The pilot stated that he had just completed spraying a field and was landing to the north with what he estimated to be a 12 mile per hour tailwind. As the airplane touched down on the main wheels with the tailwheel off the ground, the airplane began to veer to the left. The pilot attempted to correct the airplane back toward the runway, but it continued to veer left towards a berm. He added full power to attempt to abort the landing, but collided with a trailer near the departure end of the runway. At the time of the accident, the nearest weather reporting station, located about 8.5 nm to the south of the accident site reported wind from 180 degrees at 16 knots. The pilot reported that there were no preimpact mechanical malfunctions or failures of the airframe or engine that would have precluded normal flight. The pilot noted that the reloading and refueling equipment is located at the north end of the airstrip and they always land to the north and takeoff to the south to save time.