if they can tell how far away something is that they smell their reaction is different. like slip away in another direction or bolting. ya know what i mean? ever hear of a wind push. its using the wind to gently push deer. its not as crude/rough as a deer drive.
Ronn is right, Just because a deer does not blow at you does not mean he did not smell you. More than any hunter realizes deer just simply change their travel slightly to avoid you without any hunter being any wiser. This happens most of the time with the older wiser animals. On my properties there is one other guy that hunts there, I have killed 11 trophy bucks there non of which he even knew existed even though I had been patterning them for years. Think about it for a minute do you think for one moment this is by accident? He is retired and hunts 4-5 days a week compared to my once or twice. I can even tell if he or someone else has been there before me just in how the deer travel the property. Ronn has hunted there with me and knows I am being straight with you on this. Bottom line is play the wind, take every precaution with your scent control, and plan your entrance and exit to avoid at all costs to alerting deer you are or have been there. If you do these things I promise your deer sightings will go WAY up from what you have seen in the past. Do this and your trophy buck will just magically appear even though you never knew he lived there. I believe that most areas have a mature buck that uses them it is just he has done a better job of patterning you than you did of him.-------- My finger is tired now so I'm going hunting.