First thing Henry did when up on the branch was to cast his eyes wide and his perception along with it just in case he was not alone up so high. It was unlikely already as, if Orcs were in the trees as they had been to ambush their group a while earlier, they would either had shot them all up with arrows or would have alerted the Orcs up ahead in the group.
Sure enough, there were no Orcs in the trees but Henry did pick up nests of birds but he barely cared enough to pay attention to what type of birds they were. They weren't his concern. The Orcs were.
Looking down into the group, it was almost too easy to pick out the one with the strongest energy and part of that was because it was exuding it so intensely that Henry could see it like a field around it.