At a recent garden tour I saw some interesting lilies - they are taller than other lilies and have bulblets on their stems. A few are trumpet - like types while others look like asiatic lilies. I know that the tiger lily species are usually the one with the bulblets but are there other species that have bulblets. What names are assigned to those unusual lilies?

Someone said something about tree lilies and orienpets? I thought orienpets are kind of tender in zone 4 since they are hybrids of the slightly fussy (depend on who you ask) oriental lily and the non zone 4 hardy trumpet.