Dust Blooms. Can we put a price on the services that urban flowers provide?

Alexandra Regan Toland, Dust Bloom (Close up of achene seeds of the dandelion ), 2016

Alexandra Regan Toland, Dust Bloom (Dust sensor with sculptural prototype ), 2016

Every plant, no matter how humble and small, performs a series of services for us. Some are obvious: plants provide us with food, remedies and raw materials. Other services they offer tend to be overlooked. They help filter water and cool the air, they create buffers against natural disasters, prevent soil erosion, provide shelter for animals. They also perform all sort of ‘cultural services’ for us: they can act as an uplifting background for our sport activities, become tourism destinations or inspire art, mental well-being and spiritual experiences. All of us, human and non-human alike, benefit from the presence of plants around us.

The Economics of Ecosystems and Biodiversity (TEEB) focuses on “making nature’s values visible” to decision-makers. The aim of the initiative is to demonstrate the values of ecosystems and biodiversity in economic terms but also to lay bare the costs of political inaction.

What might sounds like a cold and utilitarian approach is actually an invaluable concept that could spur us into appreciating, valuing and protecting plants and the ecosystems they are part of.

Artist and landscape planner Alexandra Toland worked with experts in environmental microbiology, urban soils, and of course urban ecosystem services to explore the ability of flowers to help filter atmospheric particulate matter (PM.) These ‘dusts’ can come from natural sources such as pollen but also from industrial and vehicular emissions and tire abrasion. Their presence in the environment has been linked to cardiovascular, respiratory and other health problems, especially in cities where there is relatively more pollution and less vegetation to filter it.

The filtering capacity of flowers is a neglected area of research, compared to leaves. However, the complex, three-dimensional structures of flowers make them valuable allies when it comes to regulating air quality by removing pollutants from the atmosphere. Toland’s project Dust Blooms juxtaposes the beauty and function of urban flora using a synthesis of artistic and scientific methods to create awareness about the every-day importance of ecosystem services in cities.

Dust Blooms started as field work, with the artist collecting the dust from wild flowers growing at the edges of heavily trafficked streets in Berlin. She then analyzed the samples to determine the type and amount of dust particles that covered the surface of petals.

The next step of her work consisted in visualizing her research. First, through botanical engravings that “graft” together elements of historical botanical illustrations from over 30 authors. These engravings were made from the very street dust collected on site. She also used all sort of everyday consumer goods (plastic dental brush sticks, microfiber wipes, polycarbonate screws, plastic clay, glitter, and granular resins) to create small sculptures based on the micro-morphological features of the Dandelion family. The synthetic plants are displayed “as glorified bricolage of the Anthropocene” on a flower bed while actual atmospheric dust levels are measured with Arduino-powered instruments.

Dust Blooms received an honorary mention at Ars Electronica this year. I got a chance to talk to Alexandra Regan Toland while she was busy preparing her show in Linz, editing a book about the challenges and creative possibilities of soil protection in the age of the Anthropocene, and tending to her many duties as a beekeeper, vermicomposter, forager, forester, and mother.

Alexandra Regan Toland, Dust Bloom (Macroscopic image of dandelion anther with pollen grains and diesel soot), 2016

Hi Alexandra! While reading the webpage for the project, i was struck by this sentence: “Flowering plants provide a host of ecosystem services in cities, such as climate regulation, the source of nectar and pollen for insects, and the purification of air, water, and soil.” I had no idea that plants were also seen as service providers. Somehow i find it a bit sad to see how we need to instrumentalize nature in order to recognise its value. Could you tell us about the importance of these ‘ecosystem services’ in urban contexts? 

I agree with your critique of the Ecosystem Services (ESS) paradigm but I recognize that it can be an effective way of protecting nature compared with other environmental protection strategies, especially in cities where there isn’t much nature to begin with. In our quest to design and build more sustainable cities, there has been a lot of research on urban ESS as a way of establishing indicators and standards. I see it as my job as an artist to visualize the ideas behind ESS but also to point out obvious ironies and contradictions. For instance, the fate of many medicinal herbs growing along roadsides seems to complicate the neat categories of ESS. These medicinal plants could theoretically be used for healing teas and tonics (a health-providing “service”) but are so filthy you would never want to pick them in the first place. So, it is somewhat ironic that age-old healing herbs like Plantain, St. John’s Wort, Yarrow, and Dandelion end up being healthful after all because they minimize atmospheric dust by cleaning the air of tiny noxious particles with their leaves and petals and holding the soil together with their roots. And they’re pretty to look at, poking up between fields of weathered asphalt and concrete, so their presence has a positive psychological effect too.

