 new trees were planted, with another 100 trees planned.  This year, intense winter storms have toppled many more trees on Sunset Blvd (and elsewhere), suggesting that all hazardous trees have not been removed. Public safety should be the top priority for any renovation project.  That doesn’t seem to be the case in this project.

Climate Action Network (CAN) obtained Cal Fire grants to plant trees and shrubs from Lawton to Pacheco.  They have planted a mix of both natives and non-natives and most are doing well after unusually heavy winter rains, 10 inches more than San Francisco’s average annual rain total of less than 23 inches. 

Lawton block of Sunset Blvd., January 2023

The master plan makes a commitment to create nine small native plant gardens done by several different organizations, including student organizations.  Department of Public Works—which is responsible for Sunset Blvd–has also given the entire block from Santiago to Taraval to the California Native Plant Society (CNPS) to garden with exclusively native plants. The Memorandum of Understanding (MOU) with CNPS also gave them the block from Kirkham to Lawton to plant a wildflower meadow.  The meadow CNPS planted there failed and that part of their plan has been abandoned.  The MOU with CNPS obligates them to provide the plants, irrigate, and maintain the garden for three years.  Many dead tree saplings in that block suggest watering may be haphazard. CNPS has made the most effort at the corner of Taraval and Sunset Blvd.  These three photos (below) show what this small native plant garden looks like at different times of the year. 

Taraval and Sunset Blvd, spring 2022. CNPS photo
Taraval and Sunset Blvd, October 2022
Taraval and Sunset Blvd, January 2023

The center median of Sunset Blvd that was mowed and irrigated grass in the past was planted with a mix of native and non-native drought tolerant plants several years ago.  After several years of intense drought and no available irrigation, only the succulents survived, leaving bare ground populated by weeds that can’t be mowed because of the succulents.  The weeds are sprayed with herbicide by Department of Public Works.  In 2021, the center median was sprayed 38 times with 238 gallons of herbicide. Thankfully, the wide medians between the boulevard and side streets are not being sprayed with herbicide. In 2021 and 2022, over 20% of all herbicide spraying by DPW was done on the center median of Sunset Blvd. 

The Public Utilities Commission has created 151 rain gardens in San Francisco and about 30 of them are on Sunset Blvd.  PUC is using both native and non-native plants, but they are under intense pressure from native plant advocates to plant exclusively natives. The rain gardens aren’t irrigated, so they look pretty shabby during dry summer months. Although they reduce run off into the sewer system, some members of the public are likely to judge them by what they look like. PUC is trying to recruit neighbors to take care of them.  The Sunset Blvd Biodiversity Master Plan leans heavily on the public to take care of Sunset Blvd.

Rain garden on Sunset Blvd, August 2022

What do Sunset residents want?

Is the Department of Public Works (DPW) giving residents what they want on Sunset Blvd?  The do-it-yourself playgrounds and seating areas created by neighbors may be a better indication of the preferences of Sunset residents.  This DIY playground (see below) has provided seating, a play structure, a basketball hoop, and a horseshoe throw.  On a sunny Sunday morning in January 2023, the adults were supervising their children in their homemade playground.  A mowed lawn would provide space for such recreational activities.

Homemade playground on Sunset Blvd, January 2023

There are also DIY gardens with seating that have been created by neighbors.  In this case (see below), non-native succulents have been planted in some of the many logs of dead trees on Sunset Blvd.

Homemade garden on Sunset Blvd., January 2023

San Francisco city officials had something different in mind.  The design goals of the Sunset Blvd Biodiversity Master Plan were:

Create Meaningful Public Spaces:
– Create areas of passive and active recreation that build on neighborhood cultural resources
– Design an immersive trail experience that connects to citywide trail network
– Engage the community through outreach initiatives for planting, maintenance, and education
Cultivate a Biodiverse Landscape:
– Support San Francisco Biodiversity Resolution
– Plant native species that provide critical wildlife habitat with a focus on insects, pollinators, and birds
– Develop educational opportunities to learn about local biodiversity and wildlife
Provide Ecosystem Services:
– Manage stormwater with green infrastructure to support PUC initiatives
– Minimize water use with drought tolerant plants
– Sequester carbon by increasing plant diversity [Carbon storage is not related to plant diversity.]

This is what city officials have actually delivered on Sunset Blvd:

  • A complex landscape that must be watered by hand by volunteers. 
  • A landscape that can’t be mowed because it has been intensively planted with plants.
  • A landscape that is dominated by weeds, except in the center median, which is sprayed with herbicide.
  • Although some old trees have been removed, many aging, hazardous trees remain.  Many new trees will not be tall trees that provide a windbreak. Many new trees are dead because hand watering by volunteers is haphazard.
  • A landscape that looks messy now, but will look substantially worse when grant funding and volunteer commitments expire. 
  • A complex landscape that requires labor-intensive maintenance and can’t be maintained by the city in the long term.


The Sunset Blvd Biodiversity Master Plan is too ambitious.  It is trying to create a complex landscape that can’t be maintained without volunteer labor because the city doesn’t have the resources to maintain it.  The main goal for Sunset Blvd should be a landscape that reflects the preferences of the residents of the Sunset District, rather than the wishes of city bureaucrats. 

Assuming Sunset residents would like a safe windbreak, more hazardous trees must be removed.  Many are clearly dead and are obvious candidates for removal.  Replacement trees must be tall enough to provide a windbreak and they must be capable of tolerating salty ocean winds.  New trees must be watered weekly during the dry season for at least three years.  An irrigation system is required because hand watering is not reliable enough to ensure survival of new trees.

San Francisco’s General Plan (see policy 4.1) defines “biodiversity” as including both natives and non-natives.  A diverse landscape of natives and non-natives is more resilient because each has a different tolerance for changes in climate and environmental conditions.  A diverse garden also prolongs the blooming period, which serves pollinators best.  We visited the UC Berkeley Botanical Garden in early April to see a stunning display of blooming plants in the South African section of the garden.  On the same day, little was blooming in the California section of the garden. 

South African Collection, UC Berkeley Botanical Garden, April 8, 2023
North Coast, California Collection, UC Berkeley Botanical Garden, April 8, 2023

If new plantings were confined to the center of the wide medians, weeds could be mowed to serve as an ersatz lawn.  I walk in a local cemetery every day.  The “lawn” is 90% weeds.  It was dominated by oxalis from January to April.  Now purple alfalfa, clover, and English daisies are blooming.  The weeds are mowed and become a part of the lawn.  No one looks closely to distinguish weeds from grass.  The weedy lawn is rarely irrigated and is brown during most of the dry season.  It is now lush green after winter rains.  This is a sign (below) in one of our cemeteries that begs indulgence of visitors for this responsible response to the drought. 

St. Mary’s Cemetery, Oakland, California, January 17, 2023

There are several advantages to a weedy lawn.  It creates recreational space that can be used by residents in any way they choose, e.g., picnicking, playing ball or Frisbee, sunbathing, etc.  It does not require more water than the intensive planting on Sunset Blvd that is now watered by hand.  A weedy lawn provides flowering weeds that are useful to pollinators.  Most of all, it is a landscape that does not require labor intensive maintenance that the city cannot afford. 

The Sunset Blvd Biodiversity Master Plan is an example of short-term thinking that has not given enough thought to the long-term consequences of the choices it has made.  Residents of the Sunset District are living with the consequences of the short-term thinking that is typical of most public land management. 

A Necessary Nuisance: The Undervalued Functions of Non-native Aquatic Plants

Julian Burgoff

I am grateful to to Julian Burgoff for giving Conservation Sense and Nonsense this opportunity to publish his guest article that adds to our extensive collection of articles about the benefits of non-native plants and the damage done by herbicides to needlessly destroy them. Julian Burgoff is an avid bass angler and aspiring fisheries ecologist from western Massachusetts. He is currently a master’s student with the Massachusetts Cooperative Fish and Wildlife Research Unit at UMass- Amherst where he studies juvenile river herring age, growth and habitat use in coastal Massachusetts lakes and estuaries. He is passionate about lake ecology and the management of aquatic vegetation in lakes and hopes to work in a field related to lake conservation and warmwater fisheries management in the future.

Conservation Sense and Nonsense

Natural resource managers and scientists in the United States often use divisive, warlike language when referring to both terrestrial and aquatic plants they consider to be “invasive” species, devolving the complexity of ecological interactions into good vs evil rhetoric. Like terminology used by the US government to define groups such as undocumented immigrants, nonnative “invasive” species are often referred to by natural resource managers and scientists in this country as “alien” and “exotic,” causing “nuisance infestations” and economic and ecological “harm.” This demonization of non-native species is illustrated by the title of a seminar conducted last spring by the State of Connecticut’s Agricultural Experiment Station Invasive Aquatic Plant Program regarding the relatively recent proliferation of Hydrilla Verticillata in the lower Connecticut River:

Despite the hyper-negative perception cast upon non-native species, the reality is that non-native organisms often provide important ecosystem services in highly altered landscapes and waterbodies that are often completely overlooked and highly undervalued by the scientific community.

Aquatic plants harbor an immense amount of aquatic life in lakes, ponds, and rivers. They stabilize lake and river bottoms, sequester/cycle nutrients, provide oxygen, improve water clarity, and serve as important habitats for all aquatic life from small macroinvertebrates (larval insects) and zooplankton (free-floating microorganisms) to large predatory fishes. The aquatic plant communities in lakes and rivers of the United States are subject to sustained stress via anthropogenic disturbances to land and water. Land use changes including corporate agriculture, development and expansion of impervious surfaces, wastewater pollution and damming of rivers have all contributed to dramatic changes in aquatic ecosystems and their aquatic plant communities since the colonial invasion of the North American continent.

