When Lucas and Mark give John Jupiter a ride to Isabel Dent's place using the buckboard Jupiter is sitting on his trunk of possessions. After Jupiter and Dent go into the house Lucas and Mark leave with Jupiter's trunk. The groom is not going to live with the bride before marriage.
The post to which Jupiter is tied would have been a large wood timber, yet McCain picks it up briefly with one hand and then controls the movement with his other hand. This could not be possible, if the large post was the dense wood that would have been used for a hitching post.