According to the pilot, he did not visually confirm the quantity of fuel in the fuel tanks before departure. While about 3,500 ft above ground level the engine began to lose power. Subsequently, the engine lost all power, and the pilot turned back toward the departure airport. The pilot realized that the airplane would not be able to glide to the departure airport and attempted to land on a nearby grass runway. Unable to land on the grass runway due to obstacles, the pilot initiated a forced landing to a field. During the landing, the airplane struck a metal cattle gate, resulting in substantial damage to the left wing lift strut, horizontal stabilizer, and elevator. The pilot reported that there were no preaccident mechanical malfunctions or failures that would have precluded normal operation. During aircraft recovery, both left and right wing fuel tanks were found to be empty; no evidence of a breach in either fuel tank was noted.