On April 8, 2000, at 1025 mountain daylight time, a Weatherly 201B, N1292W, nosed over during landing roll on a forced landing near Rocky Ford, Colorado. The commercial pilot received minor injuries and the aircraft sustained substantial damage. The flight was operating under Title 14 CFR Part 137 and no flight plan was filed. Visual meteorological conditions prevailed for this aerial application flight which departed Rocky Ford at 1008. According to the pilot, he was seeding a field and was flying at 80 to 100 feet above ground level (agl) with about 95 to 100 miles per hour (mph) indicated airspeed. He said the engine lost all power without any prior indication of the impending failure. In his statement, he said he attempted to check the magnetos, fuel selector, and turned the boost pump on without results. At approximately 30 feet agl, he abandoned trouble shooting and concentrated on the forced landing, which was to a plowed field. His statement said he touched down on the tail wheel at 45 to 50 mph. At about 30 mph the right main wheel dug in and the aircraft nosed over. Persons on the ground assisted the pilot from the aircraft. At the time of takeoff, the pilot estimated he had approximately 29 gallons of fuel on board the aircraft. The pilot said there was damage to the propeller and fuselage aft of the cockpit area. Examination of the engine provided evidence of a rocker arm failure. No reason for the failure could be determined.