Alexandra Regan Toland, Dust Bloom (Taraxacum officinale (Dandelion)), 2016

How important is it for a plant to be recognised as a ‘service provider’?

We all – humans and non-humans – have roles and identities in the cosmopolitan order of the city. A plant can be my service provider (as in the filtration service I emphasize in DUST BLOOMS), my neighbour (as in the trees that line my street), my friend (as in the potted plant on my desk), my enemy (as in the allergy-causing summer grasses down the street).

I guess I like to think of ESS as more of a form of community work than instrumentalization. If we choose to see and value urban flora for their civic services – for making the world a better place simply by being there doing their filtering/cooling/sheltering/healing thing – then we might do our service to them in return by protecting biodiversity and open green spaces in cities.

Maybe the ESS paradigm is simply a projection of our own social democratic expectations of civil society to provide basic needs – a world in which all members of society are encouraged and expected to participate in some small way for the well-being of the greater community. So, plants and soil and animals and insects provide services to us while we can and should provide services to them. I’m not entirely sure that ESS can provide the right rules on how those services can be fairly valued and implemented, particularly on the human side, but it is an interesting policy strategy to consider.

Alexandra Regan Toland, Dust Bloom, view of the exhibition Lasst Blumen Sprechen – Artificial Nature from 1960, at Museum Schloß Moyland, 2016

Alexandra Regan Toland, Dust Bloom, view of the exhibition Lasst Blumen Sprechen – Artificial Nature from 1960, at Museum Schloß Moyland, 2016

Alexandra Regan Toland, Dust Bloom, view of the exhibition Lasst Blumen Sprechen – Artificial Nature from 1960, at Museum Schloß Moyland, 2016

Could you tell us about the way plants are filtering atmospheric particulate matter (PM)? How do they perform this task? How much of a contribution can they really make to the purification of the air? Which types of PM do they manage to clean up effectively?

The easiest way to think about dust filtration by plants is to imagine millions of living combs and brushes lining the street. The air passes through layers of undulating biomass that captures everything from larger debris such as weathered bits of trash and dead leaves to tiny diesel particles in the PM fraction. The type and source of dust is pretty easy to recognize under a microscope: pollen and fungal spores are geometric; grains of sand are usually smooth and translucent; soot and tire abrasion detritus is opaque black and edgy looking. All of these particles can get caught in the surface features of trees, bushes, and low-growing herbaceous plants. If you look closely at these surfaces you will notice that some are smooth, but many are hairy, scaly, pocked, wrinkled, folded, furrowed, spiky, or sticky, and these features can be densely or widely packed. So, different plants filter in different ways with different levels of filtration effectivity. Depending on the height, habitus, size and surface morphology of leaves and flowering parts, as well as the distance from the pollution source and pollution intensity, AND the position of neighboring buildings, which can act like canyons or wind tunnels, there can be very different filtering scenarios going on. The time of year is also important to consider, as trees in northern cities lose their leaves in winter. This is incidentally the time of highest levels of atmospheric dust. So, there is unfortunately no straight answer to the “how much” question, but it does make sense to plant as many trees and bushes along busy roads and to allow knee-high wild undergrowth to develop as a buffer between streets and sidewalks, where the pollution from exhaust is actually being churned out.

Alexandra Regan Toland, Dust Bloom (Hypericum perforatum (St. Johns Wort)), 2016

Beyond its artistic qualities, Dust Bloom seems to have made a valuable contribution to the knowledge related to the function of urban flora. How did you divide or distribute art and science in your project? Was the research process conducted strictly following scientific protocols?

I learned about the role of plants as atmospheric filters from colleagues in my PhD research program at the TU-Berlin‘s Institute of Ecology back in 2010. I was fascinated by the idea of living dust filters and knew I wanted to collaborate with the lead researcher, Ina Säumel, at some point on an art-science project. When Museum Schloß Moyland invited me to make a new series of botanical sculptures for a show on artificial nature they were preparing, I decided to explore concepts of plant morphology through sculpture and approached Ina with the idea of flower filtration, because up to that point no one had studied the filtration potential of flowers.

I didn’t really divide the “science” and “art” parts of the project because I saw it as an opportunity to delve into the phenomenon using several different methods: sculptural prototyping; historical analysis presented as a series of engravings; microscopic analysis of flower morphology and dust types; cartographic analysis and site survey; direct measurement using Arduino-powered dust sensors; and photographic documentation of different scales of observation.

