In the scene where Julia Ormond and Aiden Quinn are on the hill at Tristin's grave, they are talking. One shot will show Julia's hair perfectly still, the next parted differently, the next her hair will blow forward, the next back, the next to the side, then nothing.
It wasn't Tristan's grave they were standing at, it was youngest brother Samuel's grave, the one Julia Ormond was originally engaged to when he was killed in the war. Tristan outlived pretty much everyone in the movie. Besides, wasn't it Brad Pitt (Tristan) that she was standing with, not Aiden Quinn (Alfred)?
You are right, it is Samuel's grave, but it is when Aiden Quinn asks her to marry him, that's when you can tell the cutting of different shots by her hair.
Actually, both are right. First it was Aidan Quinn standing beside her, and I believe that's the part Jenn is referring to. Later in the movie, Tristan comes home, and Julia Ormond finds him crying at Samuel's grave.
Due to no one being concurrent in this situation I am going to watch the movie just to see who was with her during the wind/hair thing. But again wind changes and as woman all do, we mess with our hair when this happens. So either side could be the part depending on how we adjusted our hair when messing with it after the wind took control. And both Triston and Alfred were both at the grave with her.