I watched an interesting show on this yesterday. The guy, said there are 4 types of deer blow/snorts. Alarm/Distress is 2 or 3 blows followed by a wheezing sound as they run away. Alarm only, is 2 or 3 blows - when the doe feels something isn't right, but doesn't smell or see you. Just thinks something isn't right. The other 2 were social snorts (i missed the end).

The guys point was you can occasionally use the snorts to effectively locate and call deer, especially when driving deer to hunting partners. The snorts will sometimes push bucks from heavy cover, and also other deer will snort back instinctively. Wish I could remember the name of the show....i think it was OLN.