DURING A LEFT TURN AFTER TAKEOFF FROM A PRIVATE GRASS STRIP THE PILOT SAID HE ENCOUNTERED WIND SHEAR AND DID NOT HAVE SUFFICIENT ALTITUDE TO RECOVER. THE AIRCRAFT HIT THE TOPS OF TREES THEN FELL TO THE GROUND UPSIDE DOWN. THE PILOT AND HIS PASSENGER RECEIVED MINOR INJURIES BUT THE AIRCRAFT WAS DESTROYED BY THE POST CRASH FIRE.