The airplane contacted the ground and power lines following a loss of control during an aerial application flight. The pilot reported that prior to spraying, he circled the field four or five times waiting for traffic to clear on a nearby road. He stated he also dropped smoke to make sure the chemical would not drift toward the road. The pilot reported that during the last circle the airplane started to settle until it contacted the terrain. The airplane then bounced and contacted the power lines. The airplane settled back to the ground, and slid across a ditch and the road before coming to rest in a grove of trees. The pilot reported that the airplane most likely contacted a vortex which resulted from the circles he made around the field. In addition, the pilot reported that he did not dump the chemical load when the airplane first started to settle toward the ground.