empty hulks of abandoned brick mansions.
Detroit had been hollowed out as white flight sent those who could afford to out to the suburbs, which in turn sprouted their own suburbs even further out. The steady movement of prosperity outward mimicked the growth of fairy ring mushrooms, which fruit in an ever expanding ring, often leaving dead grass in their wake. (photo from Wikipedia) I imagined those empty lots in inner city Detroit being cleaned up and planted with corn, spurring an agricultural economy that would expand outward as the older suburbs too collapsed in the ever outward push of development into rural areas.
As it turns out, there is a movement of sorts to make this happen. Here's one article, found by searching the internet for "detroit agriculture". Tonight at 7pm, the Princeton Environmental Film Festival will feature the film Detropia, which tells the story of Detroit's past glories and possible future.