I got another swarm call for a swarm that was on the deck of a house trailer. When I got there the man said that they had returned to the oak tree that was only about ten feet from the deck. He advised that this is the third time that they left the tree and landed on the deck in the last three days. Are they doing this because they are swarming without the queen, and then returning to the tree? There is a large split in the center of the tree, about five foot from the ground up. The split is about ten inches wide. I can many bees covering the split in the tree but there is a small split to the right of the big split where they are entering the center of the oak tree. I placed a swarm box on the deck where they have been swarming to to see if they will swarm again and enter the swarm box. If not I will try to vacuum as many bees as possible on Saturday and add them to a hive I have in my bee yard. Any suggestions on why these bees keep returning to the deck and back to the tree will be greatly appreciated.