Board Thread:Speculation House/@comment-23568765-20131009143506/@comment-22580009-20131010233446

That was my assumption. Since Pyrrha said weapons channel aura, hers was channelled through Crescent Rose to create rose petals when she attacked. You'll also notice in ep. 8 as she is flying towards the nevermore after Weiss launched her she fires Crescent Rose repeatedly and creates rose petals.