Dog shit in a plastic bag.
Dog shit in a plastic bag has the advantage of not sticking to your foot if you step in it, but it doesn’t wash away in the rain and it doesn’t biodegrade. I honestly don’t get this – the dog owner has done the hard part, and then just left it there, as if carrying a sealed plastic bag a mere 30 metres to the nearest rubbish bin was way too much effort.
And now I am the crazy who photographs dog shit. Excellent.