The pilot reported that he had landed in a field that had irrigation sprinkler pipes arranged in field rows. During takeoff and forward movement to reposition the helicopter, the right side spray boom caught on one of the sprinkler head risers which resulted in a dynamic rollover of the helicopter to the right. The helicopter came to rest on its right side and sustained substantial damage to the tail boom and damage to the main rotor blades. The pilot reported no preimpact mechanical malfunctions or failures that would have precluded normal operation of the helicopter.