THE PILOT STATED IN HIS WRITTEN REPORT THAT HE REFUELED THE AIRCRAFT PRIOR TO DEPARTURE WITH ABOUT 19 GALLONS OF AVIATION FUEL. ACCORDING TO THE PILOT, HE DEPARTED COLUMBIA AND CLIMBED TO ABOUT 10,000 FEET WHILE HE FLEW AROUND THE SIERRA NEVADA MOUNTAINS. AT ABOUT 1200 HOURS, HE TURNED AND HEADED BACK TO COLUMBIA. HE REPORTED THAT THE ENGINE BEGAN TO SURGE AND THE REAR CYLINDER EGT INDICATED A POTENTIAL FUEL STARVATION PROBLEM. THE ENGINE WAS NOT PRODUCING SUFFICIENT POWER TO MAINTAIN FLIGHT AND THE PILOT SET UP FOR A FORCED LANDING IN A MOUNTAIN MEADOW. HE STATED THAT THE ENGINE CONTINUED TO SURGE, EVEN AFTER THE THROTTLE WAS REDUCED TO IDLE, WHICH CAUSED THE AIRCRAFT TO OVER SHOOT HIS INTENDED LANDING SPOT. THE AIRCRAFT COLLIDED WITH TREES AT THE FAR END OF THE MEADOW. THE PILOT SAID THE AIRCRAFT IS NOT EQUIPPED WITH AN ELECTRIC BOOST PUMP. HE SPECULATED THAT THE ENGINE POWER PROBLEM WAS DUE TO EITHER VAPOR LOCK OR A MALFUNCTION OF THE ENGINE DRIVEN PUMP.