The pilot reported that he took off on the aerial application flight with the intention of spraying a field. The pilot stated that he was 200 feet above the ground as he approached the field. The airplane lost airspeed and altitude as the pilot maneuvered to align his flight path with the spray area. The elevation of the ground increased as the airplane approached the designated field. Midway into the turn, the airplane impacted the ground and the fuselage was deformed. The pilot additionally reported that he did not experience any mechanical malfunction with the operation of the airplane.