THE ACFT MADE A FORCED LANDING AND COLLIDED WITH A PINE TREE AFTER A TAKEOFF WITH A TOW BAR ATTACHED TO THE NOSE GEAR. THE PILOT REPORTED THAT HE ATTACHED A TOW BAR TO GET THE ACFT LEVEL TO MEASURE THE OIL QUANTITY IN THE ENGINE. AFTER THEPREFLT INSPECTION HE TAXIED OUT AND DEPARTED. AT THIS ARPT ALL DEPARTURES ARE ON RWY 21 AND ALL LANDINGS ARE ON RWY 3. THE PILOT WAS FAMILIAR WITH THIS PROCEDURE. AFTER TAKEOFF THE PILOT WAS INFORMED BY RADIO THAT A TOW BAR WAS ATTACHED TOHIS NOSE GEAR AND WAS IN A TRAILING POSITION. FOLLOWING A FLYBY THE PILOT ATTEMPTED TO LAND ON RWY 21. ON FINAL APPROACHHE FEATHERED HIS FRONT ENGINE TO PRECLUDE DAMAGE DURING LANDING. HE WAS INFORMED BY RADIO HE WAS LANDING DOWNWIND. HE TRIED TO GO AROUND AND RESTART HIS ENGINE. WITH THE GEAR EXTENDED THE ACFT FAILED TO CLIMB. AS THE PILOT TRIED TO START THE ENGINE AND LINE UP ON RWY 3 HE WAS LOSING ALT AND AIRSPEED. ALMOST STALLING HE DECIDED TO LAND IN AN ADJACENT ROUGH FIELD. THE ACFT STOPPED AFTER IMPACTING A PINE TREE. DENSITY ALT WAS 7580 FT. THE ACFT WAS WITHIN 200 # OF GROSS WEIGHT.