Towards revisioning and appreciating “ruderal” (abandoned) urban landscapes

This article addresses and elaborates the other side of the usual argument against “invasive plants” — which, rather like “illegal aliens” — tend to move about, depending on conditions.

Did you realize that what determines the seriousness of ecosystem destruction is not the number of people living on the land but the amount of land covered over by impermeable surfaces? This and other facts startle. I guarantee that this article will teach you how to see especially degraded urban landscapes in a brand new way, and will help you learn to ask new questions, for example: if this plant is present, what does it mean about the soil? Plants are indicators, not pests.

BTW: for every “invasive” plant mentioned, I googled to discover whether it was medicinal and/or edible. And yep, every single one of the extremely hardy, adaptable, low maintenance plants (“weeds”) focused on in this article can be harvested for human use.

Mugwort (Artemesia vulgaris) growing along a salted street in Watertown, Massachusetts.

Mugwort (Artemesia vulgaris) growing along a salted street in Watertown, Massachusetts.

The Flora of the Future

Celebrating the Botanical Diversity of Cities

April 17, 2014

by Peter Del Tredici, via ranprieur, via Rose


“. . . ruderal or abandoned landscapes . . . consist of post-industrial or post-residential vacant land, and infrastructure edges dominated by spontaneous vegetation, either native or introduced, on relatively poor and often compacted soils. They have extremely low maintenance requirements — so low in fact that they can be considered self-sustaining.

One important research question concerning ruderal landscapes is how much land in any given city does spontaneous vegetation occupy? With the help of my Harvard Graduate School of Design students using GIS technology, we calculated that roughly 9.5 percent of the surface area of Somerville, Massachusetts, (one of the most densely populated cities in the state) is dominated by spontaneous vegetation. This is land that no one maintains, and it exceeds the land area occupied by maintained parks.


Ecological Functionality
The plants that grow spontaneously in urban areas — whether native or non-native — are performing important ecological functions. Ecologists refer to these functions as environmental services and they include excess nutrient absorption in wetlands, heat reduction in paved areas, erosion control, soil and air pollution tolerance and remediation, food and habitat for wildlife, and food and medicine for people (even if we don’t use it). [12]


Pavement cracks are among the most distinctive niches in the urban environment. Wherever you have two types of paving material coming together, you have a seam, and the different materials expand differentially in response to summer and winter temperature to create a crack. We tend to think of pavement cracks as stressful habitats, but in fact, as the water sheets off the pavement, it flows right into the crack, making it a rich site in terms of its ability to accumulate moisture and nutrients. With oil from cars as a carbohydrate source available for decomposition by fungi and bacteria, cracks can develop significant microbial diversity.


. . . most people refer to spontaneous vegetation as “weeds” — a term with no biological meaning. “Weed” is simply a word used to describe a plant that a person does not like or does not want in the yard. It is a value judgment that reflects personal preferences. Remarkably, there seems to be no Latin word for an unwanted plant, and in many languages “bad plant” (e.g., mala hierba in Spanish) is the only available term.




This entry was posted in 2014, permaculture principles, Reality Ramp-Up, waking up, wild new ideas. Bookmark the permalink.

0 Responses to Towards revisioning and appreciating “ruderal” (abandoned) urban landscapes

  1. wren says:

    i tend to think that plant species show up where they need to – to remediate, heal, inspire, complement, etc – in order to help the local ecosystem & its constituents. susun weed calls these “camp plants”, the ones which follow human settlements for one reason or another. the fact that mugwort & wormwood follow us around i believe says something about their psychic benefits (sleep next to a pillow dried mugwort leaves & your nightly dream-life will be enhanced & we have all probably heard stories about wormwood’s famous effect on bohemian artists via the drink absinthe, which IS quite tasty.) in a culture in desperate need of remediation, help from our interconnected species-allies here on earth (plants, mushrooms, animals, ETC!) is so necessary! we can thank the plants & animals for helping to balance us, for being there in evolution alongside us to point out dis-ease & ways toward balance. in a culture rich with “the way things are” i thank plants like mugwort for showing up & balancing our “night life” & 3rd eye visioning toward richer, more insightful, creative perspectives.

  2. laurabruno says:

    Reblogged this on Laura Bruno's Blog and commented:
    This is a fascinating and mind-opening article for anyone dealing with “weeds.” I’ve reblogged Ann’s post, because I appreciate her comments, but the rest of the article requires a click thru. I will say that my research has led to the same conclusion about “invasives” having medicinal properties. Japanese Knotweed, for example, is almost as difficult to get rid of as Lyme Disease … and lo and behold, Japanese Knotweed tends to “invade” Lyme endemic areas. Its resveratrol offers one of the most helpful remedies for Lyme Disease — in part due to the biochemistry, but, I believe, also due to the tough character of the plant, which mimics Lyme’s ability to take hold and overwhelm.

    Of course, I type this after a morning spent observing out yard, hand removing all traces of garlic mustard and plucking the yellow dandelion flowers before they become thousands of dandelion seeds — and before I go dig up dandelions from my asparagus bed. I appreciate dandelions — in the wild section of the yard. Meanwhile, I’ve enjoyed the contemplative observation of various ecosystems in our yard, as the dandelion plucking forces me to look carefully at what’s growing where — and to ponder why. “Weeds” tell us a lot about soil conditions, and they help remedy imbalances. Nature also works in trades. I plant many flowers I do want in exchange for removing the dandelion heads before they go to seed. Watching this quasi-urban, quasi-industrial, quasi-suburban yard transform tickles me to no end. Last week, a yard helper noted that the scary looking “weeds” I meant to pull were peonies. Who knows what beauty lurks in unfamiliar forms and unusual locations?

  3. Cindy W. says:

    Hee! Two people taught me this concept – Stephanie Mills in a book and George W., who introduced me to the “waste spaces” and weeds in the City of Cincinnati, and who had a “weed museum” in front of our home here as his answer to two neighbors who called in complaints to the local building inspector – bearing potential $300 fines – that he did not cut our grass every time it was more than 6″ high, and who sprayed herbicides on their lawns (which led me to Google “Bloomington” and “permaculture,” and discover this blog 2 years ago!) Yes! we had lots of Heliopsis and small white aster (the Weed Museum had signs giving the Latin name and vernacular name – I’ve since taken signs down but always let G.’s weeds grow in his memory). Have also been pulling the garlic mustard, while knowing it does have a use …

Leave a Reply

Your email address will not be published. Required fields are marked *