On September 19, 2001, approximately 0920 central daylight time, an Ayres S2R-T11 agricultural airplane, N40173, was substantially damaged when it impacted a tree during a forced landing following a loss of engine power in cruise flight near Spur, Texas. The commercial pilot, sole occupant of the airplane, was not injured. The airplane was registered to and operated by Tri County Sprayers Inc., of Hamlin, Texas. Visual meteorological conditions prevailed, and a flight plan was not filed for the 14 Code of Federal Regulations Part 91 positioning flight. The flight departed the Hamlin Municipal Airport approximately 0900, and was destined for Crosbyton, Texas. The pilot reported that approximately 20 minutes into the flight, the engine started losing power. The pilot elected to execute a forced landing to a field. During the landing sequence, the airplane's right wing impacted a tree, the airplane spun around to the right, and the landing gear collapsed. According to an FAA inspector, who responded to the accident site, the right wing was substantially damaged, and there was fuel found in both fuel tanks. The operator reported that the engine was recovered and examined at a local maintenance facility. The maintenance mechanic stated that he performed a "Level 2 Propeller Strike Inspection" on the engine, in accordance with manufacturer's procedures. The inspection did not reveal any anomalies that would have prevented engine operation. The engine was then test run for approximately 3 hours at various power settings, and no anomalies were noted.