7 Reasons Why I Critique the “Invasive Plant” Narrative

Speaking as an environmentalist

Oxeye Daisy (Leucanthemum vulgare), along roadside in Yamhill County, Oregon. Yes, Oxeye Daisies are considered "invasive" though not a threat to intact native habitat. Please don’t hate the daisies!

I've been getting new subscribers at a steady clip lately, so I want to explain why I often write critically about the war on "invasive plants." Much of my work here is excerpted from, or inspired by, the book I'm currently working on with Nikki Hill, which is tentatively entitled, "Don't Blame the Messengers: A critique of the 'invasive plant' narrative." (Paying subscribers will get excerpts from the book-in-progress, and a full electronic copy of the full draft when it's done.)

"What is perceived is largely preconceived."
—Ashley Montagu, from his 1952 book, Darwin, Competition & Cooperation

Before I get into the reasons, let me say what I mean by “the ‘invasive plant’ narrative.” A “narrative” is a cultural manifestation; it’s a story that provides a lens for viewing the world and interpreting our own observations of it. Narratives manufacture biases and thus shape what we believe to be true. All social or political narratives (and there are many!) are comprised of facts, misinformation (errors), disinformation (purposeful errors), and ideology (both trumpeted and unacknowledged). Each narrative has its own degree of fidelity to the facts on the ground, some more than others, but none is wholly accurate. Because we’re human.

(For more on the power and role of narrative in shaping our perceptions, see this, by Caitlin Johnstone.)

Anyone who's been paying any attention to environmental issues the last couple decades is familiar with the "invasive plant" narrative. To pull a quote from the book-in-progress:

The narrative claims that “invasive” plant species “outcompete” native species; that they “aggressively” and “ruthlessly” “encroach on,” “choke out,” “push out,” “bully,” and “displace” native plants and that they “take over” ecosystems, “degrading,” “disrupting” and “destroying” them, causing “ecological havoc.” Our response must be a declaration of “war” where we “push back,” “stem the influx,” and “turn back the tide” by “fighting,” “battling,” and “combating” them, in order to “wipe out,” “purge” and “eradicate” them. We’re given a picture of monsters we must kill in order to save helpless victims from being gobbled up.

There’s a lot to be critical about with this narrative and its repercussions. As an image to incite fear and enmity against supposed villains, it’s very effective. But as a way of understanding ecological interactions, it’s not so useful. As a starting point for making intelligent and respectful choices about how we interact with nature, I believe it’s dangerous.

Why?

Reason #1: I love plants

My love of plants goes as far back as I can remember. One of my first words, no joke, was “Coreopsis,” because it was one of my favorites in the flower garden. I planted my first vegetable garden when I was six years old. I am drawn to all things green (and also to those plants who lack chlorophyll) and am endlessly fascinated with their qualities. I don’t view plants as subjects over which we have dominion, but as fellow inhabitants of a miraculously beautiful world who have their own right to be here. As such, I abhor the needless killing of plants (and indeed of any living thing). As someone who has spent years involved in farming, I know we have to remove some plants to make room for others, but that’s not “needless.” The “invasive plant” narrative devalues the lives of certain species based on only one factor—geographical origin—and excludes any other pertinent factors, such as the actual—not assumed!—relationship of that plant with its neighbors, or the history that led to its establishment. The result is needless killing.

Reason #2: I'm an environmentalist so I oppose pesticide use

I became interested in the topic because I oppose the use of pesticides. I was an organic farmer for about a decade in the Pacific Northwest (with Nikki for a big chunk of it). I believe we should cease the use of all herbicides, insecticides, fungicides, rodenticides, etc. And what's the most common method of eradicating "invasive" plants? Herbicides, usually by spray and sometimes by direct injection. The death or injury of "non-target" species (plant, animal and otherwise) is virtually inevitable when applying such substances, especially by spray. (Direct injection has risks too. Imazapyr injected into Tree of Heaven plants has killed neighboring native trees because the poison was exuded from the roots or traveled along micorrhyzal networks.) Pesticides remain in the environment afterwards, sometimes for years, causing all kinds of harm especially to aquatic life. Don't forget the humans who have to handle the stuff. So, I wanted to know if "invasive plants" were really such a big problem that they justify toxifying the planet even more than we already are. (Spoiler alert: no.) Non-chemical means, like mechanical and biocontrol methods, also have hazards in terms of collateral damage that should not be trivialized, especially as they are scaled up. Digging up some Himalayan Blackberry vines in a farm field is one thing. Brush-hogging acres at a time is another.

This issue of pesticides is non-negotiable for me. Further, in my opinion, anyone who advocates for pesticide use is anti-environment. I don't care what "conservation" group they work for. This is a hill I’m willing to die on.