Non-native aquatic plants have long been blamed for their supposed negative ecological impacts to lake and river ecosystems. As a response to eutrophication (i.e. nitrogen and phosphorous enrichment from human activities), non-native aquatic plants can grow in extremely dense stands that are perceived to outcompete native aquatic vegetation, decrease water quality (e.g. lower dissolved oxygen), and reduce foraging efficiency for predatory fish. While this may be accurate at various spatial/temporal scales, the prolific growth of non-native aquatic plants also serves a multitude of benefits for lake and river ecosystems and the organisms that they support.

Non-native aquatic plants have a tremendous capacity to improve water quality in freshwater ecosystems. In tropical climates like Florida, floating plants such as Hyacinth (Eichhornia crassipes) and Water Lettuce (Pistia stratiotes) sequester nutrients from the water and produce allelochemicals (chemical compounds released by plants) that, along with physically shading areas of the water, can reduce harmful algal blooms.

Photo: Kevin Copple
Cyanobacteria bloom on Lake Hatchineha, Kissimmee, Florida

 In the northeast, Water Chestnuts (Trapa natans) provide similar ecosystem services in terms of shading, nutrient cycling, and competition with algal taxa. Non-native submerged aquatic plants such as Eurasian Milfoil (Myriophyllum spicatum) and Fanwort (Cabomba caroliniana) also compete with algae and cyanobacteria via allelopathy and physically collect suspended sediment and algae particles from the water column, improving water clarity.

Photo: Jody White
Eurasian Milfoil in a tidal tributary of the Potomac River
Dense Eurasian Milfoil in an urban central Massachusetts lake
Dense stands of Fanwort with holes/edges of clear water in an otherwise turbid, hyper-eutrophic Central Massachusetts lake

All of these plants provide habitat for a diverse array of macroinvertebrates and zooplankton, and thus contribute essential prey resources to feed the higher organisms up the food web like fishes.

Depiction of the interactions between plants, macroinvertebrates, zooplankton and fishes underneath beds of water chestnut on the Hudson River

Not all fisheries and aquatic ecologists are blind to the ecosystem services provided by non-native aquatic plants. Researchers following the recovery of submerged aquatic vegetation on the Potomac River and Upper Chesapeake Bay since the 1980s have documented the important role that hydrilla played in reestablishing water clarity and facilitating the regrowth of native aquatic plants such as Eel grass (Vallisneria americana) and Coontail (Ceratophyllum demersum). Long-term assessments of aquatic plant communities in these ecosystems failed to reveal the catastrophic impacts to native flora and fauna biodiversity claimed by the Connecticut Invasive Aquatic Plant Program. Similarly, a study regarding the impacts of hydrilla on the biodiversity of plants, fish and waterfowl in 39 Florida lakes conducted on multiple time scales found no significant effects on metrics of ecological health. A quote from the abstract of this article depicts the main findings:

“Our conclusions support the hypothesis that hydrilla in these Florida lakes has occupied a mostly vacant ecological niche and has not affected the occurrence or relative composition of native species of aquatic plants, birds, and fish.”

“Lack of exotic hydrilla infestation effects on plant, fish and aquatic bird community measures,” Mark Hoyer, et. al.

There seems to be a common pattern with aquatic plant “invasions”. Water quality suffers due to human activities which affect the ability for native plants to grow, opening a niche for more tolerant species to proliferate and this in turn often remediates conditions enough to allow native taxa to reestablish. Where native aquatic plant communities remain intact and water quality remains high, the degree to which “invasion” of non-native aquatic plants occurs is often buffered by the integrity of the existing native plant communities. The notion that non-native aquatic plants enter an ecosystem and completely overtake the native plant community is rarely, if ever, an actual phenomenon realized in nature. In my view, the trouble comes when humans seek to selectively intervene with species interactions and try to control aquatic plant communities with quick fixes like herbicides and algicides as band-aids to cover up the consequences of poor water quality. These “management” efforts often result in a net loss of ecosystem services, biodiversity, habitat, and water quality.  The pictures below illustrate this phenomenon.

Variable-leaf Milfoil (Myriophyllum heterophyllum) growing amongst native Yellow Water-lily (Nuphar lutea) in an eastern Massachusetts lake
Variable Milfoil left to rot after a chemical herbicide treatment in a neighboring eastern Massachusetts lake

Where I live in Massachusetts there are dozens of small ponds and lakes that are sprayed with herbicides annually to treat “nuisance” aquatic vegetation. Most aquatic plant “control” here is driven by the desires of lakefront property owners who are concerned with their property values and want to transform the lakes they live on into swimming pools (full of toxic cyanobacteria, I suppose). A select few private lake management companies (e.g., Solitude Lake Management) enjoy a monopoly over the lake management market in this region and are endorsed by herbicide manufacturers to put chemicals into our water in the name of ecological “restoration”. Unfortunately, there is often extremely limited pre and post water quality monitoring, and almost never in-depth pre and post monitoring for impacts to indicators of biotic health (native plant communities, zooplankton/macroinvertebrate communities, fish etc.) following these treatments.

 While this issue is not studied nearly enough by independent scientists (i.e. those not representing institutions funded by chemical manufacturers), numerous studies have shown that lake herbicide treatments can have negative impacts to water quality, native plant communities, zooplankton communities, fish and wildlife. I have witnessed firsthand the negative consequences of herbicide use to “control” non-native aquatic plants ever since I was a kid. I’ve seen numerous lakes with abundant milfoil populations turn from crystal clear water to pea soup, with dense cyanobacteria blooms following chemical treatment.

Some of the healthiest lakes are those which have never been subjected to large-scale herbicide treatments. One such lake, Lake Bomoseen, is one of the most important fisheries in the state of Vermont, offering trophy Brown Trout, Largemouth Bass and Smallmouth Bass angling opportunities. Since the 1980s, the lake has supported an abundant population of Eurasian Milfoil. An excellent example of the ecosystem services achieved by allowing species interactions to occur unmolested over time, Lake Bomoseen supports an extremely healthy native aquatic plant community in addition to the dense stands of Eurasian Milfoil present around the lake. In 2022, the Lake Bomoseen Association, comprised of select individuals who own property around the lake, requested a permit from the Vermont Department of Environmental Conservation for the use of an herbicide ProcellaCOR to treat the entire littoral zone (i.e. the area of the lake where plants grow) of the lake over a 3-year period. This spurred a tremendous amount of public dissent. Lakefront property owners, local anglers, and hundreds of Vermont citizens concerned with the use of chemicals in the lake have united and made their voices heard on the issue. The Vermont Fish and Wildlife Department submitted a review of the treatment application to the Vermont DEC, stating that the proposed treatment was a threat to the health of the lake and the integrity of its fish populations. An excerpt from the review sums up the position of the VT Fish and Wildlife on this proposed treatment:

“Lake Bomoseen supports high-quality sportfish fisheries that rely on a diverse healthy aquatic plant community, which may be harmed by wide-scale application of pesticide, thus impacting these sportfish populations and the public benefits they support. The pesticide application at the scale proposed presents a risk to fishing as a public benefit.”

Vermont Fish and Wildlife

The proposal is still under review by the VT DEC, which if approved, would be the largest lake-wide herbicide treatment ever conducted in the state of Vermont. More information about this issue and how you can support the folks fighting to stop this treatment can be found here.

My observations of aquatic plant communities and their importance as habitat for fish have led me to pursue a career in fisheries and aquatic ecology. Before I had ever read a single piece of scientific literature, I had internalized many of the complex interactions between fish and aquatic plants based off of intuition derived from thousands of hours of on the water experience fishing in eutrophic, heavily vegetated Massachusetts ponds and lakes. To this day I am obsessed with fishing in thick aquatic vegetation. In the summer months on a hot sunny day I will actively seek out lakes with the densest aquatic plants I can find to chase after big bass hiding in the matted cover. I share this passion with thousands of anglers across the country.

Native aquatic plants can grow in dense stands, too. This is a cavernous mat of Elodea canadensis over +/- 9ft of water in a bay on southern Lake Champlain
Releasing a Largemouth Bass extracted from the canopy pictured above

Next time you go to your local lake or river, spend some time looking at the aquatic plants that inhabit that body of water. If you have the opportunity, go under the water to observe how fish utilize and interact with stands of aquatic plants. Notice all the life that resides within the plants and try to appreciate the organisms that you encounter, regardless of where in the world they may have originated.

Julian Burgoff
Amherst, MA

California’s “Sustainable Pest Management Roadmap” is a 25-year poisonous pathway

California’s Department of Pesticide Regulation (DPR) has published a draft of a policy that would replace its Integrated Pest Management policy with a Sustainable Pest Management (SPM) policy that is different in name only.  SPM makes a commitment to continue using pesticides in California until 2050, and by implication, beyond.  It makes NO commitment to reduce pesticide use or reconsider the current targets of pesticide applications.  It claims that the health hazards and damage to the environment will be reduced by identifying “Priority Pesticides” for possible substitution or “eventual elimination.”  It doesn’t commit to identifying any specific number of dangerous pesticides nor does it provide specific criteria for selecting these dangerous products.  It claims that increased testing and development of new products will result in safer products and puts these judgments into the hands of “stakeholders” with “experiential and observational knowledge” rather than scientists with expertise in soil science, endocrinology, toxicology, epidemiology, biology, botany, horticulture, etc.  The “stakeholder” committee that wrote the SPM proposal for urban areas included the manufacturer of pesticides and other users and promoters of pesticides. 

