From Alien Invader to Home Defense

I’ve learned a lot in the past two months. Although what I’ve learned relates to terraforming alien worlds by turning them into Earth facsimiles, some is more relevant to this world and my garden.

I’ve always enjoyed gardening, but never been any sort of master gardener. I watched with pleasure as the ligularia popped up in different places in the yard after I first put it in, and was quite excited because the butterflies loved it.  This seemed a great candidate for taking on a terraforming mission to another world.  So did barberry, bamboo, the butterfly bush, and English ivy.  (Those of you who are gardeners are shuddering, but bear with me.) Those plants are all sufficiently aggressive to serve as the right kind of alien invaders, I figured.

But my rather…assertive…mind set was as far as I’d gotten with my theory of terraforming.  I’m not a biologist, just a gardener.  I knew, however, that I needed a theory, particularly for my Martha’s Sons series, where stranded colonists are trying to survive on a world that isn’t quite right for them.  They’ve done what they can in terraforming one valley, but as some of them try to settle elsewhere, they’ve got a hard row to hoe.  I had been figuring that whatever propagated successfully in my yard would be useful off-Earth.  How wrong I was.

When I got an email from Izel Plants about a landscaping symposium featuring Douglas Tallamy, I got the germ of an idea.  Professor Tallamy’s topic was something that might lead me to a good terraforming theory.  Tallamy was going to talk about an interconnected ecosystem, biodiversity, and other large words that meant little to me at the time:

Recent headlines about global insect declines and three billion fewer birds in North America are a bleak reality check about how ineffective our current landscape designs have been at sustaining the plants and animals that sustain us.  Such losses are not an option if we wish to continue our current standard of living on Planet Earth.

The good news is that none of this is inevitable. Tallamy will discuss simple steps from his recent book “Nature’s Best Hope” that each of us can- and must- take to reverse declining biodiversity and will explain why we, ourselves, are nature’s best hope.

So off I went to take a look at his book instead, because I’m cheap and didn’t want to pay $45.00 for the all-day, on-line symposium. His newest book was sold out, but I picked up Bringing Nature Home.  I figured it was $20.00, which was cheaper than the symposium, and I’d have it to refer to later for more detailed information. Also, I’d save $25.00.

I finished reading, bought the next book, started making lists of which plants in my garden were natives and which were pernicious alien invaders to be repelled at the border with flood, famine, backhoes and boiling oil (but not pesticides), and otherwise became as enthusiastic as only a gardener in February can be–a gardener who is safely inside with the ground frozen too hard to require any digging at all.    Oh, and I signed up for the symposium, where he was the keynote speaker–because, what’s money?

But the book, you say.  What did he say in the book that got you so excited?  Well, two things, and they’re the same thing.  He did indeed provide a theory of terraforming for my personal alien invasion plans, but he also added me to the home defense team in terms of what I should be doing in my own garden.

Tallamy, who is a professor of entomology, makes the point that insects, including caterpillars and butterflies, are specialists, thus agreeing with Robert Heinlein who made the same point, so that makes him credible right there. Ninety percent of insects, including caterpillars and butterflies are super picky eaters.  They eat only one or two plants. With all the alien plants we put in our gardens, not to mention invasive aliens bequeathed to us by bird droppings, we deprive insects of food. This in turn deprives birds of the insects they eat, squirrels of nuts, etc, breaking links in the food chain right and left.

Terraforming alien worlds. For any wannabe terraformers, Tallamy’s observations suggest that we can’t just dump a bunch of plants–some from Brazil, others from Asia, a couple from Ohio–on alien planets. There’s a whole interconnected jigsaw puzzle to export if we want the new system to hold together, sustain itself, and thrive. I now foresee Terraformers, Inc. doing a survey of an alien rock world, seeding it with oxygen-producing cyanobacteria, waiting an eon, and then deciding which Earth ecosystem it’s going to install at what latitudes.  Terraformers would, perhaps, install a specific Mid-Atlantic (North America, Eastern Seaboard) Suite.  Or something from the American Southwest for Tatooine.

Terraformers would not assume–as I did–that sending plants that were aggressive, assertive, or invasive in my yard would be good prospects. (I have some fixing to do in Martha’s Sons.)  The intrepid settlers of distant worlds would have to be more careful than that.  If they chose the Mid-Atlantic package, for example, they’d take plenty of acorns because a white oak feeds (aka “supports” in the lingo) over 500 species.  That’s a lot of caterpillars for feeding baby birds or turning into butterflies.  And Terraformers would send plants that the creatures evolved with, because those are the ones the little dummies know to eat.

Gardening Here on Earth.  As a gardener, I’m not going to pull out my Korean boxwood or cut down the Chinese cherry tree, but I am going to start planting more native plants. In addition to the white oak, the willow and American cherry support over 400 butterfly and moth species.  Violets, golden groundsel, spicebush, and serviceberry feed multitudes of pollinators.  I’m really glad about the mass of groundsel we planted a few years ago.  It looks great and feeds bees.

I will be digging up and sending alien invaders to the landfill.  Yes, I said it.  Organic matter can go to the landfill.

I’ve already had my first weird experience in this regard.  Usually, when I dig stuff up I compost it or send it off in the county recycling bin. I feel all virtuous and like I’m contributing to the circle of life, feeding microbes, and making compost–aka black gold.

The other day I dug up about a dozen invasive Italian lords-and-ladies that had started appearing in my yard from nowhere. They’re attractive plants and were doing well in different spots.  They are not native, terribly invasive, and clog river banks and streams. In short, they are beautiful but evil.  And I put them all in a plastic bag for the trash and landfill. I felt like I was a) saving the eastern seaboard of these United States, but also b) destroying the Lion King’s Circle of Life.

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