“I hold no preference among flowers, so long as they are wild, free, spontaneous. (Bricks to all greenhouses! Black thumb and cutworm to the potted plant!”)
We live in concrete jungles, but the real wild things are growing in the cracks. Today’s urban landscapes do not resemble the wildernesses that preexisted them, but elements of wilderness are everywhere, creeping up brick walls, settling into vacant lots, rooting down, shooting up, and reasserting nature. Spontaneous urban vegetation is evidence of the world that goes on existing, even when we ignore it. Natural processes run through the built environment like water, channeled and deflected by the landscape we’ve made, and shaping it too.
The plants that live in city sidewalks tell us about the environment, what kind of place it is. A tree that would have flourished here a hundred years ago is now no more “natural” to this environment than a potted plant: the landscape has changed, and so has the ecosystem. Conversely, a nonnative species, or one that was once less common, may find itself well suited to life on the streets.
Such plants, which grow on their own, without cultivation or deliberation, are called volunteers. Cities are harsh habitats: fragmented, prone to disturbance, rapidly changing. Soil, water, and sunlight are not resources to be taken for granted. Environmental factors fluctuate wildly. Buildings, roads, and parking lots determine the flow of water through the ecosystem. Volunteer species are tough. Somehow, they are adapted to our habitat. Many originated in floodplains. Many have distinct reproductive strategies that give them an advantage in urban environments. They are able to get by in cities, however far they’ve come from their native habitats; they can cope with concrete, nestle into brick. They can thrive.
This series will be a tour of the urban ecosystem. We’ll visit vacant lots, climb chain-link fences, maybe fall into some roadside ditches. From the phytogeography of Baltimore’s abandoned blocks to coyotes in Chicago, we’ll examine the peculiar wilderness of cities.
Natasha Balwit is an undergraduate student in the Department of Urban Studies and Planning at MIT.