On August 21, 1998, at 0630 hours Pacific daylight time, a Bell 206B, N223HA, entangled a skid in an irrigation pipe on takeoff and rolled over about 15 miles southeast of Salinas, California. The helicopter was destroyed, and the airline transport rated pilot, the sole occupant, was not injured. The local area aerial application operation was conducted under 14 CFR Part 137. The flight originated at the Salinas airport at 0500, and had made multiple landings at a support truck for additional fuel and chemical loads. Visual meteorological conditions prevailed and no flight plan was filed. The pilot reported that he had set down at the truck to refuel and reload the helicopter for aerial application. He lifted off, but did not have enough altitude to clear an irrigation pipe in front of him. The skids became entangled with the pipe and the aircraft rolled over to the right and impacted the ground in a nose down attitude. The aircraft then rolled over on its top left side approximately 180 degrees from the takeoff heading. The pilot reported that he had not experienced any mechanical problems with the helicopter prior to the accident, but had just misjudged the clearance with the pipe.