he has a food plot on the property line...
It sounds to me like the guy is pissed because you are hunting too close to his food plot.
If the old man put the food plot on the property line, and Bull Byler is hunting next to it ON HIS OWN LAND, then that's just too bad for the old man. Just because someone puts in a food plot close to another persons property line doesn't mean that that persons neighbor should be denied hunting access to his own land just because it's close to the plot and he may harvest deer on his side that happen to frequent said plot. If the old man is so worried and upset about others hunting what he considers "his" deer just because he planted some clover, then he should have put the plot in the middle of his property, not next to someone else's property line. I don't even think that this is a matter of courtesy, since the guy basically wants to effectively deny him use of his own property.
Mike