Walking through the woods near Colby College, Judy Stone gestures rapidly, pointing out plants. Norway maple, bittersweet, honeysuckle, a type of rose. All invasive. We stop for a moment to examine the rose, spending time appreciating its sharp thorns, its capable defenses. She tells me that she often takes groups on walks around Colby, and when this rose was in bloom, people stopped to admire it, look at its flowers, smell it, and talk about how beautiful it is. She didn’t have the heart to tell them that it was an invasive plant. They, like most people, couldn’t see the problems the plant was causing in the forest. They couldn’t see how ugly the invasives made this forest, because they didn’t have any experience with what she termed “nice” forests. The problem is not the arrival of plants from somewhere else violating the purity of a native forest. The classificatory principle at work sorts plants not by origin, but rather, by behavior. The relevant distinction is between plants that behave well in an ecosystem, that is, those that leave space for a diversity of life forms, and plants that behave badly, dominating the landscape.
Stone is a professor and chair of the biology department at Colby College. Her work is in population genetics, evolutionary ecology, and plants. The forest we are walking in is in the oxbow of a river, and invasives have proliferated in the fertile soil. Stone tells me that despite this a few nice things remain. A few feet on, she shows me a small, delicate plant, one that I am quite sure I would not have observed without her guidance. The plant is a native one, one of the things that make Maine forests special. Seeing this plant, Stone observes, “mixed in with all the crap there are still some nice plants. Most people won’t see it. They think it’s green, it’s nice.” Like most people, I am not attuned enough to the qualities of good or ugly forests to know how to appreciate this one, to distinguish between the ugly rose and the attractive little green plant.
A little further on, however, she draws my attention to a vine tangling with a tree, creeping up the trunk to envelope the crown, and spreading luxuriantly across the ground. The plant is dense, and it transforms what is elsewhere an open forest floor into an impenetrable one. The vine is Asiatic bittersweet, or Celastrus orbiculatus. This, she tells me, is “a plant behaving badly.” Even I can see how this has radically transformed the quality of the forest. The bittersweet is wrapped around trees, completely covering them and the ground, producing dense mats of vegetation. I have a picture in my head of a Maine forest, and this is not it. Bittersweet is a plant that even people who don’t know much about ecology will recognize as problematic. While some non-native plants grow primarily in ecosystems that have been disrupted (whether by human activity like logging, deforestation, or development, or by other events like fires or storms), Stone finds bittersweet particularly worrisome because it will grow in undisturbed forest.
Stone points to Norway maples as another example of badly behaved plants, noting that “homeowners don’t like them. Even the most unobservant person will notice—this plant is annoying.” Not all non-native plants are annoying. Apple trees, for example, are non-native, but well-behaved. They reproduce on their own, but don’t dominate ecosystems.
The walk I take with Stone transforms my experience of forests and roadsides. On a run a few days later I find myself stopping frequently to inspect the roadsides. What had previously been undifferentiated greenery has become divided—beautiful plants and threatening invasives. As I stop, touching bittersweet leaves and smelling pine trees, I think of Natasha Myers’ recent call for a “planthropology,” for people to get more acquainted with plants, and to “document the affective ecologies taking shape between plants and people.” Stone is committed to plants and is deeply familiar with them. Walking with Stone, I realized that, although she is formally a plant biologist and ecologist, one of her unspoken projects is to create a particular kind of affective ecology between people and plants, one in which people learn to see both the beautiful and ugly plants around them.
Knowledge of and commitment to plants means making these distinctions and policing plant behavior, identifying and eliminating bad actors, where the crucial distinction between “well-behaved species” and “plants behaving badly.” Stone’s commitment drives her to what I’ll call planticide. One of her hobbies is killing invasive plants. It’s listed on her website, where she notes “In my spare time, I kill invasive plants. Mostly, I kill: garlic mustard, oriental bittersweet, common buckthorn, bush honeysuckle, Norway maple.” Stone is committed to getting rid of these bad actors. She’ll go to lots where there are invasive plants, take a sample and leave it in a bag with information on the doorstep of the property owner, asking for permission to eradicate it. She finds herself out in vacant lots, pulling out invasives, and as she does, people introduce themselves to her. The act of weeding and tending to a vacant lot is very unusual, and people respond with curiosity and engagement. Along the way, planticide becomes an opportunity for outreach, for instilling new ways of understanding and interacting with plants in people passing by, for producing new affective ecologies.
People who become sensitized to the presence of plants and become invested in the surrounding ecologies may log onto iMapInvasives, a tool for mapping invasive species, where they can learn about the locations of invasive species, and the tools that people have deployed in attempts to eradicate them.
Stone is teaching people to appreciate plants as actors in the world, beings that can be both useful and beautiful or harmful and ugly, and whose behavior may need policing. Knowledge of plants and understanding of them creates complex new responsibilities and projects of care.