All parts of the project were trial and error. There were scientific protocols for microscopic analysis, artistic protocols for mixing engraving pigments, and programming protocols for the dust filter. But there were a lot of “mistakes” that led to new discoveries and new questions as well. For example, according to the protocol we developed for the measuring campaign, we weren’t supposed to collect flowers within 72 hours of a rainstorm. In the end, as we were pressed for time and still hadn’t found any flowering St. Johns Wort, we picked some specimens after a rain shower anyway, fully expecting that all the dust had washed away. We were surprised to discover that some particles were still there embedded in the tissue, leading to new questions about how plants physiologically and perhaps genetically change based on their exposure to dust… Then, in the studio, I had been working with a much higher concentration of dust to medium, but after going away for a weekend I realized that the mixture would foul after a few days so ended up completely changing my pigment recipe. (The pigment is stable when it dries on the printed page.) In the end, knowledge creation, whether it’s relegated to the sciences or the arts, is a result of trial and error and methodological triangulation, meaning as social scientist W.L Neuman says, “we take multiple measures of the same phenomena and build on the principle that we learn more by observing from multiple perspectives than by looking from only a single perspective”.

Alexandra Regan Toland, Dust Bloom (Macroscopic image of dandelion pappus), 2016

The honorary mention at ars electronica is a sign that the artistic community responds with enthusiasm to your work but did you receive some feedback, opinions and remarks from the scientific community as well?

Other than a few presentations at the University, we haven’t published any papers for scientific journals yet, but would like to do so. To be accepted as sound science, the methods and measuring procedures must be clear but there must also be enough data to conduct statistical analysis. By the time the exhibition was set up in June, we didn’t have enough data from our measuring campaign and decided to continue the campaign and just exhibit the field and lab protocols so people could follow the process. We presented a research log with the one full data set we did have (dandelion), and detailed “character profiles” for each species. The field data from the dust filters was also incomplete, so we just showed how it worked in the museum. So, the project is most definitely still a work in progress.

In general, though, the resonance from the environmental science community has been very positive and encouraging. I think a lot of scientists are willing to work with artists, it’s just tricky to find funding and figure out ways of integrating artists into already running teaching and research programs. Also, the time and space constraints of an exhibition can limit the kind of work that can be done. It’s important that if a project identifies as art-science it has to work as both. Showing the methods and shortcomings and open questions of any research project is good practice. But those things can easily get obscured by the aesthetics of exhibitions.

Alexandra Regan Toland, Dust Bloom (Roadside dandelions), 2016

Alexandra Regan Toland, Dust Bloom (Sculptural prototypes), 2016

Alexandra Regan Toland, Dust Bloom (Sculptural prototypes), 2016

Why did you chose the dandelion as the hero of the project?

The dandelion is a special flower. There is something magical about the achenial seeds with their hairy pappus ‘wings,’ the milky, straw-like hollowness of the stem, and the curly bronze phyllary leaves at the base. The dandelion is a ‘model species,’ widely referenced in ecological research because of its highly adaptive morphological and genetic properties. Dandelions can adjust their size, shape, and metabolic properties to better deal with stress factors such as being grazed in rural locations, or dealing with pollution in urban ones. Its super adaptability makes the dandelion a so-called “super-species” – a complex group of species so closely related that, taxonomically, they are nearly impossible to tell apart. To model the dandelion is to honor 30 million years of subtle shape shifting through sculptural research. For me, the dandelion is also a symbol of graceful diaspora, which I think is comforting for many people around the world, including myself, who find themselves for better or for worse far away from “home.” The idea that the dandelion can spread wide and far and physically adapt to its new settings is inspiring and poignant. I collected the first flower samples with my daughter along the former East-West border in Berlin. Only a generation ago these seeds might have been the only organisms to parachute across the Oberbaum Bridge, where today thousands of cars speed over without a second thought leaving trails of dust behind them.

The research process involved a measuring campaign to examine dust from the flowers of several species at several locations in Berlin. What did you learn during this stage of the research?

Together with urban ecology students at the Technical University of Berlin, under the direction of professors Gerd Wessolek, Ina Säumel, and myself, a measuring campaign was carried out to examine dust from surfaces of flowers at multiple locations in the city from April to June 2016. Based on existing dust filtration data from Ina’s previous work, historical relevance found in old medicinals, a site analysis and knowledge of blooming periods, and of course aesthetic interest, we narrowed down our selection to the following plants: Achillea millefolium (common yarrow), Artemisia vulgaris (mugwort), Chelidonium majus (greater calendine), Geranium robertianum (Red Robin), Hypericum perforatum (St. John’s Wort), Plantago major (broadleaf plantain), Taraxacum officinale (common dandelion). Ten flowers per species were picked from major roadways in Berlin with an average daily traffic rate of more than 50,000 motorized vehicles. Five petals were then examined from each flower. Using light microscopy, it was possible to quantitatively estimate the surface area of a flower and qualitatively describe the morphological characteristics of individual flowers, as well as determine the type and amount of dust particles captured on petal surfaces. Each step of the process was documented in a series of photographs and field and lab reports.