Reason #3: The science is at odds with the narrative, and I think it’s important for people to know that

As I dug into the topic along with Nikki Hill, we found that the image trumpeted in the media and by various advocacy groups was not backed up by the science. There's a field of study called "invasion biology," with its own jargon, journals and conferences, which is, to quote one of its best known figures, "distinguished more by debate and controversy than consensus." (Mark Davis, "Invasion Biology," 2009.) As time has gone on, this has become more true. The researchers working in this field don't agree on a lot of things: how to define "invasive"; whether to use the term at all; how to quantify effects; how to categorize effects as positive, negative or neutral (yes, they identify positive effects too); how to distinguish apparent effects of introduced species from other factors like habitat disturbance; how to ascertain baselines; whether their approach is fundamentally biased and how to overcome that, and so on and on. Point being, invasion biology is not telling a simple story about bad guys, and less so all the time. To wit: The narrative is black and white. The science, nope.

Reason #4: “Invasive” plants are far more a consequence than a cause, so it’s a misdirection to make them the object of ire

One point of near unanimous agreement in the field of invasion biology is that "invasive" plants go hand in hand (hand in leaf?) with human disturbance (which is the single greatest threat to native species by the way). Unlike paratroopers dropping from planes or armies pouring over borders, introduced plants need an opening to establish, and that initial opening is made by human activity like farms, roads, clear-cuts, mines, dams, cities, etc. All these activities totally wipe out the pre-existing habitat, and make drastic changes to the soil, hydrology and other conditions, often making the place totally inhospitable to the previous residents, but quite welcoming to introduced plants. In any cases the new residents have been evolving to our particular disturbance styles for centuries or even millennia, and that’s why they’re at home there. Disturbance=invitation.

The presence of "invasive plants," then, is best understood as an ecological response. They are the botanical world doing what it always does, which is cover bare ground as quickly as possible and fill in gaps. They are nature working with what's at hand, and I personally marvel at the hubris of questioning nature’s judgment. It’s an entirely different subject whether we like particular plants or not, or whether they’re in the way of something we need to do, and we are free to weed our gardens as we see fit, but they are messengers not soldiers. Their presence—like the presence of every plant—tells us something about the conditions and the history of the place where they're growing. Spraying them or yanking them up willy-nilly won't do anything to address the underlying conditions that encouraged them to establish and then thrive. If restoration is the goal, it’s gonna take a lot more than plant removal (and it might not have to include that!). Restoration work must start with observation, study and reflection, not dogma.

Reason #5: There's much better ways to protect native plants

There is not a single case of a native plant being driven to extinction in the US by an "invasive" plant. Which is a fortunate because another point of near unanimous agreement in the invasion biology field is that "invasive" plants are here to stay. They have become far too established to be "eradicated" except in highly localized settings, and only then with vigilant, unceasing effort. Which might to be worth it in some cases. But overall we need to make our peace with a changed and changing world, and not pursue a fool's errand. This is not saying "hands off." We humans are "hands on" with plants and always will be, but we must be realistic about what's possible. Making these plants go away entirely ain't gonna happen. In the interest of preserving native plants and native habitat, we should put more of our energy into protecting what’s left. So: no lithium mines in the Great Basin, and no solar and wind farms in the Mojave, and no copper mining at Oak Flat.

Reason #6: We are harming ourselves by being hateful

I'm not a big fan of Nietzsche, but he was wise when he said: “Whoever fights monsters should see to it that in the process he does not become a monster." This is also why I oppose the "invasive plant" narrative. By embracing it, we validate some of our culture's more undesirable characteristics that need no encouragement: our xenophobia, our tendency to dichotomize, our obsession with idealized purity, and our view of the world as fallen from grace (à la the Garden of Eden). I also find it telling that the rise in the popularity of the "invasives" narrative since the late '90s has tracked with heightening vitriol against immigrants (especially since 9/11), and much of the same language is used in demonizing both. Who do we want to be, people? Let’s be careful what values we’re centering.

Reason #7: An adversarial relationship with nature is unhealthy for us and everyone else

But the label of "invasives" manufactures just that kind of relationship. We need to realign our lifeways to be place-based so that we can understand and work with the processes of change that are happening in the world right now, and every place is different, with no one prescription for all of them. Working with any locale will mean favoring some plants over others, as we have done throughout the history of our species since we starting using fire to manage landscapes, back before agriculture. These choices will be practical—and subjective!—and will be different in each location depending on circumstance, need, and resources. What is a dreaded plant in one place will be highly valued in another, as it has always been. Across-the-board rules like "this plant bad because not from here" are a hindrance to finding place-based truth and to seeking a respectful relationship with the planet as it responds to our abuses.

To sum up:

I love plants, pesticides are bad, the science doesn’t back up the hype, we’re targeting consequences not causes, protecting native plants is better done other ways, hate sucks, and war is not the answer.

Or even more to the point: I just don't believe the monster story.