“INVASIVE SPECIES”

Plants & Restoration: “Where is it at home?” vs. “Where is it from?”

Kollibri terre Sonnenblume
2 min readMar 15, 2022

In pursuit of an approach based less on ideology and more on real world dynamics

Fireweed, at observed in Mt. Hood National Forest in Oregon, 2013. Photo by the author.

In 1912, Albert Thellung (1881–1928), a Swiss botanist, was one in a long line of people who proposed a taxonomy to differentiate various types of native and non-native plants, and though his system never caught on, we’d like to call out one of his designations: epœkophytes. These are plants that, in his words, are

“present since recent times and also constantly reproducing, but restricted to artificial localities (e.g., especially liking fields and vineyards). The persistence of these species depends on man, who must preserve (or rather continuously re-create) conditions appropriate to them (plowed ground, cleared patches); they produce ripe seeds in sufficient quantity, but they cannot compete with invading indigenous species.”

Note the use of “invading” for a native species. Here, the word describes a habit of growth, and has nothing to do with geographical origin. Also note the hypothesis of a species that depends on continuous man-made disturbance, and that might go extinct without it. Which raises some questions. In the context of ecological restoration that aims to return ecosystems to their “natural” or “untouched” condition, where do plants like this belong?

The characteristic of “nativeness” has been in the forefront of so many environmental discussions in recent years that perhaps people are unaware that other attributes could additionally (or alternately) be used as a basis for an ecological viewpoint. Instead of the question, “Where is it from?” we could ask, “Where is it at home?” and consider habitat without regard to region. Possible answers could be, “logged forests,” “unpaved paths,” or “overgrazed pasture.” Matching plants for those three are, respectively, Fireweed (Chamerion angustifolium), Broad-leaf Plantain (Plantago major) and St. Johnswort (Hypericum perforatum). Broad-leaf Plantain is so at home in the compacted soil of paths that it was named “footprint” twice in history, first by the Romans with “plantago,” which is Latin for “footprint,” and then by Native Americans as “White Man’s Footprint,” because they noticed it growing wherever Europeans went.

In an interview we conducted with biologist Julie Stromberg, she asked rhetorically, “What’s native to a ditch?” In terms of geography, we suppose the answer is “nothing,” but in terms of ecological conditions, a long list of plants have spent millennia adapting to ditches, and while they are not “native” to them, they are certainly at home in them. We believe this should count for something in the interest of pursuing an approach based less on ideology and more on real world dynamics.

After all, are we really willing to make the claim that we know better than nature what “belongs” where?

This is an excerpt from a book-length writing project that Nikki Hill & I are working on.

--

--