bloodcreek is exactly right IMO. When I look at a peice of timber, the first thing I look for is some kind of edge. If its pretty much equally thick through out, you might have to do some pre-season footwork. Look for terrain difference, places where the deer can move about without being detected. Ditches, draws etc are all good places. Sometimes, its so thick a treestand is worse than being on the ground enabling you to see under the canopy. Ground blind hunting is about your only option there. One thing you really have to watch for though is bedding areas. A lot of times, in this type of cover, they bed pretty much anywhere. Especially if they're not being pushed.