The dog may be scratching the ground because it is grinding its claws or to cover up the smell, because the dog’s nails will also grow. If they are not trimmed regularly, they will become longer and affect the dog’s walking, so the dog will grind his claws on his own. . Grinding your dog's claws can easily lead to paw injuries or damage to furniture, so it's best to trim your dog's nails regularly. It is also possible that the dog smells something after peeing on the ground and wants to cover it up.