That’s not an exhaustive list of the many faults of SPM and the dangers that lurk in it.  I hope you will read it yourself and consider writing your own public comment by the deadline on Monday, March 13, 2023, at 5 pm.  The document is available HERE.  It’s less than 100 pages long and it is a quick read because it is basically a collection of bullet-points.

This is how to comment:  “DPR is accepting public comments to inform the prioritization and implementation of the Roadmap’s recommendations through March 13, 2023 at 5 p.m. Comments can be shared in writing to or by mail to the department at 1001 I Street, P.O. Box 4015, Sacramento, CA 95812-4015.” Please note that Department of Pesticide Regulations is not offering revisions, only “prioritization and implementation.” 

My public comment on California’s “Sustainable Pest Management Roadmap”

 A summary of my public comment is below.  A link to the entire comment is provided at the end of the summary:

Public Comment on
“Sustainable Pest Management Roadmap”
(AKA “Pathway to poisoning the environment for another 25 years”)

My public comment is focused on pesticide use in urban areas because of my personal experience and knowledge of pesticide use where I live.  These are the broad topics I will cover in detail with specific examples later in my comment:

  • Since glyphosate was classified as a probable carcinogen by the World Health Organization in 2015 and the manufacturer of glyphosate settled 100,000 product liability lawsuits by awarding $11 billion to those who were harmed by glyphosate, public land managers have been engaged in the process of substituting other, usually equally or more dangerous herbicides for glyphosate to deflect the public’s concerns.  The Sustainable Pest Management Roadmap (SPM) formalizes this process of substitution without addressing the fundamental problems caused by pesticides. 
  • SPM endorses the status quo that exists now.  Affixing the word “Accelerating” to SPM is an extreme case of double-speak that deliberately obscures, disguises, distorts, or reverses the meaning of words.  SPM ensures that toxic pesticides will be used in California for more than 25 years, to 2050, and likely beyond.  SPM therefore accelerates the damage to the environment that is occurring now.  Given that climate change will enable the movement of more pests into areas where they are now suppressed by weather, greater use of pesticides should be anticipated so long as the underlying issue is not addressed.
  • The underlying issue is that pests have been identified for eradication that in some cases cannot be eradicated and in other cases should not have been identified as pests either because they are innocuous or because of the valuable ecological functions they perform.  The key question that SPM does not address is whether pesticide use is truly necessary in the first place.  Unless we focus on whether a pesticide is actually necessary, all other issues are merely window dressing for perpetual pesticide use. 
  • SPM proposes to identify “Priority Pesticides” for possible substitution without any clear definition of “Priority Pesticides,” a process that is ripe for manipulation. Given the substitutions that are occurring now, we cannot assume that further substitutions would be less toxic. SPM puts the classification of “Priority Pesticides” into the hands of “stakeholders” without clearly identifying who stakeholders are.  SPM says “stakeholders” were involved in the development of the proposed policy.  Those stakeholders included only users and promoters of pesticide use.  There was no representation on the Urban Sub-Group of organizations such as Californians for Pesticide Reform, California Environmental Health Initiative, Beyond Pesticides, Center for Environmental Health, Environmental Working Group, etc.  Nor was there any visible expertise in the fields of science that are capable of analyzing and evaluating the impact of pesticides, such as soil science, endocrinology, toxicology, entomology, botany, biology, or horticulture.  SPM ensures that this exclusion will continue during the implementation phase by suggesting that “experiential and observational” knowledge should be represented on an equal footing with undefined “science.”  The word “science” is being used and abused by advocates for pesticide use who dangle it as a magic talisman, conferring fraudulent credibility. 

My entire public comment is available here:

The Oxalis Obsession

As a long-time reader of Jake Sigg’s Nature News, I am very familiar with his passionate crusade against Oxalis pes-caprae.  When oxalis appears in the landscape in January, Jake gears up his campaign again. This year the Westside Observer published an article by Jake about oxalis that reaches a new level of urgency and asks land managers to increase their use of herbicides to kill the plant.

In the past, Jake has advised careful and relentless hand-pulling of oxalis with its bulb intact.  Now he acknowledges that hand-pulling is useless to eradicate oxalis.  Although herbicides have been used on oxalis in San Francisco’s parks for 25 years, Jake now wants MORE herbicides to be used. Over 20% of all herbicide spraying by the Natural Resources Division (NRD) of the Recreation and Park Department was applied to kill oxalis in “natural areas” in 2022. NRD sprayed oxalis 35 times in 2021 and 38 times in 2022.

Spraying Garlon on Twin Peaks in San Francisco, February 2011

From January to March, virtually all the herbicides sprayed by NRD in the so-called “natural areas” were sprayed on oxalis.  If it were possible to eradicate oxalis with herbicide, why is there more oxalis now than there was 25 years ago, when NRD (then known as the Natural Areas Program) started spraying herbicides in the “natural areas?”  A lot of herbicide has flowed under the bridge in the past 25 years, but oxalis thrives. What is the point of pouring more herbicide under the bridge of sighs?  We’re pouring more fuel on the fire with nothing to show for it. 

One of many pesticide application notices on oxalis in Glen Canyon Park in February 2023.

The University of California Integrated Pest Management Program explains why it’s not possible to eradicate Oxalis pes-caprae with herbicides: “Several postemergent herbicides including triclopyr and fluroxypyr (selective for broadleaf plants) and glyphosate and glufosinate (nonselective) effectively kill the top growth of this weed but are harmful to most ornamentals, so be careful these herbicides don’t drift onto desirable plants. These herbicides don’t kill the bulbs, and regrowth from bulbs should be expected.” In other words, you can kill the above-ground top growth and other non-target plants in the vicinity, but you won’t kill the oxalis. 

Chemical Warfare?

On one hand, Jake urges public land managers to escalate chemical warfare against oxalis.  On the other hand, he accuses oxalis of “chemical warfare” (AKA allelopathy), secreting chemicals that kill other plants. This accusation is pure speculation on Jake’s part.  He offers as “evidence” of his speculation that after oxalis dies back in April “we’re left with bare ground for the rest of summer and autumn.”  He ignores the obvious fact that annual spraying of gallons of herbicide on oxalis in the “natural areas” could be causing the bare ground. It has apparently not occurred to him that many herbicides are non-selective, killing everything they touch, not just targeted plants. And those herbicides that claim to be selective are very mobile in the soil, capable of killing adjacent plants through their roots.  If you don’t want to see bare ground, don’t spray herbicides!

Jake asks for more research on how oxalis interacts with other plants in his article published by Westside Observer. He is apparently unaware of the research that has been done by scientists at University of Montana to address the question of how competitive oxalis is in plant communities that include native plants:  “Oxalis is a poor competitor. This is consistent with the preferential distribution of Oxalis in disturbed areas such as ruderal habitats, and might explain its low influence on the cover of native species in invaded sites.

The study explains why oxalis does not suppress the growth of other plants, including natives.  Oxalis makes more phosphorous available in the soil, which essentially acts as a fertilizer for other plants“These results are consistent with our field data and suggest that Oxalis may improve P availability in the field.”

This study was published in 2007.  It found that Oxalis pes-caprae does not suppress the growth of other plants and, in fact, increases nutrients in the soil.  Jake apparently doesn’t know about this study and related studies that found that pollinators are as interested in O. pes-caprae as they are in native plants.

Jake’s accusation that oxalis is waging “chemical warfare” against native plants does not come out of nowhere.  The same accusation was used against eucalyptus trees for decades until a definitive empirical study proved that eucalyptus is not allelopathic.  The California Invasive Plant Council removed that accusation from its evaluation of Blue Gum eucalyptus in 2015 (along with the accusation that eucalyptus kills birds).  As the readers of Jake’s Nature News know, his hatred of eucalyptus is second only to his hatred of oxalis.  There was never evidence that eucalyptus is allelopathic and there is no evidence that oxalis is allelopathic.

Does biodiversity justify poisoning nature?

Jake justifies his crusade against oxalis based on his belief that its existence threatens biodiversity.  Since there is no evidence that oxalis kills other plants, there is no reason to believe its existence threatens biodiversity.  

Jake also asks us to include only native plants in the measure of biodiversity, but he is alone in that belief.  Scientific measurements of biodiversity include all species of plants and animals, whether considered native or non-native.  The Recreation and Open Space Element of San Francisco’s General Plan explicitly acknowledges that both native and non-native plants contribute to biodiversity:  “Parks and open spaces in San Francisco include both native and non-native species, both of which can contribute to local biodiversity.” (Policy 4.1, Recreation and Open Space of San Francisco General Plan)

Jake ups the ante against oxalis by claiming that wildlife requires solely native plants, a fundamental tenet in native plant ideology.  Again, this claim is unsupported by evidence.  As Professor Art Shapiro (UC Davis) says in his Field Guide to Butterflies of the San Francisco Bay and Sacramento Valley Regions, “Most California natives in cultivation are of no more butterfly interest than nonnatives, and most of the best butterfly flowers in our area are exotic.”

coyote hunting in oxalis field. Copyright Janet Kessler

On one hand, Jake claims that oxalis deprives birds and other foragers of food.  On the other hand, Jake acknowledges that oxalis is foraged by gophers and scrub jays (based on one observation).  Jake wants it both ways because that serves his purpose. 

