 It can often tell, is it the grass outside? Is it the pesticides? What are you using outside in terms of fertilizers? What's going on out there? Or, for example, it could be inside where the dog rolls around more, so it would be more itchy on top and bottom, depending on the carpet cleaning or the regular floor cleaner that you're using. So there could be any number of reasons why the dog is licking their paws, although that all in one end of it,