Personally, I'm not a fan of roosting birds for the simple gamble of spooking them off the roost and ruining your morning hunt before it began. I like to do my scouting before the season and know days/weeks in advance where birds are roosting. Then I steer clear of the area until the morning of the hunt.

In an ideal setup, you could glass the birds from a distant and literally watch them fly up into a tree. IMO, it wouldn't hurt to bring a call and see if you can get a Tom to gobble...this will also let him know a hen is roosting near by which can play in your advantage. The main thing is to keep your distance, get to a high point where you can hear and see a long ways. But I would be careful, a wrong move and birds will spook and you will be left scratching your head in the morning. Good Luck