uncommon plant ranger transmutation 

Cast [>>] somatic, verbal

Range 100 feet; Area all squares that contain plants in a 5-foot burst

Duration 1 minute

You cause plants in the area to entangle your foes, with the effects of entangle. A creature that critically fails the save takes 2d4 persistent bleed damage in addition to being immobilized.

Escaping your bramble doesn't end the bleed damage.

Heightened (+1) The bleed damage on a critical failure increases by 1d4.

Advanced Player’s Guide, page 235.