plant poison transmutation 

Traditions primal

Cast [>>>] material, somatic, verbal

Range 120 feet; Area all squares on the ground that contain plants in an 80-foot burst

Duration 1 minute

The plant life within the area begins to writhe and lash out against your enemies as you call upon nature to impede your foes. To your enemies, the area becomes difficult terrain, and areas that were naturally difficult terrain due to plants become greater difficult terrain as well as hazardous terrain, dealing 6 poison damage to an enemy each time it enters an affected square.

Heightened (+1) The poison damage of the hazardous terrain increases by 1.

Secrets of Magic, page 117.