If native plants were any benefit to wildlife, that benefit is quashed by the widespread use of herbicides being used in the “natural areas.”  For example, Himalayan blackberries are an important source of food for birds and other wildlife in San Francisco’s parks and are also eaten by children visiting the parks.  The blackberries are routinely sprayed with herbicides in the so-called “natural areas.”  Wildlife is exposed to the herbicides and they are also deprived of important sources of food.

A recent survey of 24,000 gardens in the UK found that pesticide use had a significant effect on bird life. The study found that gardens that used pesticides had fewer species of birds than similar gardens that did not use pesticides:

“Pesticide spraying impacted the positive effect [surrounding habitat quality] had on bird richness. Specifically, ‘species richness [number of species] increases with the surrounding quality, both for gardens that do not use pesticides and for gardens that applied pesticides, but this effect is significantly less strong when pesticides are applied’ the study indicates. Scientists zeroed in on three active ingredients: the weed killer glyphosate, the neonicotinoid insecticide acetamiprid, and the synthetic pyrethroid deltamethrin as resulting in the most damaging pesticide impacts to bird species’ richness.” Note that the study’s definition of “surrounding habitat quality” made no distinction between native and non-native plants.  The British are not strong supporters of native plant ideology. 

Nativists keep using huge quantities of herbicide to kill vegetation they don’t like, while also claiming that their eradication projects benefit birds. This is a fundamental contradiction. Their eradication projects are harmful to birds and other creatures that live in our parks and open spaces.

Jake’s Lament

In his article, Jake laments that people are accepting changes in the landscape because they don’t remember what the landscape looked like 100 years ago.  His “baseline view” of what landscapes should look like is much further in the past than most people’s memories of the landscape. 

The climate has changed significantly in the past 100 years.  When the climate changes vegetation changes.  We should welcome the changes because they are required for the survival of any landscape.  When the climate changes, plants and animals must move, adapt, or die.  The changing landscape is an indication that plants are adapting to changing conditions. 

We cannot stop evolution, nor should we try.  Herbicides are a futile attempt to stop evolution.  Herbicides cannot stop evolution, because plants evolve a resistance to them.  After 25 years of constant herbicide use in San Francisco’s parks and open spaces, we should assume that they are less effective every year. 

While San Francisco’s Recreation and Park Department has significantly reduced its use of herbicides since 2010, the Natural Resources Division that is responsible for the “natural areas” has not. Natural Resources Division is now using more herbicides than the rest of the parks. Source: San Francisco IPM Program, Department of Environment

What does “restoration” mean?

I welcome comments on my website because I often learn from them.  This comment on a recent post inspired me to think about why I often put the word “restoration” in quotation marks when describing projects that are more destructive than constructive:

Oh my, we are back to putting quotes around words we don’t like. An excerpt from this article:

“Many ecological studies and associated “restoration” projects adopt the same viewpoint that destruction is a justifiable method of studying and “restoring” ecosystems. “Restoration” projects often begin by killing all non-native plants with herbicides before attempting to create a native landscape.”

Often? We do a fair amount of underburning around here, primarily to “restore” ecosystem structure and function in mixed conifer. Of the burns I have been involved with, not one involved herbicides and pesticides. I think you put the lie to your own article by this one exaggeration. I suspect if I bothered to look I would find many others.

This is my reply to this comment:

When the word restoration is used appropriately, it is a powerful, positive word.  There is a multitude of potential projects in California that would be restorative.  Here is a brief list:

Superfund Sites in California

Prescribed burns are currently popular and some don’t use herbicides before burning, but they are NOT a panacea.  Many prescribed burns have become destructive wildfires.  Here are two presentations made at the October conference of the California Native Plant Society that were critical of the over-reliance on prescribed burns:

Source: Jon F. Keeley, CNPS Conference, October 2022
  • Dr. Jon Keeley is a respected fire scientist with US Geological Service with expertise in chaparral ecosystems.  He explained that 60% of native chaparral species (notably manzanita and ceanothus) are obligate seeders that do not resprout after fire and therefore depend on their dormant seed bank for regeneration.  In recent decades the fire interval in chaparral has decreased due to climate change and associated drought.  In many places the fire interval has become too short to establish the seed bank needed for regeneration.  In those places Dr. Keeley has observed vegetation type conversion to non-native annual grasses.  Dr. Keeley Is concerned that vegetation type conversion from forests in some cases and shrublands in others to non-native annual grassland may be the result of shortening fire intervals further “because of the upsurge in state and federal programs to utilize prescription burning to reduce fire hazard.” 
  • Another presentation about a 20-year effort to convert non-native annual grassland to native grassland using prescribed burns at the Santa Rosa Plateau Ecological Reserve reported their failure: “Non-native grass cover significantly decreased after prescribed fire but recovered to pre-fire cover or higher one year after fire.  Native grass cover decreased after prescribed fire then recovered to pre-burn levels within five years, but never increased over time.  The response of native grass to fire (wild and prescribed) was different across time and within management units, but overall native grass declined.” The audience was audibly unhappy with this presentation.  One person asked if the speaker was aware of other places where non-native grass was successfully converted to native grass.  The speaker chuckled and emphatically said, “NO.  I am not aware of any place where native grasses were successfully reintroduced.” 

When describing projects that are more destructive than constructive, I put the word “restoration” in quotes.  I stand by that choice.

Projects that are truly restorative

Days after responding to this comment, the New York Times published an article about the successful effort to clean up the New York City harbor that deserves to be called a restoration:

“Fifty years ago, Congress voted to override President Richard Nixon’s veto of the Clean Water Act. It has proved to be one of the most transformative environmental laws ever enacted.

“At the time of the law’s passage, hundreds of millions of gallons of raw sewage was dumped by New York City into the Hudson River every day. This filth was compounded by industrial contaminants emptied into the river along much of its length. The catch basin for all of this was New York Harbor, which resembled an open sewer. At its worst, 10 feet of raw human waste blanketed portions of the harbor bottom, and certain reaches held little or no oxygen to sustain the life of its fishery. Trash floated among oil slicks.

“Health advisories against eating fish from the Hudson remain, but its ecology has largely recovered, thanks to the law, which imposed strict regulations on what could be discharged into the water by sewage treatment plants, factories and other sources of pollution….”

The NYT article also describes how many animal species benefitted from the reduction in pollution in New York City’s harbor.

NYT also published an article about the pollution of the water surrounding Cape Cod that is destroying that ecosystem. 

“The algal explosion is fueled by warming waters, combined with rising levels of nitrogen that come from the antiquated septic systems that most of the Cape still uses. A population boom over the past half-century has meant more human waste flushed into toilets, which finds its way into waterways.

“More waste also means more phosphorus entering the Cape’s freshwater ponds, where it feeds cyanobacteria, commonly known as blue-green algae, which can cause vomiting, diarrhea and liver damage, among other health effects. It can also kill pets.

“The result: Expanding aquatic dead zones and shrinking shellfish harvests. The collapse of vegetation like eelgrass, a buffer against worsening storms. In the ponds, water too dangerous to touch. And a smell that Ms. Fisher characterizes, charitably, as “earthy.”

“Together, the changes threaten the natural features that define Cape Cod and have made it a cherished destination for generations.”

Cape Cod. Source: NASA

This an example of the many missed opportunities to restore the environment.  Instead of addressing the sources of pollution, such as leaky septic tanks and sewage systems, we invest in projects that contribute to pollution by spraying harmless vegetation with herbicides, killing harmless animals with pesticides and contributing to air pollution by burning vegetation. 

Closer to home, the recent torrential rain soaking California is a reminder of our inadequate sewer systems now overflowing from storm drains into city streets and being dumped into the ocean when the drainage gets that far.   San Francisco’s antiquated sewage system is an extreme case.  When it was built, it funneled storm runoff from city streets into the city’s sewer system, combining residential sewage waste with storm water runoff.  When it rains heavily, San Francisco’s sewage system is not capable of treating the increased flow. Such systems have been illegal for decades, but San Francisco has not made the necessary improvements to its sewer system.  As the SF Chronicle reports, city streets are now flooded with a toxic mix of rain water and human sewage. 

“Restoration” is not a dirty word when used to describe projects that reduce pollution.  When projects contribute to pollution they cannot legitimately be called “restorations.” 

Wild by Design: A history of ecological restoration in the U.S.

“This is a superb book. Laura Martin’s research takes us where no restoration literature has gone before, asking, ‘Who gets to decide where and how wildlife management occurs?’ Martin tackles this question with unmatched clarity and insight, illuminating the crucial discussions we must have to secure a future with thriving natural species and spaces.”—Peter Kareiva, President and CEO, Aquarium of the Pacific

The author of Wild by Design, Laura J. Martin, is a professor of environmental history at Williams College.(1) She has written a comprehensive history of ecological restoration in the US that is consistent with my own observations of the restoration industry in the past 25 years.  It’s a story of the gradual transition from a conservation ethic to a preservation ethic and finally to the restoration ethic that we see today.  The story is punctuated by milestone federal laws and actions that facilitated the transition.  Environmental non-profits and academic ecologists used those laws to professionalize and monetize the restoration industry that exists today. 

