The pilot reported to the Federal Aviation Administration that he ran out of fuel while spraying crops and initiated a forced landing into a field. The pilot stated that he landed hard and the engine was separated from the airframe and subsequently broke in half. The airplane’s fuselage and wing were substantially damaged. Despite numerous attempts to contact the pilot, at the time this report was written, the pilot has not responded to the NTSB investigator-in-charge or submitted a completed NTSB pilot/operator 6120.1 form.