Tripvine

Transmutation
Level: Artificer * 1, Bard * 1, Druid * 1, Hunter * 1, Sorcerer */Wizard * 1
Components: V, S
Casting Time: 1 Standard Action
Range: touch
Target: 10-foot-long rope or vine
Duration: 10 minutes/level
Saving Throw: Reflex negates
Spell Resistance: no
  You animate a rope, vine, or similar Object so that it attempts to Trip any creature that comes near. The rope attacks anything in a 10-foot-square area you designate. The rope does not provoke an Attack of Opportunity. Its CMB is equal to your Caster Level +2. A tripped target that was running, jumping, or charging takes 1d6 points of nonlethal damage. Creatures aware of the tripvine gain a +4 bonus to their CMD against it.
  The Green Faith created this spell, but it is now common.