By the end of the 19th Century, the public began to react to the environmental degradation caused by unregulated resource extraction.  In 1902, a survey of naturalists around the country determined there were 1,143 bison left in the country; virtually all were in captivity.   The American Bison Society was founded in 1905 in reaction to the disappearance of bison in America.  Their activism led to the creation of federal game reserves on former Indian reservations where captive bison were introduced.  The game reserves were the model for the National Wildlife Refuge system that was greatly expanded by President Teddy Roosevelt.

A photograph from 1892 of a pile of American bison skulls in Detroit, Michigan waiting to be ground for fertilizer or charcoal. (Photo Wikimedia Commons)

The creation of the Wild Flower Preservation Society (WFPS) in 1901 was modeled on the successful campaign of the Audubon Society to save birds killed to serve as ornaments on fancy hats.  It was as much a campaign to shame women into abandoning the fashion fad as it was an effort to legally ban the practice.  Likewise, the Wildflower Preservation Society applied social pressure.  They were critical of organized excursions to visit wildflowers because they picked and trampled the wildflowers.  WFPS said that “Weddings are a new menace to our native plants” because of their use of wild flowers. Their criticism was initially aimed at their own community, but “it moved toward policing the behavior of so-called new immigrants to the United States—especially children.”  The moralistic scolding by these early native plant advocates was a preview of the finger-wagging now aimed at those who choose to plant a diverse garden. 

These advocacy organizations are precursors to the many environmental non-governmental organizations that are influential in pressuring government to invest in ecological restorations today.

Conservation and Preservation

The goals of conservation and preservation are similar, but some differences were observable in the past 200 years.  Both ethics are committed to protecting the environment, but conservation allows the sustainable use of natural resources while preservation protects nature from use.  The presidencies of both Teddy and Franklin Roosevelt were committed to conservation. 

Teddy Roosevelt created the US Forest Service based on the premise that government can and should regulate public lands to manage natural resources.  Franklin Roosevelt’s conservation programs were based on the same principle, but were motivated by the economic emergency of the depression as well as the environmental disaster of the Dust Bowl in the Midwest.  The Civilian Conservation Corp (CCC) was created to provide jobs as well as to plant a “shelter belt” of trees across the Midwest of the country as a windbreak to stop dust storms (and many other projects).  Ecologists were critical of CCC projects because they expanded recreational opportunities and put “a stamp of man’s interference on every natural area they invade.” They preferred to exclude humans and their activities from nature. This is another early indicator of the conflicts between preservation and conservation that persist to the present day.

Sharp Park, Pacifica, CA. Photo by Erica Reder, SF Public Press

Government investment in ecological research

Ecological research in the United States was fundamentally altered after World War II, which ended with the beginning of the atomic era.  Atomic bombs were dropped on Japan to end the war without much thought given to the consequences.  After WWII, the federal government made big investments in science, creating the Atomic Energy Commission and the National Science Foundation, which funded ecological research to study the impact of radiation on the environment and those who live in it.  Conservation Sense and Nonsense published an article about those studies and the impact they had on ecological research. 

These studies legitimatized destruction of ecosystems to study effects of the destruction and the concept was expanded from radiation to pesticides in the 1960s.  They also provided funding to the academic profession of ecology that was small and is now enormous.  The dependence of ecological studies on government funding remains to this day and government funding of ecological projects has created the restoration industry that now extends far beyond academia.  Destruction of existing habitat is still considered the prerequisite to restoring a historical landscape.  Often, destruction is the first and only stage of the project because of the persistent fantasy that the native landscape will regenerate without further help. 

In the late 1960s Daniel Simberloff tented and fumigated 6 mangrove islands off the eastern short of Florida with methyl bromide to kill all life on the islands.  The objective of the project was to study how long it would take to repopulate the islands with insects.

From Conservation to Restoration

The post-war economic boom of the 50s and 60s greatly increased the impact of human activities on the environment.  The federal government built a vast highway system that fragmented and disrupted ecosystems.  We built huge dams, and channeled riparian ecosystems.  Open space was rapidly covered by housing and industrial development.  Wetlands were drained and filled with rubble to create more land.

People who cared about the environment began to react to the loss of nature and wildlife that lives in nature.  Although Aldo Leopold is idolized by the native plant movement, his concern about the degradation of nature was primarily for wildlife.  His interest in vegetation was as habitat for wildlife.  He was opposed to government programs devoted to killing animals perceived as predators of game animals because he believed that wildlife is best served by expanding their habitat.  In fact, he was opposed to the expansion of government’s role in conservation because “he believed restoration would be most efficient and effective if pursued by private citizens.” He did not prefer native plants because “Farmers had the opportunity to conserve plants such as ragweed and foxtail (an introduced grass), ones ‘on which game, fur, and feather depend for food.’”  In other words, in the 1940s one of the icons of the native plant movement knew that wildlife is not dependent upon native plants for food.  One wonders if native plant advocates have actually read Leopold’s treatise, A Sand County Almanac. 

Aldo Leopold’s son, Starker Leopold, had as much impact on conservation in the United States as his father.  In 1963, he published the Leopold Report that changed the direction of conservation in the National Park Service.  The Leopold Report recommended a goal for national parks of maintaining historical conditions as closely as possible to those of “primitive America.”  When the Leopold Report was adopted as official policy by the National Park Service in 1967, it committed NPS to restoring park lands to pre-settlement conditions. NPS officially changed this policy in 2021, but we don’t see any change locally in their projects because NPS is decentralized and local parks are autonomous.

Restoration Goals

Professor Martin says that “historical fidelity did not become a widespread restoration goal among ecologists and environmental organizations until the 1980s.”  The arrival of Columbus in the new World in 1492 was arbitrarily selected as the date after which all new plant species were “deemed nonnative, unwanted reminders of human (colonist) presence and activity.”  On the West Coast, 1769 is the equally arbitrary date to confer non-native status because it is the date of the first Spanish expedition to California. 

Many now question the goal of replicating historical landscapes.  After 40 years of effort, there is a growing recognition that it is not a realistic goal, especially in a rapidly changing climate.  The Society for Ecological Restoration has changed its definition of ecological restoration from “the goal of intentionally altering a site to establish a defined, indigenous, historic ecosystem” in 1990 to “the process of assisting the recovery of an ecosystem that has been degraded, damaged, or destroyed” in 2002.  Try telling that to the restorationists on the ground who are still trying to eradicate naturalized non-native plants that have been here for nearly 200 years.  Non-native annual grassland in California is a case in point. It has been repeatedly burned, mowed, plowed, and poisoned for 25 years without any visible progress toward native perennial grassland.   

Blaming non-native species

Around the same time that historical fidelity was identified as the goal of “restorations,” land managers and ecologists decided that the existence of non-native species is the main threat to native species.  I suppose the “logic” was that the main difference between historical landscapes and present landscapes is the existence of non-native species.  Concern about non-native species spread among federal agencies such as the National Park Service and The Nature Conservancy (TNC) began aggressive campaigns to kill non-natives, “which were newly framed as the main threat to wild species…nativity would become a precondition to wildness—of plants and animals both.”   TNC’s methods have become increasingly deadly and destructive: using fire and herbicides to kill plants, poisoning honeybees, aerial hunting of sheep, pigs, and goats.  As a former donor to TNC, their methods finally became intolerable to me.

Professor Martin believes that the identification of non-native species as the scapegoat was not based on experimental evidence, but merely a description of the strategies used by public land managers, as well as The Nature Conservancy.  Non-native species were a convenient scapegoat because they were easily identified and were an easy substitute for identifying and remediating the underlying conditions causing so-called “invasions.”  “Although the role of invasive species in native species extinction has since been challenged by some ecologists, the influence of this fear on species management has been enormous…The US federal budget for invasive species management increased by $400 million between 2002 and 2005, for example.”   

Endangered Species Act

The Endangered Species Act (ESA) was passed in 1973, along with companion laws such as the National Environmental Protection Act and others.  These federal laws created more funding opportunities for ecological projects as well as the legal justification for ecological restoration projects.

Federal laws permit the reintroduction of legally protected plant and animal species to places where they no longer exist.  The ESA confers the same protections for reintroduced species as it does for naturally occurring species.  Such reintroductions have become a tool for the restoration industry.  I have seen that strategy used in the San Francisco Bay Area.  If we had not been successful in preventing the reintroduction of a legally protected turtle, it would have justified the destruction of the non-native forest in my neighborhood park because the turtle requires unshaded nesting habitat within 500 feet of the water source in the park. The park remains largely forested because that is one of the few battles we have won in 25 years. Reintroduced, legally protected species are the Trojan horses of ecological restorations.

Compensatory mitigation is an equally powerful tool for the restoration industry.  Federal law requires an Environmental Impact Statement (EIS) for projects that will have a significant impact on the environment, such as big developments like building Disney World in Florida.  Disney World was built on an enormous wetland that was lost by the development of the park.  The EIS for the project agreed that the impact would be great, but it “mitigated” the impact by requiring Disney to fund the creation of a new wetland in a distant location.   

The funding generated to create fake wetlands built a new industry of commercial companies to design and build them.  Academic restoration ecologists questioned the functional equivalency between created and natural wetlands:  “’however accurate [the Comprehensive Everglades Restoration Plan] is the restored community can never be authentic.’”  The tension between commercial and academic restorationists continues today.

