Cigar shaped vehicle hovering over farm field.

The story was told by my mother.  
Our dad was out in one of our fields doing fall plowing.  He was plowing this field and he got the feeling that he was being watched.  The tractor had its headlights on and he looked around, but did not observe anything at ground level.  He looked above the tractor as he reached the end of the field and observed a large cigar shaped vehicle hovering motionless above the tractor as he did his turn around.  This vehicle was observing and following him as he crossed the field.  He became paniced and decided to leave the field when he reached the other end of the field.
He raised the plow out of the ground and drove the tractor out of the field.  He then drove into a heavily grove of trees and when he reached it he shut off his headlights and shut off the tractor engine.  The cigar shaped vehicle followed him over the heavy wooded area and when the tractor was no longer visible the cigar shaped vehicle accelerated and streaked away at a great rate of speed.  
Dad then restarted the tractor and came back to the barn yard.  
Dad was physically shaken and we children were only told this story by our mother after our father's death.