THE PLT DID NOT RECHECK THE ACFT'S FUEL AT AN INTERMEDIATE STOP. AFTER HE DEPARTED & WAS IN CRUISE FLT, THE ENG LOST POWER. THE PLT RPRTD THAT THE FUEL GAGES INDCD THE TANKS WERE NEARLY HALF FULL AT THAT TIME. DURING A SUBSEQUENT FORCED LANDING, THE ACFT COLLIDED WITH TREES & WAS DAMAGED. A POST-ACDNT EXAM OF THE ACFT FUEL SYS REVEALED ABOUT 20 OUNCES FUEL IN THE RIGHT TANK. THE LEFT TANK WAS SPLIT OPEN, BUT THERE WAS NO EVIDENCE OF FUEL RESIDUE ON THE GROUND BELOW THE TANK. DURING AN OPNL CHECK OF THE ENG, IT STARTED & RAN NORMALLY