The Society for Ecological Restoration published findings that mitigation wetlands were not functionally equivalent to the wetlands they were meant to replace.  In Florida only half of the promised mitigation projects were actually built. Those that were built were colonized by “undesirable plant species” such as cattail and melaleuca in 32 of 40 projects.    

Projects that earn carbon credits are creating the same opportunities to generate funding for restoration projects in distant locations.  The Nature Conservancy was successful in defining carbon offsets as an international market when the Kyoto Protocols were signed in 1997.  They understood that a reforestation project would be cheaper in Costa Rica (for example) than a comparable energy efficiency project in the US.  Such distant projects don’t benefit those in the US who now have a power plant in their backyard that is being offset by a forest in Costa Rica. 

It’s a game for those who know how to play.  I have witnessed local examples in the Bay Area.  An oil spill in the bay generated millions of dollars of compensatory damages to fund unrelated “restoration” projects.  How does planting eel grass compensate for hundreds of birds killed by the oil spill?  When the San Francisco airport expanded runways, the airport had to pay compensatory mitigation that funded the restoration of native plants at India Basin in San Francisco that hardly compensates for the increased air traffic enabled by the new runway.   


Professor Martin is surprisingly frank about the future of ecological restoration in America:

“Whatever paths restorationists choose, restorations must happen in tandem with other changes in human behavior.  If we don’t reduce the ongoing harms of racism, fossil fuel burning, overconsumption by the wealthy, and toxic industrial chemicals, restoration will offer no more than a temporary repair, a way to move a problem to some other place or time.”

I would go one step further in my assessment of the restoration industry.  I would say that the methods used by restorationists are directly contributing to environmental degradation. 

Professor Martin asks the right questions in her concluding chapter:  “Who benefits from restoration?  Who is harmed?”  Those who earn their living in the restoration industry are the primary beneficiaries. According to a 2015 study entitled “Estimating the Size and Impact of the Ecological Restoration Economy,” environmental regulation has created a $25 billion-per-year restoration industry that directly employs more people than coal mining, logging or steel production.  Given recent investments in restoration projects of billions of dollars by California and federal infrastructure funding, this figure is undoubtedly an underestimate. 

Who is harmed?  Wildlife and humans are harmed by the destruction of useful habitat with herbicides.  Harmless animals and plants are killed because they have been arbitrarily classified as “invasive.” And all Americans are harmed by the waste of public funds that could be used to benefit society and/or the environment. 

(1) Laura J. Martin, Wild by Design:  The rise of ecological restoration, Harvard University Press, 2022.  All quotes are from this book.

The Destructive Origins of Ecological Field Studies

Laura J. Martin is an environmental historian at Harvard University.  She wrote two articles (1,2) about the origins of ecological field studies that might help explain the destructive methods still used today by some ecologists.  Professor Martin “contends that the history of ecosystem science cannot be separated from the history of nuclear colonialism and environmental devastation in the Pacific [Nuclear Testing] Grounds” (2)

When the US dropped two atomic bombs on Japan in 1945, little thought was given to the consequences of atomic bombs because ending the war in the Pacific was the only consideration.  Japan surrendered to the US less than one month after the bombs were dropped, effectively ending World War II. 

Few doubt that the use of atomic weapons was instrumental in ending World War II.  After the war, there was a more sober effort to determine the consequences of using atomic weapons.  Some believed that nuclear weapons might replace conventional warfare.  Others wanted to understand the impact on life on the planet before making such a momentous decision.  This effort was focused on practical considerations such as the impact on the world’s fisheries and food supply.  The objective of their initial studies was less concerned about long-term consequences for the environment such as the duration of impacts on living creatures and the environment in which they live.

The US federal government invested heavily in the sciences after World War II. The Atomic Energy Commission (AEC) was established in 1946 and the National Science Foundation (NSF) in 1950.  The availability of federal grant funding for academic institutions “dramatically reconfigured the relationships among federal, academic, and corporate spheres.” (2) Increased federal funding greatly increased the number of academic research projects.

Between 1945 and 1970, the US detonated 105 nuclear weapons. The Atomic Energy Commission and later the National Science Foundation paid academic ecologists to conduct field studies at the test sites to determine the impact on animals. 

In 1963 the US, Soviet Union, and Great Britain signed a Partial Test Ban Treaty that prohibited all non-wartime detonations except for those done below ground.  Testing of the effects of radiation by academic scientists continued because the AEC mass produced radioisotopes and distributed them to American institutions.  Scientists were no longer constrained to field sites where atomic bombs had been detonated.

“Thus began a period in which ecologists purposefully destroyed ‘ecosystems’ to study how they recovered.”

Laura Martin, “The World in Miniature”

The availability of radioisotopes made laboratory testing possible, but it also enabled large-scale atomic irradiation experiments such as a forest irradiation project in Georgia that exposed 300 acres of forest to an air-shielded reaction (?) that produced radiation levels comparable to expected fallout following a nuclear catastrophe.  The purpose of that experiment was to determine the impact of radiation on forests.  The findings were that some tree species were more vulnerable to radiation than others.  This finding contributed to the hypothesis “that the greater number of species in an ecosystem, the better that system will be ‘adjusting to stress.’” (1) This is the familiar theory that greater biodiversity enhances resiliency of ecosystems against stressors such as climate change.  It remains a cornerstone of conservation science. 

These studies are also responsible for the knowledge that radiation—and many other toxic substances such as chemicals—bioaccumulate, first described publicly in 1955, according to Martin.  Many toxic substances persist in our bodies throughout our lifetime.  The longer we are exposed to them, the more dangerous they are to our health.  Women who were exposed to DDT before it was banned in 1972 still have higher levels of DDT in their bodies than women born after 1972.  Many toxic chemicals also bioaccumulate in food webs.  Top predators in the food web are more heavily burdened with poison than animals at the bottom of the food web because of biomagnification

Using pesticides to study impacts and recovery

The concept of destroying an ecosystem for the purpose of studying impacts and recovery from impacts was soon extended to using pesticides.  In a study funded by NSF in the 1960, herbicides were repeatedly applied to clear-cut plots in the White Mountain National Forest to compare the runoff from “disturbed” watershed with “undisturbed” control watersheds.  “They concluded that forest clear-cutting led to the leaching of nutrients from the soil, and ultimately, algal blooms in downstream waters.” (1) (Yet, 60 years later, spraying clear-cuts with herbicides is still the norm in the timber industry.) 

Destructive methods used by Daniel Simberloff

The first publication (3) in 1969 of Daniel Simberloff’s academic career was a report of his Ph.D. dissertation project under the direction of EO Wilson at Harvard University.  He tented and fumigated with methyl bromide 6 mangrove islands off the Eastern shore of Florida to kill all the insects.  His objective was to study how long it would take for insects to recolonize the islands.

Although Simberloff monitored the islands for only one year, he concluded, “The colonization curves plus static observations on untreated islands indicate strongly that a dynamic equilibrium number of species exists for any island.” (3)  This is an example of the generalized conclusions of ecological studies noted by Professor Martin:  “With ecosystem studies, ecologists claimed that fieldwork conducted in one place could be used to understand other distant and different places.  The Pacific Proving Grounds became a model for lakes in Wisconsin, rain forests in Panama, deserts in China…” (2) 

Some 60 years and thousands of ecological studies later, such generalizations are rarely considered credible.  To quote one of the academic scientists who advises me, “If you study a specific site, you know something about THAT site at THAT specific point in time.”  Nature is too dynamic to reach a sustainable equilibrium and its complexity cannot be accurately generalized.  The concept of a sustainable equilibrium ecosystem was rejected by scientists long ago.

Laura Martin says of Simberloff’s study, “Destruction thus became a method of studying ecosystems. As Eugene Odum put it: ‘ecologists need not feel bashful about attacking ecosystems so long as they observe the rules of good science.’” (1)

Methyl bromide used by Simberloff in his thesis project is known to deplete the ozone layer of the atmosphere that shields the Earth from harmful Ultraviolet light that causes skin cancer.  Its use was severely restricted by an international treaty in 1989.  However, it is still used in the US for agricultural crops as a soil sterilant that kills all living organisms in the soil. 

The federally mandated Material Safety Data Sheet for methyl bromide says it is acutely toxic to aquatic life at the highest danger rating (Category 1). 

Nearly 60 years after the publication of his Ph.D. study, Daniel Simberloff remains one of the most vocal advocates for the eradication of non-native plants and animals.  With few exceptions, those eradications require the use of pesticides.  Simberloff may not have known the damage that methyl bromide does in the environment at the time of his study, but surely he knows or should know now.  Yet, he is still committed to the eradication of non-native plants, projects that require the use of pesticides.

Many ecological studies and associated “restoration” projects adopt the same viewpoint that destruction is a justifiable method of studying and “restoring” ecosystems.  “Restoration” projects often begin by killing all non-native plants with herbicides before attempting to create a native landscape.   Rodenticides and insecticides are used to kill non-native animals with the understanding that many native animals will inevitably and unintentionally be killed.  The Endangered Species Act accommodates the by-kills of these projects by issuing permits for “incidental takes.”  The law and the scientific community make a distinction between killing individual animals and killing animals on a scale that threatens the survival of the species. 

Killing and destruction were established as legitimate scientific tools over 70 years ago.  Given what we know now about pesticides and radiation and at a time when habitats are being destroyed by human activities and climate change, is it time to question the legitimacy of habitat destruction as a scientific tool?

