To zero in on your specific hunting spot, however, is simply a matter of reading the signs. For example, Pye notes, a good cold front that drops the temperature 4 or 5 degrees can often key the beginning of the rut, even though biologists believe that it's generally tied to the photoperiod, the length of daylight in a 24-hour period. Moon phase often plays a role in this.

But more concrete signs are available in the woods. "You start seeing and hearing bucks fighting," Pye said.

"At the peak of the rut," Longworth added, "a lot of bucks quit visiting their scrapes. They're staying with does, so they're not checking them as often. They may leave them alone for two or three days at a time."

Longworth also believes that does give out subtle hints that their estrous cycle is at hand. "When a doe comes in heat, she keeps her tail about halfway up in the air and twitches it," he said.

Pye too thinks that does also telegraph what's going on when you see them start consistently acting "spooky" -- checking their backtrails and hustling through the woods at a pretty good clip as if they're being chased. "You need to pay attention to every doe you see," he said. "Watch to see if they look in thickets and look on their backtrails. When you see does running from spot to spot, something is triggering that."

So if the calendar, the thermometer and the deer themselves start signaling that the peak of the rut is approaching, what's the best thing for a deer hunter to do?

Be there. Both Longworth and Pye say it's as simple as turning your wick up a few notches.

"This is when you need to spend as much time in the woods as possible, and it doesn't matter what time of day," Longworth said. "You'll start seeing bucks in the middle of the day, in the middle of the afternoon. You know they're covering a lot of ground, looking for does."

Pye believes that 65 to 70 percent of all hunters get out of the woods a couple of hours after daylight and don't return until the last two or three hours of the day. "The middle of the day is a good time to catch a big buck out; it's a fantastic time to set up or scout and look for them," he said. "There's less hunting pressure during the middle of the day.

"Most of the outfitters I've worked for and they guides I've known, they put their hunters out at daylight, and they ride and scout during the middle of the day. He's running does day and night, chasing 'em during the day. You've got to stay in your stand as long as you can to catch him out there. Take a sandwich and a piece of fruit and a drink and stay all day long."

According to Longworth, it won't help you to hunt the buck sign that you were depending on earlier in the fall, at the beginning of archery season. That's because the bucks are unlikely to be in that area and using those same trails -- not anymore: They'll be hanging out around does.

"You can throw away all the scouting you've done, because a lot of the time, the buck that made the rubs and scrapes you've found -- unless they're super-hot, and fresh -- could be a mile or a mile and a half away," Longworth observed. "And other bucks will show up that you don't see before the rut."

Those scrapes and rubs, Pye explained, are just a buck's way of marking his territory with warnings to other bucks, and invitations to does, before the rut really arrives. "He's spent the whole fall laying down his groundwork, his rubs and scrapes, checking food plots," he said. "He checks each doe individually. That's why food plots are good to hunt around, especially in the middle of the day.