THE PILOT OF A PIPER PA-18 EXPERIENCED A GUST OF WIND FROM THE REAR SHORTLY AFTER LIFTOFF. THE PILOT LOST CONTROL AND THERE WAS INSUFFICCIENT ALTITUDE REMAINING FOR HIM TO RECOVER. THE PILOT MADE A LANDING INTO AN IRRIGATION DITCH OFF THE RIGHT SIDE OF THE RUNWAY. THE PILOT REPORTED NO MALFUNCTION WITH THE AIRCRAFT PRIOR TO THE ACCIDENT.