The Bernese Mountain Dog has a double coat, with a longer outer coat and a wooly undercoat. Berners shed a fair amount, even more so during shedding season, which occurs twice a year. Weekly brushing—daily during shedding season—will help to remove loose hair and keep the dog looking his best. Any tangles can be worked out with a slicker brush or metal comb. As with all breeds, the nails should be trimmed regularly, as overly long nails can cause the dog pain and structural problems.