How, honestly, is this spell more overpowered than Web (which is a 2nd level spell), connsidering this is a 5th?
Web is almost impossible to get out of if you miss your saving throw (unless you have a flame source and want to take damage, FoM, or any of the other spells to disrupt this one). A wizard actually *can't* fly out of a web, and still has to make concentration checks. The time is just as long (10 min/level), it covers a huge area..
I don't see it being broken at all, especially since there are more classes that have more abilities to render the spell useless (Rangers can't just ignore web like they can this spell..).