Some common seed-dispersal systems. (Illustration: David Plunkert)

Certain aspects of spring make me squirm. Particularly those related to advice on what I should and should not plant. Even what I should actively eradicate. Insistent voices and ubiquitous manifestos inform me that I must limit myself to native plants—that is, those established before European and African settlement—and wage war on all others. Which you might think is mere hyperbole on my part, but that is not so. The desire to make my local environment resemble what it might have looked like before 1492, when Columbus crossed the ocean blue, is what drives the definition of “native” in a booklet just published by the Maryland Native Plant Society. Which makes me wonder why this document was not produced by a printing press, invented circa 1440, instead of some digital device available only recently.

On the surface, I have at least two problems with people who espouse this sort of nativism. First, I am not convinced that they love nature nearly as much as they claim. If they did, they would readily embrace an essential aspect: constant change. Which is particularly important these days since phenomena such as global warming are rapidly accelerating the rate of this change. Meaning that trying to make current vegetation resemble that of previous centuries, where the natural and man-made environment was decidedly different, is maladaptive, at best. If they must mess with Mother Nature, they might better ask what her future needs were and attempt to meet them. Second, they do not seem to understand the inherent futility of their efforts. Both plants and animals, including the human kind, are set up to spread. The salient difference between flora and fauna is that the former relocate by more subtle means. Say, through seed dispersal. And between autochory—most notably the use of gravity—and allochory—wind, water, animals and humans—them flora sure do get around. Of course, much of seed dissemination is polychorous, which makes those nativists that come down particularly hard on the human-vectored sort of dispersal come across as somewhat silly.

Deep down, there is another problem that I do not bring up with such nativists. Much like my father, who seemed to fear for his manhood each spring that my mother made him to lop off tree limbs and prune bushes, I—a non-native Marylander (here by way of Latvia, Austria, Germany, Michigan, Massachusetts and Alabama), a merely naturalized US citizen and a former displaced person—fear for my place in my present community, my adopted country and even the world as a whole at the start of each growing season. Because, invariably, I get sucked into discussions with those finding the likes of the multiflora roses and butterfly bushes on my riverbank offensive and then wonder just how they find me. You see, there is a political form of nativism that seeks to preserve or reinstate status for established inhabitants against the claims of newcomers and seems disturbingly similar to that of those seeking to reinstate some prior status of the riverbank.

The arguments used are certainly similar. And similarly questionable. They say, for instance, that the trouble with non-natives is that there are no natural predators to keep them in check. And that unchecked growth decreases biodiversity. Try telling that to our native beavers, who indiscriminately destroy the Japanese cherry trees, non-native but beloved, planted along the Tidal Basin and the native dogwood that I planted in memory of my mother. And to those humans, presumably native-born, who attack immigrants in our area and made life miserable for my family and five-year-old me when we arrived in Michigan. If diversity really is at issue, those nativists would beat on beavers, not butterfly bushes, which beavers blessedly leave alone. But they do not, any more than the other sort fights anti-immigration groups. Most would readily revert to 1965, when white people still comprised 85 percent of the population rather than rejoice that non-Hispanic whites will no no longer represent the majority by 2044.

Of course, nativists rarely seem to commit to reinstating the status of all plants or all people to anywhere near that of pre-colonial days. Few, for instance, show any interest in pushing for legislation restoring the status of Indian tribes. Even those who refer to them as “Native Americans” and admire their artifacts. And while dandelions are anointed by the Maryland Biodiversity Project and touted by the University of Maryland as nutrient-rich plants used by said Native Americans to treat a range of disorders, not many refrain from ripping those pretty but pesky natives from their lawns. Much like my mother in Michigan, who sought total annihilation as my father and and I stood by and smirked. (Monoculture lawns seem to be suburbanites’ sacred sites. When I worked in Washington, a colleague from posh Potomac said in all seriousness, “We have been invaded by violets.”)

Undogmatic by nature, I was pleased to learn that organizations such as the The Nature Conservancy now take a nuanced stance. Altering the orthodoxy that assumes that non-natives are guilty until proven innocent, points such as the following serve as rational replacements:

1. Non-natives can have devastating impacts, especially on islands,
2. But they can also provide much-needed habitats for endangered species and be the best bet for erosion and mudslide control.
3. Trade restrictions and border controls have reduced the flow of known pests, and some eradication programs have succeeded
4. But millions of federal dollars have been spent without any measurable impact on either biodiversity or ecosystem function.
5. It is important to protect against certain highly invasive species
6. But novel ecosystems are increasingly common and, going forward, will need to be viewed as part of the total ecosystem.

Not only are these points applicable to, say, my multiflora roses, which were, in fact, introduced to control erosion on riverbanks such as mine, but also to non-native humans such as me. Substitute some words in a Conservancy statement, and you will see. “Science-based conservation cannot be about knee-jerk platitudes and simple views of good and evil” any more than evidence-based immigration or refugee policy can be about knee-jerk platitudes and simple views .  .  .

The mixed blessings of introduced species are well-illustrated by the Columbian Exchange, that widespread transfer of not only people but also plants and animals and microbes, not to mention culture and science and technology, that took place between the American and Afro-Eurasian hemispheres as a consequence of the colonization and trade that followed from that somewhat ill-considered trip Columbus took. While non-native diseases certainly contributed to precipitous declines in indigenous populations, benefits accrued, as well. There was, for instance, no honey bee here back then. The same one that now is undergoing colony collapse and causing us to wring our hands about how we will feed ourselves in the future without this important pollinator. We probably will figure out a way, since humans—arguably the most invasive species of all—and ecosystems do eventually adapt.

Meanwhile, I will continue to root for those dastardly multiflora roses and butterfly bushes since those beleaguered bees sure do like feasting on their flowers. And that useless grassy hillside—it could barely be called a lawn—behind my house that I turned into some semblance of  a rain garden, full of non-native shrubs and small trees selected not only for their shade tolerance but also because they are not too tasty to our native white-tailed deer, who eat everything in sight. And those non-native lettuces and carrots that I plan to plant in our community garden. And the native tobacco plants, but only when they are restricted to the colonial garden, co-located with our own at the Benjamin Banneker Historical Park and Museum, which is dedicated to the first African-American man of science and son of a former slave.

I will also continue to support the Syrian refugees, not only because I was a refugee once myself but also because I cannot imagine how I would be able write another word without the elegant digital devices developed by a man whose biological father hailed from Homs. And the migrants who enter the country from the south, not only because part of the States once belonged to those below the border but also because one is my next-door neighbor. And to oppose those nativists who believe that closing borders and building walls will somehow “make America great again.” Not only because I cannot countenance their irrational hatred but also because they ignore their own history. Particularly the part where the Columbian Exchange and subsequent waves of immigration carried the seeds of greatness to their shores.