ON INITIAL TAKEOFF, THE J-3 PILOT INITIATED A LEFT TURN AT ABOUT 125 FEET AGL. HE THEN NOTICED THAT THE AIRSPEED HAD DECAYED TO ABOUT 40 KNOTS. THE AIRPLANE STALLED, AND THE LEFT WING COLLIDED WITH THE GROUND BEFORE A RECOVERY COULD BE MADE. THE PILOT REPORTED NO MECHANICAL PROBLEMS WITH THE AIRPLANE; HE WAS MAINTAINING A STEEP, NOSE-HIGH ATTITUDE ON THE INITIAL CLIMB AND DID NOT MONITOR HIS AIRSPEED.