On Thursday, May 6, 1993, at 1522 hours Pacific daylight time, a Piper PA25 260, N4749Y, crashed shortly after departing runway 31, Pixley Airport, Pixley, California. The pilot was beginning a visual flight rules aerial application practice flight. The airplane, operated by Earlimart Dusters, Inc., Earlimart, California, sustained substantial damage. The certificated commercial pilot, the sole occupant, sustained serious injuries. Visual meteorological conditions prevailed. The pilot reported in a telephone interview conducted on May 12, 1993, that he began a right downwind turn shortly after lifting off runway 31. During the turn, the right wing began to raise and he was unable to arrest it. The pilot lost control of the aircraft and crashed. He stated that the surface winds were from 310 degrees at about 10 knots and believes that he encountered a "dust devil." The pilot reiterated his telephone interview statement, including the right downwind turn, in the Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1/2. He also provided a flight path diagram; the diagram showed that he initiated a left turn onto the downwind leg. Photographs provided by Mr. Norm Wilkins, Federal Aviation Administration, Fresno [California] Flight Standards District Office, show that the pilot executed a left downwind turn. The pilot also indicated that the airplane did not experience any malfunctions or failures preceding the accident.