Besides Dog crap there is also chewing gum.Instead of leaving it on the bedpost over night, chewers leave little scrumpled balls of it wherever you look. It then gets splatted flat into the ground by somebody's shoe.It takes 5 years to break down on its own apparently. Filth, utter filth.
I would like to chase after the culprits with their bit of gum and say 'Hey, yours I believe' and pat them on the back with it.Better still,ram it back into their gobs. Ban the bloody stuff, its no good to man or beast.