So Rowdy is very good about not chewing on inside furniture, clothes, etc, but when I take him outside he tries to eat EVERYTHING.  I know that puppies like to be oral, but this is a whole new level.  I am constantly pulling rocks, tanbark, sticks, plants out of his mouth.  When I catch him eating something he shouldn't I loudly yell "NO" once and pull him away from that.  He just won't stop eating dirt, rocks, wood, etc.  He even puked up a bunch of tanbark last night, despite me trying to not allow him to swallow them.  How can I stop this?  Anything I should be doing that I'm not?  I do not want to end up with stomach surgery on my new pup.