Oops. Sorry for being a dumbass. Or since this is a French town, a Dumas.
While not being a anthropological geologist, I believe the reason for the fertile soil of Black Bootie is due to the Savoyard creek. I believe the source was somewhere around Eastern Market, headed towards Grand Circus, then down Washington Blvd.
there is an old thread around here with old maps and contemporary accounts about the Savoyard.
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