A Preview

Professor Martin is also the author of her recently published book, Wild by Design:  The Rise of Ecological Restoration.  I look forward to reading it.  Meanwhile, I hope Professor Martin’s papers about the destructive origins of ecological field studies are a preview of her book. 

Update: I have read and summarized Wild by Design in this article, published January 7, 2023.

Happy New Year! We hope 2023 will be a more peaceful year.

  1. Laura J. Martin, “The World in Miniature”: Ecological Research at the Pacific Proving Grounds and the Materialization of Ecosystems, 2016 (unpublished)
  2. Laura J. Martin, “Proving Grounds: Ecological Fieldwork in the Pacific and the Materialization of Ecosystems,” Environmental History 23 (2018): 567–592
  3. Daniel Simberloff, EO Wilson, “Experimental zoogeography of islands: the colonization of empty islands,” Ecology, 1969

Part III: Appealing to the City of Albany to save its eucalyptus forest

I am publishing my letter to the Albany City Council about the City’s plans to destroy most of the eucalyptus forest on Albany Hill.  I am publishing it in three segments because it is long.  The first segment explained why it is not necessary to destroy the forest.  The second segment explained the consequences of destroying the forest.  The third and final segment explains why it is unlikely that the forest can be replaced by native trees.

Now you have my version of the full story. If this is a place or an issue you care about, please consider writing a letter of your own to the City Council of the City of Albany.

Conservation Sense and Nonsense

Albany Hill. Source: Google Earth

December 5, 2022

Albany City Council
1000 San Pablo Ave.
Albany, CA 94706

Dear Albany City Council:

SEE Part I and Part II of Appealing to the City of Albany to save its eucalyptus forest.  Part III is the concluding segment:

The uncertain fate of monarchs on Albany Hill is a suitable introduction to my final issue.  The proposed plans for Albany Hill claim the destroyed eucalyptus forest will be replaced by new trees. I will explain why it is unlikely that the eucalyptus forest can be replaced by another forest. Plans for a newly planted forest are described in various ways, some of which seem contradictory:

  • “[Margot] Cunningham’s [Albany’s Natural Areas Coordinator] team is pursuing grants to cut down most of the blue gums and plant the city’s side of the hill with a mix of native species and more drought tolerant trees for monarchs to roost.” (1)
  • “WHEREAS, the City is investigating consultants to design a plan to remove eucalyptus in a way that retains and restores more fire-resilient native plant communities and minimizes soil disturbance and soil erosion.” (2)
  • “More droughty Eucalyptus species can be planted to preserve the butterfly habitat.” (3)
  • “This plan will include but is not limited to: plantings of other tall trees in areas of the hill where monarchs have traditionally clustered; survey of the existing native understory which will be allowed to grow after eucalyptus removal; and analysis and design of additional plants of Albany Hill-sourced native plants.” (4)

Somehow, this diverse, drought-tolerant, fire-resilient, tall, native (with droughty eucalyptus species?) forest is expected to survive without irrigation:  “If drought-tolerant tree species are planted as seedlings, in the fall with sufficient planting site preparation and adequate rain fall, minimal if any irrigation will be required.” (5)  When predicting the fate of the existing eucalyptus forest, the plans assume that the drought will continue.  When predicting the fate of a replacement forest, the plans assume that the drought will end. 

Most public land managers irrigate newly planted trees (whether native or non-native) for at least 3 years.  Established trees rarely require irrigation to survive because they have extensive root systems that have better access to moisture in the soil than newly planted trees without extensive root systems.  Tree species that are drought-tolerant when mature trees, require irrigation as they grow their root systems.  Replacing healthy trees that don’t require irrigation with new trees that require irrigation seems an unwise choice in the middle of an extreme drought. 

The City of Albany should have learned that lesson when they built Peggy Thomsen Pierce Street Park at the western foot of Albany Hill.  Only native trees were planted in that park.  They weren’t irrigated.  Five years after the park opened in 2017, most of the trees are dead (see below):

Peggy Thomsen Pierce Street Park, November 2022.  Conservation Sense and Nonsense

The City of Albany’s list of approved street trees is a valuable source of information about what tree species are capable of growing in Albany.  A tree species that cannot survive conditions for street trees is also unlikely to survive on the ridgeline of Albany Hill, where wind conditions are extreme and there is little moisture.  There are about 65 tree species approved for planting as street trees in Albany.  Five are native to California, but only three are native to the Bay Area.  Native big leaf maples are said to be “in decline.”  Buckeyes aren’t suitable street trees, but may be suitable for open space.  None of the listed native trees are suitable monarch habitat for a variety of reasons:  canopy too dense to provide sufficient sunshine; deciduous therefore bare in winter; short stature, etc. 

Historically, areas on Albany Hill that are now forested with eucalyptus were treeless because native trees are not adapted to the challenging climate conditions.  If the eucalyptus forest on Albany Hill is destroyed, Albany Hill is likely to be treeless again.  That is the horticultural reality of Albany Hill. 

In conclusion:

  • It is not necessary to destroy the eucalyptus forest on Albany Hill because it is not dead.
  • Destroying the eucalyptus forest on Albany Hill will increase fire hazards and safety hazards.
  • Destroying the eucalyptus forest will destroy habitat of monarch butterflies.
  • Plans to replace the eucalyptus forest with native trees are unrealistic.

Please consider reinstating the 2012 Albany Hill Creekside Master Plan.  It is still a good plan that will not do unnecessary damage to Albany Hill and its human and animal visitors.

cc: Albany Fire Chief
Albany Natural Areas Coordinator
Albany Urban Forester
Creekside Science

Update:  Shortly after I sent my letter to officials of the City of Albany about their plans to destroy most eucalyptus on Albany Hill, they revised their plans because of two updated reports that were done in November and December 2022.  Basically, they no longer plan to destroy most eucalyptus on Albany Hill for two main reasons:

  • Eucalyptus trees are the overwintering habitat of monarch butterflies. They cannot be replaced by native trees of short stature without the open canopy that filters sunlight but also provides a windbreak the monarchs need.
  • Epicormic sprouts on the eucalyptus trees indicate they are recovering from drought and are expected to survive and eventually replace their canopies.

These are the sources of information that corroborate my brief summary of the main reasons Albany is no longer planning to destroy most eucalyptus trees on Albany Hill:

They still intend to remove dead trees to reduce fuel loads, to which I have no objection.  Some dead eucalyptus may be replaced with more drought tolerant species of eucalyptus from Western Australia. 

To be clear, I don’t think my letter about their original plans for Albany Hill were influential in their revising their plans.  My letter is consistent with the advice they received from an ecologist with expertise in monarch butterflies and a consultant in fuels management.  Credit belongs to the preference of monarchs for eucalyptus and to eucalyptus for being indestructible.

April 2023

  1. Bay Nature:
  2. Resolution No. 2021-105.  A resolution of the Albany City Council, authorizing the appropriation of funds to the Albany Hill Eucalyptus Project in the amount of $100,000
  4. Staff Report to City Council regarding Albany Hill Eucalyptus Project, May 2, 2022

Part II: Appealing to the City of Albany to save its eucalyptus forest

I am publishing my letter to the Albany City Council about the City’s plans to destroy most of the eucalyptus forest on Albany Hill.  I am publishing it in three segments because it is long.  The first segment explained why it is not necessary to destroy the forest.  The second segment explains the consequences of destroying the forest.  The final segment will explain why it is unlikely that the forest can be replaced by native trees. 

Conservation Sense and Nonsense

Albany Hill. Source: Google Earth

December 5, 2022

Albany City Council
1000 San Pablo Ave
Albany, CA 94706

Dear Albany City Council:

SEE Part I:  Appealing to the City of Albany to save its eucalyptus forest.  Part II continues:

The premature destruction of the eucalyptus forest will have many negative consequences:

  • The loss of significant amounts of fog drop from the tall trees.
  • The creation of tons of wood debris that will contribute to fire hazards
  • The regrowth of the trees into unstable multi-stemmed trees with lower fire ladders
  • The loss of habitat for overwintering monarch butterflies

Harold Gilliam in Weather of the San Francisco Bay Area informs us that tall non-native trees in the East Bay produce significant amounts of water by condensing fog drip: “Eucalyptus and pine groves planted there long ago intercept large amounts of fog and cause a rainlike deposit of moisture. The fog drip during the summer months has been measured at a surprising 10 inches, an amount nearly half as great as the total rainfall…”  Average rainfall in the East Bay is 21 inches per year, so this fog precipitation adds nearly 50% to total precipitation.  

Foggy morning, Redwood Park. Conservation Sense and Nonsense

One of the planning documents for the tree removal project on Albany Hill speculates that there is less fog than in the past in the San Francisco Bay Area.  According to an article in the New York Times, many people disagree with that assumption.

By precipitating fog drip during the otherwise dry time of the year, tall non-native trees reduce fire danger during the fire season.  Moisture on the forest floor helps to retard ignition and slow the spread of fire.  This was observed recently on the west side of Albany Hill when an arsonist set the forest afire in June 2022:  “The Albany Hill fire, which was initially estimated around three acres with a slow rate of spread…”  The fire was quickly extinguished.

