I checked the blue bin on the lawn to see if Demented Dog Walker had deposited any dog turds within. (The one time I caught her at work, she told me that the woman across the street had given her permission to leave her dogs' doings in the recyclables bin.) She had. I retrieved the baggie and put it in the bag with my own biodegradable garbage in the freezer, and then noticed that my shoe balanced funny. As well it might, because I had trodden dog shit and leaves into the house. Followed much washing of floors and mats, and working at the crevices of my sole with an ancient tooth brush and an old kitchen knife, both of which went into the garbage thereafter. Examining the ground ivy that covers my front yard, I observe several mounds of dog poo camouflaged among the green.
Blue bin is going back into the alleyway-- inconvenient, but DDW can't access it from there. Wish I had a cat so I could send it to poo in her yard, but I don't even know where she lives.