According to the pilot, he was descending into the landing airport vicinity with the fuel selector on the right tank. The engine then lost power and he switched the fuel selector to the left tank, and then to the "both" position. The propeller continued to windmill and the pilot force-landed the airplane on an interstate. During the landing, the airplane touched down hard and the tailwheel separated from its mounting point and damaged the rudder. The pilot indicated that usually when the airplane is in a descent he positions the fuel selector on the "both" setting. He indicated that in a descent it is important that the selector is positioned to the both position to ensure adequate fuel flow. Additionally, the pilot reported that he may have encountered carburetor icing conditions and he did not immediately apply carburetor heat. According to the Federal Aviation Administration’s carburetor icing chart, icing conditions existed at glide and cruise power. Seven gallons of fuel were found in the airplane's fuel tanks. Following the accident, the engine was started and test run on the airframe using the remaining fuel in the airplane and no anomalies were noted.