I was just reading the how deer see (something along those lines) thread and someone mentioned deer seeing horizontal movement. Well that reminded me of something my dad told me the first time I ever went deer hunting and it always stuck with me and I told my son the same on his first hunt.
Everything in the woods with few exceptions is aligned in a vertical manner. Except deer. Deer are aligned horizontally so learn to look at the woods and with respect to identifying horizontal lines. You can scan everything else, but when you see horizontal lines stop and investigate them until you know what they are. Chances are great it will be the line of a deer’s back or the line between the brown over the ribs and the white of the belly.
He also told me to understand the fact that you will rarely see the entire deer so once you’ve identified a horizontal line start looking for the round of the eyes, the white around the ears, the white line mentioned above and the white patches on the inner legs, face and neck. I can’t tell you how many thousands of time I’ve seen deer in my lifetime by following that advice. In fact, that was almost 50 years ago and the last hunt of this season, New Years Day, I say a horizontal line that turned into a bedded doe. I could only see about a 12-15” section of her back and nothing else, but I had convinced myself it was a deer. Then about 25-30 minutes later she stood up and erased any doubt.