What jumps/spooks more deer?

When walking to your stand?

Scent? If you are determined to hunt a particular stand even if the wind is not favorable for getting there undetected.

Sound?

They see you?

They see your light (early morning hunts)?

I've also wondered how many deer I've run off that I didn't see or hear. There is no way to know with certainly the answers to any of these, but what have you started doing differently to improve your hunting?

Sound. I've watched deer as my ride approached, and sound puts them on high alert. They'll run when they see headlights.

I've started walking slower to the stand and using a red light. I try to go in completely silent. That being said, I took my best deer this year when I was dropped off close to the stand on a gas powered sXs that was used to drive through the plot and pull memory cards from all the stands at lunch time, so who knows. But I feel like it helps my odds and thats all that matters.

I would say smell/sight/sound. Leave in time to slip to your stand quietly, downwind of where you expect to see deer. The approach should all be figured out before the day of the hunt.

I used to be in the "get in an hour before daylight" and "let things settle down" group. Then I realized how many deer I could hear running off due to me bumbling in the dark.

Now, I start my walk in at good seeing light. I've walked up on deer that would have seen me had I tried to get in earlier. If you take your time and slip in from downwind you won't need time "to let things settled down" because you never stirred things up. My two pennies.

And stay off those 4wheelers and use the 4wd the good Lord gave you, your two feet.

With the exception of the noise made by 4-wheelers…..I’d say scent plays a FAR larger role than any leaf crunching noise you may make walking to your stand. The farther you walk to your stand too….the more scent you’re laying down on the ground and on the bushes as your move through the woods….. as well as the more scent you cast out across the landscape downwind of where you’re walking. The conditions will dictate how far downwind your scent stream travels and how long the scent on the ground will linger.

I have stumbled in during the early morning hours, gotten all the way up in my climber and had deer walking underneath me five minutes later...despite all the noise I made walking in on crisp leaves.

On the contrary, we've all had them pick up our scent from over 100 yards away, give us a snort and never even see the darn deer.

Scent is by far the #1 deer deterrent. Their eyesight is not that good and it can be hard to distinguish the actual source based on sound alone. When a deer hears something, they'll usually look that direction to identify what is making the sounds.

Here's my justification for claiming scent to be the number one deterrent. Almost every hunter has a favorite stand or stand site. All of us have probably noticed that fewer and fewer deer are seen from our stands as the season wears on. We label that "pressure" but that pressure comes in the form of hunters leaving their scent behind many hours after they've gone. If the deer were not avoiding the human scent, we wouldn't continue to see fewer deer as the season wears on.

I quit going in before first light. I now walk to my stand regardless of distance at first light taking my time in doing so. They don't like 4-wheelers. I pretty much hunt the wind in my face when I'm on the ground or shooting house unless I'm jacked way up in a tree overlooking a cutover or large open area at which time I'm not worried about my scent. I wear clothing that is basic in color schemes (a lot of browns, black and dark greens), and washed with scent & UV killer detergent. I've had a lot more success hunting this way.

Agree with above post 100 %

we take electric golf carts in, always pitch black, and still walk a pretty good ways. Usually have cleared access path to stands to minimize sound. Always plan a slow, as quiet as possible entry based on wind and expected deer movement. I try not to use a light.

I agree with what MarksOutdoors said above, I often haven't gotten in good when I have deer coming by.

I really don't believe that they can tell the difference in a human and a raccoon/armadillo/anything if you are going slowly and as quietly as possible.

All that being said I think scent is biggest factor in spooking

Not only am not trying to spook deer on the way in, I don't wanna spook anything, I feel like the more critters moving around me the more comfortable the deer are. I like to watch when other animals are feeding, I watch the other animals and there activity just like other animals watch each other to see what's going on in the woods. Scent is the biggest obstacle. There's not a whole lot you can do about it, you can minimize it as much as possible, but it's still there. I do as much as possible to have the least impact on the woods though.

I would say scent by far. I've seen deer within minutes of turning off the four wheeler or other people driving by in vehicles/atvs. I can't count the deer that I've heard blow and never seen which was probably due to a scent issue.

I've had deer come straight at me. I even had one snort wheeze at me, only once though. But I've had 2 experiences like this I just didn't shoot... Watch the whole video. It comes in with nothing but sound on its mind.
https://m.youtube.com/watch?v=0joLRD3KbW0

I agree scent is number one.

I agree that scent is #1 if that's all you take into account but I believe that a lot of times deer don't spook when just one of their senses are triggered.

I know I have had deer see, smell, or hear me before and not move an eye lash until they were able to employ one of their other senses to determine what they were dealing with.

That being said, I really think that a combination of two of their senses is what jumps/spooks most deer.

Just my opinion.

Lot of other variables including pressure on surrounding land and existing pressure on your own land. Another is night hunting.

I slip in as its breaking light. On a heavy frost morning about an hour after daylight. Unless I'm hunting a cutover with a SE facing ridge. If you have time and plan on going in later, walk SLOW. Take two or three light steps and stop. Wait a few seconds. Listen. Walk a few steps. Stop for a minute. I've killed a few coming to check me out. I know it sounds stupid,but it can work. Figured it out hunting some steep hills on my Dad's place. Just kind of a hail marry thing I do every now and the late in the season. Works best if you walk below a ridge.