I think the most important thing we learned in this process was the limitations of our own human capacity for work. Ina and I are both moms, juggling work and family life. We didn’t have as many students as we were hoping to attract with the project, so the burden of measurement fell on two people who had their own busy schedules at the university. It was really difficult to locate all target species in the determined 50,000 plus areas at exactly the right distance from the road, and exactly right time of peak flowering. We were also weather dependent. We had to collect our specimens during days with no rainfall, get them to the lab before wilting in the summer heat, and then not damage the delicate petals in the process of arranging them under the microscope. In the end, we had enough materials to exhibit by June, but realized as the exhibition came around that the measuring campaign was far from over.

I was very intrigued by the ‘representation’ chapter of the work. Your botanical engravings depict the evolution of graphic representation of weedy species over 350 years. How has the representation evolved over the years? Is it a question of the techniques used to draw the plants or is it because the plants themselves have changed their aspect?

Lorraine Daston and Peter Galison wrote a wonderful book called Objectivity (2007, Zone Books) that follows the history of visual representation and the changing relationships between scientists and illustrators over the course of several centuries. They discuss how botanists have relied on the help of artists right up until the present. “As long as botanists insisted on figures that represented the characteristic form of a species or even genus, photographs and other mechanical images of individual plants in all their particularity would have little appeal. Truth-to-nature spoke louder in this case than mechanical objectivity” (p109). However, there is a great deal of difference in the representations of these “true types” over time.

The plants have stayed the same, while our interest in them, as well as our technical means of representation continues to change. While pictures in medicinal herbals once included roots and underground plant parts, which were of great value to physicians and apothecaries, later illustrative works practically excluded the representation of roots to focus on flowering and fruiting parts, as they were thought to be more essential to taxonomic systems from Linnaeus (1707-1778) onwards.

As European colonial explorers ‘discovered’ a seemingly infinite amount of new plant species, it was botanical artists such as Claude Aubriet (1665-1742) and Georg Dionysius Ehret (1708-1770), who were instrumental in establishing their economic value in finely illustrated identification manuals known as Flora – in the documentation of new cash crops in colonial contexts; for the scientific advancement of botanical theory; and for the growing interest in horticulture in the gardens of affluent patrons. Ironically, the chosen species for DUST BLOOMS have appeared as prized medicinal herbs in herbals such as William Woodville’s Medical Botany (1792-1793), as well as appearing as villainous weeds in Emil Korsmo’s Anatomy of Weeds (1954). What was once a benefit to the physician became over time a costly detriment to the agronomist. These changes in representational focus inspired me to do a mash-up of different historical periods. If you look closely, you can see the pixelated rendering of the bit-map needed to make the engraving plates, as well as the inclusion of little insects flying around with brushes and q-tips. So, the historical illusion is broken. In a way, the engravings are a kind of digital grafting, akin to the grafting of economically valuable fruit and nut trees, but for weeds, which are valuable in their own way in the ESS context.

Alexandra Regan Toland, Dust Bloom (installation view), 2016

How important was it for you to use “anthropocene’ materials in the artworks?

There is a lot of critique on the legitimacy of the “Anthropocene” – as a term, a field of research, a moment in time, a social order, and as an epistemology. I don’t want to get into that debate here, but I will say that it was important for me to reflect Anthropocene ideas, such as the ESS paradigm and the problem of air pollution, in the very materials I was using for the artworks. Early on I knew I wanted to use street dust as a pigment in some way. The chemical composition of the street dust is unique to our times and adds a contemporary layer to the historical engravings. The materials used in the botanical models are also sourced from the very world they seek to understand. Characteristic inventions of our present society, like plastic dental brush-sticks, microfiber cleaning wipes, polycarbonate screws, plastic clay, and aquarium tubing, are fused together as material bricolage of the Anthropocene. What in other contexts is used to clean, decorate, or hold things together can be repurposed to represent environmental phenomena. Imagine all the R&D that led to Swiffer wipes to keep our homes dust-free. Well, we can similarly imagine the evolutionary R&D that went into the morphology of flowering plants, and they are out there cleaning for free! There has been a lot of R&D in the fields of biomimicry and geomimicry, looking to natural patterns and processes for solutions to human problems. The classic example is George de Mestral’s invention of Velcro based on the hooked burrs of the Burdock plant. I was trying to echo that process in reverse, by using human inventions to model nature as it appears in a very humanly altered state.

Thanks Alex!

Related story: Eulogy for the weeds. An interview with Ellie Irons.