This is where the fire in June 2022 occurred on Pierce St.  Note resprouts of the burned trees in November 2022.  Conservation Sense and Nonsense

Fog drip from the eucalyptus overstory is also irrigating the forest understory of many native shrub species, predominantly toyon.  Historical records of Albany Hill tell us toyon was not there before eucalyptus was planted.  The top of the hill is the driest area because it does not benefit from run off compared to lower elevations of the hill.  The side of the hill facing the southwest is drier than northeast face of the hill because it is exposed to more sun and wind.  Historically, oaks grew only on the northeast side of the hill where they were sheltered from the wind and the soil was moister.  One of many questions about the new plans for Albany Hill that should be asked and answered is how the existing native understory can survive without fog drip and the wind shelter of the tall trees. 

The City of Albany’s application for a grant from the California Coastal Conservancy predicts this future for Albany Hill: “The project will create more fire-resilient and healthy ecosystems by allowing native plant communities to return after eucalyptus removal…”  In fact, the opposite outcome seems more likely.  Without the benefit of fog drop from the tall trees and shelter from the wind, the existing native understory is unlikely to survive.  The existing native understory did not exist on Albany Hill prior to the planting of eucalyptus. 

This map (see below) of tree removal plans for Albany Hill shows where approximately 400 trees will be removed at the top of the hill.  (The number of each tree planned for removal is listed on this map, some in sequences such as 1-25, indicating that 25 trees will be removed between the arrows on the map.)

Source:  Arborist Report, SBCA Tree Consulting

Returning to the question of fire hazards, what will happen to all that dead wood?  We get a preview of the answer to that question because the City of Albany recently destroyed between 14 and 20 eucalyptus trees (reports on the number of destroyed trees vary).  We can see what happened to some of the wood (see below):

Some of the destroyed trees are still lying on the ground (see below).  This tree has already resprouted.

Multiply that flammable wood debris by 400 to get a picture of the amount of wood debris the proposed project on Albany Hill will create.  The arborist’s report for the eucalyptus removal project makes this recommendation regarding wood debris:  “Logs and chips to remain – Cut trees, chip brush and allow mulch and logs to remain on the slope.”

We had a recent experience with the wood debris created by similar projects when UC Berkeley destroyed all non-native trees within 100 feet of the north side of Claremont Ave in fall 2020.  Huge piles of wood chips and logs were stacked along the road, which the grant application claimed would be disposed of by generating electricity in a biofuels plant.  No such biofuels plant exists and there are no plans to build it.  Here is a photo (see below) of one of the wood piles that remained along the road for about 9 months before being distributed elsewhere throughout the Berkeley hills:          

One of many piles of logs, Claremont Ave, November 2020. Photo by Doug Prose, courtesy Hills Conservation Network.

Bay Nature recently explained why we are unable to dispose of wood debris from the many fuels management projects being done in California. If you ever wondered why there are piles of wood chips in your parks or why the roads in the hills are lined with logs, this article explains. There aren’t enough lumber mills in California to keep up with all the logs or biofuel plants to keep up with the wood chips. Most of the trees killed by bark beetles or by wildfire can’t be salvaged because of the shortage of mills. The wood debris is the fuel for the next wildfire. Turning living trees into dead wood debris does not reduce fire hazards. 

In addition to reducing fire hazards, Albany’s new plans for the eucalyptus forest on Albany Hill are also intended to address safety concerns.  Based on the assumption that the eucalyptus trees will soon die, Albany wishes to reduce public safety hazards by pre-emptively taking trees down before they fall down.  As I’ve said before, the assumption that the trees will soon be dead is mistaken.  Furthermore, Albany does not intend to use herbicides on the tree stumps to prevent resprouts, which guarantees that they will resprout, creating multi-stemmed trees that will be less stable than the trees are now. 

According to the arborist’s report for Albany Hill, there is also a history of unstable trees that grew from resprouts of destroyed trees:  Stump sprouts – Sixty-nine (69) trees have developed as stump sprouts, or trees that have grown back from the stump after being cut down. Because the prior tree stump eventually rots, the new growth is not always well anchored.” The staff report to the City Council on May 13, 2021 about the project said, “Multi-trunk trees are weaker structurally and produce more fire-hazardous debris than single-trunk trees.”

Trees develop their defenses against the wind as they grow in a particular environment.  When their tree neighbors are destroyed, they are suddenly subjected to more wind than they can withstand. The arborist employed by the City of Albany acknowledges the potential for increased risk of windthrow: “Stands of trees act together to resist wind forces.  When trees are removed from a stand or grove, the wind forces on the remaining trees are increased.  This can be a concern when trees, which are currently considered low risk, receive increased wind exposure due to adjacent tree removal.”

 The unstable multi-stemmed trees that grow from resprouts will also be subjected to more wind without the protection of other trees that have been destroyed.  The proposed plans for extensive tree removals will result in a more dangerous forest of resprouts that are vulnerable to windthrow. 

Destroying 400 eucalyptus trees on Albany Hill would create an overwhelming commitment to control resprouts mechanically. It is a challenge that the City of Albany has not been able to meet in the past, as evidenced by recent resprouts and multi-stemmed trees from past resprouts. However, I don’t mean to imply that I prefer the use of herbicides to prevent resprouts.  A new forest of young, unstable eucalyptus trees with lower fire ladders is better than a forest that has been poisoned and the understory with it.  Herbicides are also harmful to monarch butterflies and other insects.

My last visit to the City park at the top of Albany Hill was on Sunday, November 20th, the weekend before Thanksgiving, which is the optimal time to see monarch butterflies in their winter roost.  We saw many monarchs in the trees that are slated for destruction and as it got warmer in the early afternoon, we watched them flutter to nearby trees.  There were many other park visitors.  Some were frequent visitors who helped us find the biggest clusters.  Other visitors were as excited as we were to find the monarchs for the first time.  This is to say, the disappearance of monarchs on Albany Hill would be a disappointment to the visitors to the park.

Monarchs roosting in epicormic sprouts of eucalyptus on the top of Albany Hill, November 20, 2022.  Conservation Sense and Nonsense

According to Stuart Weiss of Creekside Science, that’s where monarchs begin their visit to Albany Hill:  “…monarchs begin the season on the ridgetop, likely attracted by high insolation [sunshine].  Following the first storms of the season accompanied by strong winds, they move down the SW slope when storm winds (generally southerly) are too strong.  The structure of the forest in the Cluster zone consists of a series of openings surrounded by denser forest, allowing some insolation with adequate wind shelter.  These cluster sites tend to have visible sky overhead with relatively few canopy openings toward the horizon and moderate exposure to the SW (which may be related to afternoon insolation.”

Stuart Weiss was also interviewed by Bay Nature about the monarch butterflies on Albany Hill:  “Weiss wants to preserve the eucalyptuses—invasive non-natives that they are—for the butterflies’ sake. The monarchs made their choice,’ says Weiss. ‘They go for the eucalyptus, so we have to honor that.’ The key to a cozy roost, according to Weiss, is a configuration of mature trees that provide just the right mix of sunshine and protection from wind and storms. Monarchs prefer to cluster along Albany Hill’s city-owned ridgetop early in the season. Later in winter, they cluster on the hill’s privately owned southwestern slope, and near the condos at the foot of the hill’s western flank. The fate of the trees and the butterflies roosting on that land is unclear.”

Eucalypts are the preferred trees for over-wintering monarchs in California according to an analytical study of 205 over-wintering sites:  “Three types of trees were used most frequently by roosting monarchs:  eucalyptus (75% of the habitats primarily Eucalyptus globulus), pine (20% of the habitats primarily Pinus radiata), and cypress (16% of the habitats Cupressus macrocarpa).  Twelve other tree species were identified…with a combined prevalence of only 10%…habitats had smaller populations when the roosting tree type was a species other than eucalyptus, pine, or cypress.”(1) (Three different studies by different authors are the source of these data, therefore they don’t add up to 100%.) In other words, virtually all of the trees used by monarchs for their winter roost are not native to the San Francisco Bay Area. 

The third and final segment of my letter to the Albany City Council will be published tomorrow. It will explain why the eucalyptus forest cannot be replaced by native trees. Thank you for your visit today.

Update:  Shortly after I sent my letter to officials of the City of Albany about their plans to destroy most eucalyptus on Albany Hill, they revised their plans because of two updated reports that were done in November and December 2022.  Basically, they no longer plan to destroy most eucalyptus on Albany Hill for two main reasons:

  • Eucalyptus trees are the overwintering habitat of monarch butterflies. They cannot be replaced by native trees of short stature without the open canopy that filters sunlight but also provides a windbreak the monarchs need.
  • Epicormic sprouts on the eucalyptus trees indicate they are recovering from drought and are expected to survive and eventually replace their canopies.

These are the sources of information that corroborate my brief summary of the main reasons Albany is no longer planning to destroy most eucalyptus trees on Albany Hill:

They still intend to remove dead trees to reduce fuel loads, to which I have no objection.  Some dead eucalyptus may be replaced with more drought tolerant species of eucalyptus from Western Australia. 

To be clear, I don’t think my letter about their original plans for Albany Hill were influential in their revising their plans.  My letter is consistent with the advice they received from an ecologist with expertise in monarch butterflies and a consultant in fuels management.  Credit belongs to the preference of monarchs for eucalyptus and to eucalyptus for being indestructible.

April 2023

  1. Dennis Frey and Andrew Schaffner, “Spatial and Temporal Pattern of Monarch Overwintering Abundance in Western North America,” in The Monarch Butterfly Biology and Conservation, Cornell University Press, 2004.