SD It is important to explain first that the black
hole in the map is not just because of an emphasis on agriculture; it is also because the taxonomic system simply doesn’t work there. It doesn’t work there because the soil has been turned over, basically, and this destroys the system of horizons that is used for this form of classification. Then, of course, a lot of other things happen to the soil of cities: things are added, burned, dumped, and leaked, which have no known effect on the soil. We can specify the effect in terms of pollution, in specific ways, but in terms of the kind of soil that roads or cemeteries make, it is not known, and, it is still in formation. And if we don’t know what soil it makes, we don’t know how to classify it. So, it is a point at which the USDA taxonomy becomes less useful for classifying soil because it solely operates on morphological properties, and the force behind a morphological classification of soils is the consistency of history that forms the morphologies. Here, in the city, we have a total breakdown of this consistency and history, at the scales of time that it takes for soils for form, and so it becomes very difficult to classify a soil morphologically. What you end up with instead, are engineering taxonomies that specify if a soil is good, or not good, for a specific function, a subway, a road, etc. So, we don’t know what it is, we don’t know what will happen to it, it’s just classified in terms of certain properties related to use. Soil as standing reserve once again. Soil in the Future of the Anthropocene
ET The absence of temporal consistency is quite
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interesting for soil science, not least because it repeats, in a way, Stoppani’s argument in the Corso di geologia, which was basically that although humans have been around for a relatively small amount of time, geologically speaking at least, their impact is epistemologically consequential, or not negligible for science, and this initiates his argument for the introduction of the Anthropozoic as an epoch. So the question of adapting a morphological system to account for an intensive moment that challenges the previous historical consistency is quite important in the longer history of the Anthropocene.9 How do you work
with that in your research?
SD It means that, in the city, history is the orga-
nizing force of soil formation. So, the urban condition calls for a return to genetic classification in order to understand the relationship between the soils that we make and the cities that we build. For me, the moment at which you disconnect, in a taxonomy, the relationship between the history of a soil and its morphology you cease to be able to see these in their real relationship. In the Eighth Approximation, I am arguing that urban soils call for a return to genetic taxonomies. My thesis was the project to built this taxonomy and see what it would look like. The system starts with a series of questions.Fig. 6 The first question, the highest taxonomic level, is: what was deposited? This makes a statement that, in a city, all urban soils are the result of a process of deposition. So, in the highest level, we answer the question of the mode of deposition responsible for the material. There are five groups: first, citified, or soils which are the result of the deposition of a medium previously available for plant growth, basically stuff which we commonly would recognize as soil, and maybe use in our gardens; second, gentrified, or soils which are the result of the deposition of mineral soil or regolith, which basically has no organic matter, or what we think of as non-soil, like mined rock or asphalt; third, commodified, or soils which are the result of the deposition of materials previously subject to a process of manufacture, and this is a category in and of itself because we have to understand the cycle of commodities inherent in the mode of deposition, which means we have to see the cycle of our economy as producing materials that, as waste, are incorporated into the physical fabric of our cities, like garbage, dead bodies, incinerator ash, construction debris, etc.; fourth, mortified soils, in which the mode of deposition is removal. This happens when the side of a mountain is scalped, leaving whatever is there underneath to form a soil; and, finally beatified soils, which are those soils that are pronounced to be undisturbed. Those are the categories at the highest level, and then beneath that, for example, in the