A layer of black soot coated every surface. Making the city look dark, and dingy, and dull. And while those with money could afford the staff to clean the surfaces of their homes, inside and out. Cleaning trees, less easy.
Enter the London Plane. It's a hybrid of the oriental plane, and the American Sycamore, and it's unusual bark shedding is ideally suitable to coal burning cities. As each layer of bark sheds, it takes with it the built up soot and dirt. Leaving a clean underneath.
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