It's one of those thought provoking questions that inquiring minds want to know: Why do they roll in grass?

They are doing it for several reasons, mainly to leave their "scent" when they smell another animals "pee" or scent where they are rolling. They also do it to relieve an itch and this is their way to scratch. This one is way cool: Dog's love to disguise their scent with the environment, it's  camouflage to hide from predators and remain undetected by prey.