I know that some dogs are good ground-scenters, while others of the same breed can be better at air-scenting. I also know that foxes are good at both, but I was wondering what the score is with deer - essentially whether their physiology makes them better suited to air-scenting? What I'm really trying to work out is how long after you've walked across a piece of land they can smell that you've been there (ignoring any residual airborne scent). Does anyone here know the answer?