If you’re lucky enough, you’ve seen Aristolochia serpentaria in bloom. If you’re like me, you almost passed it by, walking through the early June foliage of a floodplain forest. But something caught the corner of your eye and you stopped, did a double-take, and went back a step or two. You bent down to part the goldenrod and geranium and found the little nondescript plant there on the ground, its curvy tubular flower hidden beneath its leaves, purple and blotchy and arching up from the base of the stem. And you got down on your hands and knees and put your nose in close and tried to catch the faint whiff of carrion, although you weren’t sure if that’s what you smelled if it was just the damp smell of springtime dirt.
And then, if you’re like me, you got up from the ground, moved a few steps further on, and continued to fill your bag with garlic mustard.
The reason I bring up Aristolochia in the middle of garlic mustard season is that lately I’ve been thinking about extinction. Aristolochia serpentaria (though if you want to get picky, it’s recently been moved to the genus Endodeca), also known as Virginia snakeroot, is listed as threatened in Michigan, where a few stray populations hang on in floodplains and rich forests in the southern tier of counties. Though it’s never abundant within its range, it’s a little more common further south and east of us and has been assigned a rating of G4, which means that from a global conservation standpoint it’s “apparently secure.” So to be completely objective, despite its protected status in Michigan and a handful of other states, Virginia snakeroot is probably fine. From a global perspective, it’s not going anywhere, at least for the time being. There are much more imperiled species that we are worried about, species whose tiny populations and restrictive ranges put them at legitimate risk of being quietly blinked out by any number of means today, tomorrow, or ten years from now.
The problem though, for Aristolochia and other quasi-imperiled species, is that extinction doesn’t happen all at once. It begins as a series of little micro-extinctions, localized extirpations that in themselves aren’t very significant. A spotted turtle that’s finally driven out of its wetland home by a spreading wave of loosestrife, a purple milkweed that can’t hang on for another year under the shade of an encroaching grove of honeysuckle. From a metapopulation perspective, these losses are usually negligible. Any of these individual losses doesn’t put a species at much greater risk of extinction, probability-wise. But extinction is sneaky, and these things add up. It’s no coincidence that aside from outright habitat destruction, invasive species are the leading cause of species extinction worldwide.
Recently, I was re-reading an article I first encountered several years ago called “Planet of Weeds” by the science writer David Quammen. You can find it in a Google search, but the gist of the article is not so much to lament the fact that we’re knee-deep in Earth’s sixth major mass extinction period, or that we humans are the cause, but it’s to imagine the kinds of biodiversity that might be left after we’re finished having our way. It’s a look at the long view, thousands of years down the road, when ecologists with pessimistic streaks predict that only the weediest of species will be left in a dramatically altered state of nature. Quammen’s focus is mainly on the animal kingdom, and he sees our future burgeoning with things like pigeons, coyotes, rats, cockroaches, crows, and feral dogs.
You could add garlic mustard to that list, along with phragmites and buckthorn and everything else we pull, spray, burn, and hack out of our natural areas. Virginia snakeroot, though, is not on that list, nor is the pipevine swallowtail, a brilliant blue-black butterfly that uses Aristolochia as a host plant and is, not coincidentally, listed as special concern in Michigan. No, the common thread in that list of species is that, according to Quammen, “they are scrappers, generalists, opportunists. They tend to thrive in human-dominated terrain because in crucial ways they resemble Homo sapiens: aggressive, versatile, prolific, and ready to travel.”
It’s not exactly a happy feeling, knowing what our future is likely to hold. It’s no comfort, either, that we humans are overwhelmingly the cause of the problem. It kind of makes you want to give up, to throw in the towel, to stay home for the next garlic mustard pull. At least that’s how I felt when I first read the article. But this time around, I noticed something different about this description of humans and our invasive brethren, especially about the adjectives used to describe our tendencies. The same words used to describe our weediness also describe the tenacity by which many of us combat the decline of biodiversity in our natural areas: scrappy, opportunistic, aggressive. And that’s reason to be hopeful, I think. It may be a small hope, but it’s hope nonetheless.
Every year about this time, many of us hit the woods of nearby parks and preserves and backyards, braving rainy mornings, poison ivy, and the onset of mosquito season. We pull garlic mustard fervently and fastidiously, by ourselves or alongside others who share our strange passion. We lug out garbage bags full of plants and report our haul to the Stewardship Network. We return home, tired, the smell of stale garlic lingering on our clothes and skin for days. Our efforts may not have saved a vestige population of Aristolochia, and we may not win every battle, but we’ll sure put up a fight. We’re scrappers, after all.
– Justin Heslinga
Justin is a Senior Staff Scientist and Botanist at Cardno JFNew, an ecological consulting and restoration firm in West Olive, MI. He holds a Masters Degree in Terrestrial Ecosystems from the University of Michigan and has extensive experience with natural resource management. Justin and his wife Michelle spent over a year in Tanzania, working to further health education and address local environmental concerns as members of the US Peace Corps.