No, the argument about Steve and the tree tying began the night of May 9th and went on for around 3 hours into May 10th. May 26 was another argument.
ETA: There are posts in this thread about the May 10th argument, probably just a few pages back, I'll see if I can find them.
Here:
http://www.websleuths.com/forums/showthread.php?t=217310&page=17
Thank you so much. You are so right then. It makes no sense, the way the tree tying was brought up now in the tape when the day before Travis was basically mocking her. First off, her reaction to what he says, "what was that?" was put on, the way she did through the whole conversation, since it seems the tree tying fantasy began with her and Travis was only bringing it up to please her. But, I see what you mean now that I know the Steve Burns argument was from the 9th.