I am not sure if I am alone in my thinking, but should people who ride horses not pick up their poo! We make dog owners pick up their poo and fine them if they don't.
Horses poo is a lot bigger than dog poo. I cycle along a track in the morning and evidently a horse has gone down it and left a big massive poo in the middle of the path. I am being serious, the owner needs to clean it up. Imagine if I went through it on my bike, ewe.
The person on the horse needs to get off, get a pooper scooper out, shovel it in the bag, put it over the back the horse and then dispose of it, simple. If anyone has any ideas as to why we fine dog owners and not horse owners do let me know.