Pat,

they use a method called poussée silencieuse, which means they have trackers who just walk through the woods in a line, no noise, no dogs. The deer and pigs just stay in front of them.
This is a good way for deer but the wild boars tend to wait and hide until the trackers are too close. And then they shoot passed your treestand. In normal conditions you can take a shot but when your numb from the cold they have the advantage.
I have some friends/hunters who have rough haired teckels for tracking and a german terrier species they use to spike the boars with ( keep them in one spot ).
Only rifle hunts with the dogs, they don't trust bowhunters to take a shot when the dogs are around the pigs.