On June 10, 1995, at 1615 central daylight time, an Ayres Corp S2R-T34, N3105E, was substantially damaged during a forced landing near DeValls Bluff, Arkansas. The commercial pilot was not injured. The aircraft was being operated by Vincent Aviation Inc., under Title 14 CFR Part 137. The flight originated from the Valley Airport, near DeValls Bluff, Arkansas, at 1610. Visual meteorological conditions prevailed for the local aerial application flight and a flight plan was not filed. The pilot stated, during an interview conducted by the investigator-in-charge, that the flight had just departed and was en route to a designated field for spraying. The airplane experienced a total loss of engine power and he executed a forced landing to a recently planted soybean field. The airplane landed and the tailwheel assembly separated from the airframe striking the rudder. The pilot reported that the airplane struck an "unknown object." On the Pilot/Operator Report, the pilot states that "small pieces of rubber [were] found in left main fuel tank, fuel line, and header tank." Sufficient material was found to block the fuel line to the engine, with subsequent total loss of engine power. The source of the rubber particles found in the fuel system is unknown.