Druid roots (engulfing vs. engorging)

[Sonolin]

I'm currently in permafrost bear pits, and a couple people have mentioned it gets better when I get engorging roots at level 56. However, after looking into the wiki it looks like the only difference vs. engulfing roots is the amount of damage - duration seems to be the same. Is this some kind of urban legend or does the engorging roots actually last longer? Or does it get resisted less (although I don't really find engulfing to be resisted much in the pits)?

I'm curious if there's some mechanical reason to use higher level roots other than the listed max duration and/or damage.