When does Bran need the Weirwood tree?

[Jack Bauer 24]

So when does Bran need the weirwood tree? He was there when he saw the vision of Sansa/Ramsay, Arya/Crossroads, NK taking down the Wall, but he was able to see the Rhaegar flashback sitting by the fireplace with Sam?

[Dornish Gourmand]

Good question. We know that he has the ability to warg and see other places presumably in real time without the help of the Weirwood tree. I had also assumed that he had to be connected to it to time travel/telepathically communicate with others.
Maybe he's learning to "see better" and doesn't require constant physical connection to the Weirwood any longer? Like a blood magic Bluetooth signal...

[evenwind]

I think the simple answer is "when B&B decide it". The have been many instances where logic has taken a back seat to the story and this seems to be another one.

[Stormborn]

Bran only needed the trees to see visions from the past when he first discovered this ability. I think this might have been explained by his predecessor in a season 6 episode. In this season, his abilities now include: warging into multiple creatures at a time (the crows/ravens flying to the wall) and stepping into visions at will. Sitting by the tree is probably just where he likes to be although they do have knowledge and magic in them.