[Aarone]

Leokaiser's correct, Ensnare/Ensnaring Roots are unreliable until you're a) consistently higher level than what you're pulling or b) are at least several levels higher than the spell's level (both are 29, correct)? You'll get a feel for when they will work, and when they won't.

As a general rule of thumb, kite reds/yellows and root rot blues, until you get the familiarity and feel for both, and then you should be able to intuit when you can modify your tactic situationally. Also (esp. if attempting reds), if the snare doesn't land right away (first couple of attempts) then get out of Dodge and try again later - the resists on the Snare are only indicators of likely resists on the rest of your casts.