Use all of your senses to find roost trees. Watch and listen hard at dawn and dusk. Gobbling and gossiping flock talk is the primary indicator of spring roost sites. Once you home in on areas of activity, find the specific tree that birds are roosting in, then set up within shotgun range in the dark. As turkeys start to stir, do not move. Do not call. If you do either, gobblers will focus on you, and seeing no hen, they'll pitch out the other side of the tree. But by getting tight to the tree, then shutting up, there's a good chance your gobbler will fly down within range.