I agree with mags. I have found that having more than one stalk is a pretty sure sign that the bulb has divided.
Yesterday I dug out an oriental "Summer's End" that for the last four years or so has put up four stalks. Sure enough there were four bulbs all stuck together. I wish I would have taken the time to photo some of the amazing stuff I found when digging out my lilies this fall (almost all of them).
Yeah, lily bulbs are awesome. I can't think of any other bulbous plant where I get almost as excited about the bulb as the bloom.
